DC flashover performance of iced insulators under pressure and pollution conditions
名词解释
路透系统路透系统(Reuters)－－路透系统由路透通讯社创立，总部设在伦敦，路透社拥有的信息收集网络，联系－着全球５０００家银行和金融机构，２００多家交易所，２４小时不停地由总部发出各种经济信息和金融信息－，客户可以随时获得从外汇、债券到期货、股票、能源在内的各金融市场的实时行情。
路透系统的产品覆盖了－从信息到分析、交易、风险管理的整个金融运作过程。
雅各布天梯希腊神话中有这样一个故事：雅各布做梦沿着登天的梯子取得了“圣火”。
后人便把这梦想中的梯子，称之为雅各布天梯。
该展品由变压器、羊角电极等部分组成。
由变压器提供数十万伏的高压，在羊角电极间击穿空气，形成弓形电弧，产生磁场，使电弧向上运动，其运动过程类似于爬梯。
当电弧被拉长到600mm 左右，所施加的电压再不能维持产生电弧所需的条件，电弧就消失，此时羊角电极底部又会产生新的电弧，形成周而复始的电弧爬梯现象。
雅各布天梯则展示了电弧产生和消失的过程。
二根呈羊角形的管状电极，一极接高压电，另一个接地。
当电压升高到5万伏时，管状电极底部产生电弧，电弧逐级激荡而起，如一簇簇圣火似地向上爬升，犹如古希腊神话故事中的雅各布天梯。
在2－5万伏高压下，两电极最近处的空气首先被击穿，形成大量的正负等离子体，即产生电弧放电。
空气对流加上电动力的驱使，使电弧向上升，随着电弧被拉长，电弧通过的电阻加大，当电流送给电弧的能量小于由弧道向周围空气散出的热量时，电弧就会自行熄灭。
说明：在高压下，电极间距最小处的空气还会再次被击穿，发生第二次电弧放电，如此周而复始。
歌德斯堡七桥问题简介18世纪，东普鲁士的首府哥尼斯堡是一座景色迷人的城市，普莱格尔河横贯城区，使这座城市锦上添花，显得更加风光旖旋。
这条河有两条支流，在城中心汇成大河，在河的中央有一座美丽的小岛。
河上有七座各具特色的桥把岛和河岸连接起来。
起源每到傍晚，许多人都来此散步。
人们漫步于这七座桥之间，久而久之，就形成了这样一个问题：能不能既不重复又不遗漏地一次相继走遍这七座桥？这就是闻名遐迩的“哥尼斯堡七桥问题。
Agilent 6010A系列DC电源说明书
Basic DC Power Supplies essential features for a tight budgetMore detailed specifications at /find/601023Single-Output, Autoranging Programming resolution Voltage 50 mV 5 mV 15 mV 125 mV Current4.25 mA 30 mA 12.5 mA 1.25 mA DC floating voltage±550 V±240 V±240 V±550 Veither terminal can be grounded or floated from chassis ground AC input current100 Vac 24 A 24 A 24 A 24 A 120 Vac 24 A 24 A 24 A 24 A 220 Vac 15 A 15 A 15 A 15 A 240 Vac14 A 14 A 14 A 14 A WeightNet 16.3 kg (36 lb) 17.2 kg (38 lb) 16.3 kg (36 lb) 16.3 kg (36 lb)Shipping21.8 kg (48 lb)22.7 kg (50 lb)21.8 kg (48 lb)21.8 kg (48 lb)Autoranging Output:1981Remote Sensing:greater drops.Modulation:Input signal:Size:Warranty:0.5"More detailed specifications at /find/601024More detailed specifications at /find/603025Single-Output, Autoranging 200 W and 1000 W GPIB0.5"26Supplemental Characteristics for all model numbersRemote Sensing:Up to 2 V drop in each lead. Voltage regulation specification met with up to 0.5 V drop, but degrades for greater drops.Modulation: (analog programming of output voltage and current)Input signal:0 to 5 V or 0 to 4 k Ohms Software Driver:VXI Plug&Play Warranty: One yearSize:6030A–32A, 6035A:425.5 mm W x 132.6 mm H x 503.7 mm D (16.75 in x 5.25 in x 19.83 in).6033A, 6038A:212.3 mm W x 177.0 mm H x 516.4 mm D (8.36 in x 6.97 in x 17.87 in).More detailed specifications at /find/6030Supplemental Characteristics(Non-warranted characteristics determined by design and useful in applying the product)Programming resolution Voltage50 mV 5 mV 15 mV 5 mV 125 mV 1 5 mV Current4.25 mA 30 mA 12.5 mA 7.5 mA 1.25 mA 2.5 mA DC floating voltage±550 V±240 V±240 V±240 V±550 V±240 Veither terminal can be grounded or floated from chassis ground AC input current100 Vac 24 A 24 A 24 A 6 A 24 A 6 A 120 Vac 24 A 24 A 24 A 6.5 A 24 A 6.5 A 220 Vac 15 A 15 A 15 A 3.8 A 15 A 3.8 A 240 Vac14 A 14 A 14 A 3.6 A 14 A 3.6 A WeightNet 16.3 kg 17.2 kg 16.3 kg 9.6 kg 16.3 kg 9.6 kg (36 lb) (38 lb) (36 lb) (21 lb) (36 lb) (21 lb)Shipping21.8 kg 22.7 kg 21.8 kg 11.4 kg 21.8 kg 11.4 kg (48 lb)(50 lb)(48 lb)(25 lb)(48 lb)(25 lb)Agilent Models: 6030A, 6031A, 6032A, 6035A27Ordering InformationOpt 001 Front panel has only line switch, line indicator, and OVP adjust (6030A–33A and 6038A only)Opt 10087 to 106 Vac, 48 to 63 Hz(power supply output is derated to 75%)Opt 120 104 to 127 Vac, 47 to 63 Hz Opt 220191 to 233 Vac, 48 to 63 Hz Opt 240209 to 250 Vac, 48 to 63 Hz Opt 800Rack-mount Kit for Two Half-rack Units Side by Side. Lock link Kit p/n 5061-9694 and 7 in Rack adapter Kit 5063-9215*Opt 908Rack-mount Kit for a Single Half-rack Unit 6033A and 6038A(with blank filler panel); p/n 5062-3960, 6030A–32A and 6035A; p/n 5062-3977*Opt 909 Rack-mount Kit with Handles.For 6030A–32A, 6035A; p/n 5062-3983More detailed specifications at /find/6030Opt 0L1Full documentation on CD-ROM, and printed standard documentation packageOpt 0L2Extra copy of standard printed documentation package Opt 0B3 Service ManualOpt 0B0 Full documentation on CD-ROM onlyOpt J01 Stabilization for loads up to 10 Henries (not available on 6033A)A line cord option must be specified,see the AC line voltage and cord section.*Support rails requiredTerminal Strip DetailScrew Size M3.5 x 0.6VM IM VP IP B6B1Agilent Models: 6033A, 6038AAccessories5080-2148Serial Link Cable,2 m (6.6 ft)1494-0060Rack Slide Kit E3663AC Support rails for Agilent rack cabinetsYour Requested Excerpt from theAgilent System and Bench Instruments Catalog 2006The preceding page(s) are an excerpt from the 2006 Systemand Bench Instruments Catalog. We hope that these pages supply the information that you currently need. If you would like to have further information about the extensive selection of Agilent DC power supplies, please visit /find/power to print a copy of the complete catalog, or to request that a copy be sent to you. You will also find a lot of other useful information on this Web site.In the full System and Bench Instruments Catalog, you willfind that Agilent offers much more than DC power supplies. This catalog contains detailed technical and application information on digital multimeters, DC power supplies, arbitrary waveform generators, and many more instruments. If you need basic, clean, power for your lab bench, it’s there. In each power product category we have also integrated the capabilities you need fora complete power solution, including extensive measurement and analysis capabilities.Please give us a call at your local Agilent Technologies sales office, or call a regional office listed, for assistance in choosing or using Agilent power products.Keep up to date with Agilent’s Test and Measurement Email UpdatesAs an Email Update subscriber, you will receive periodic customized email updates that match the areas of interestthat you have specified. Your update will include productsand services, applications and support information, events and promotions. Sign up today at /find/emailupdates. Check off DC power supplies, AC power sources or electronic loads on your registration form, and we will promptly let you know what’s new in power products. Our Privacy Statement at /go/privacy describes our commitment to you regarding your For more information on Agilent Technologies’ products, applicationsor services, please contact your local Agilent office. The complete list is available at:/find/contactusPhone or FaxUnited States:(tel) 800 829 4444(fax) 800 829 4433Canada:(tel) 877 894 4414(fax) 800 746 4866China:(tel) 800 810 0189(fax) 800 820 2816Europe:(tel) 31 20 547 2111Japan:(tel) (81) 426 56 7832(fax) (81) 426 56 7840Korea:(tel) (080) 769 0800(fax) (080) 769 0900Latin America:(tel) (305) 269 7500Taiwan:(tel) 0800 047 866(fax) 0800 286 331Other Asia Pacific Countries:(tel) (65) 6375 8100(fax) (65) 6755 0042Email:*****************Contacts revised: 09/26/05Product specifications and descriptions in this document subject to change without notice.© Agilent Technologies, Inc. 2006 Printed in the USA, February 8, 2006Agilent Technologies。
杰弗里高效DC逆变技术壁挂型空调热泵系统说明书
G10 Yes Yes High Efficiency Rotary R410A Yes Yes Acrylic-Resin/Anti-Corrosive Yes Yes Yes Yes Yes Yes Yes Yes Crossflow 4 Speeds Yes No No
Yes Yes Yes Yes Yes Yes Yes Yes No Yes Yes No Yes Yes Yes Yes Yes Yes Yes
• Wi-Fi Included • Low Ambient Cooling down to -4°F (Range -4°F to 115°F) • Low Ambient Heating down to -13°F (Range -13°F to 75°F) • Coil (Indoor and Outdoor) Copper Tube / Aluminum Fin • Blue Colored Fin - 500 Hrs Salt Spray Tested
Space to the wall at least 6 inch
Space to the obstruction at least 24 inch
Space to the obstruction at least 6 inch
Specifications are subject to change without notice. Manufacturer reserves the right to discontinue or modify specificaitons or designs without notice or without incurring obligations. All Rights reserved.
电磁式电压互感器铁芯饱和引起的铁磁谐振现象
电磁式电压互感器铁芯饱和引起的铁磁谐振现象发表时间：2012-12-21T15:34:45.170Z 来源：《建筑学研究前沿》2012年9月Under供稿作者：杨晔[导读] 显然，三次谐波谐振也使电压互感器两端出现较高的过电压。
杨晔（无锡市恒驰电力发展有限公司 214161）摘要：运行经验证明，在我国中性点绝缘、中性点经消弧线图接地以及中性点直接接地的3～220kV电网中，都曾发生过由于电磁式电压互感器铁芯饱和引起的铁磁谐振过电压。
例如，江苏某220kV变电所因中性点临时不接地曾引起互感器的谐振过电压；东北电网某154kV经消弧线图接地系统，曾因消弧线圈；临时脱离运行引起互感器的谐振过电压；其中以在中性点绝缘的配电网中出现的较为频繁，是造成事故最多的一种内部过电压，因为其他接地系统只有当它们变成中性点绝缘系统时才有可能发生这种过电压。
关键词：过电压；物理概念；铁磁谐振现象Electromagnetic voltage transformer core saturation caused by ferromagnetic resonance phenomenon YangYe(wuxi constant chi electric power development co., LTD. 214161) Pick to: operating experience proved, in our country neutral insulation, neutral by petersen diagram ground and neutral directly grounded 3 ~ 220 kv power grid, have happened because of electromagnetic voltage transformer core saturation caused by ferromagnetic resonance overvoltage. For example, jiangsu a 220 kv substation for neutral temporary not earth once caused a transformer of resonance overvoltage; Northeast power grid a 154 kv via petersen diagram grounding system, once for arc suppression coil; Temporary from operation cause transformer of resonance overvoltage; Among them with the distribution network in neutral insulation appeared in more frequent, causing accidents is a kind of most internal overvoltage, because other grounding system only when they become neutral insulation system may not happen until the overvoltage. Keywords: overvoltage; Physical concepts; Ferromagnetic resonance phenomenon一、过电压产生的基本物理概念电磁式电压互感器引起的铁磁谐振过电压，从本质上讲，是由于电磁式电压互感器的非线性电感与系统的对地电容构成的铁磁谐振所引起的。
《光学快报》：新技术为液冷计算机研发扫清障
美 国 普 尔 曼 市 华 盛 顿 州 立 大 学 的材 料 物 理 学 家Ｊ．ＴｈＯｍ ｓ ａ Ｄｃ ｉｓ ｎ ｉｋｎ ｏ 对此表示赞同 ，认 为经由微 通道流动 的液体 “ 对于 大量的微 流体 应用确 实很 重要 ”。他 说 ，难题 在于要筛选 出这项技术 中的许 多 变量 ，例 如形状 、深度 以及 通道 的数量 、液滴 的大小 。Ｄｉｋｎ ｏ 表 ｃ ｉｓ ｎ 示 “ 很显然，这意味着还有一 些非 常有趣 的实验 。”
存在 。 Ｇｕ ＃ 充 说 ，他 ￣ Ｖ ｒｂ ｅ 还 用 丙 酮 和 甲醇 进 行 了 实 验 ，并 取 得 ｏｈ ］ １ｏｏ ｙｖ 了类似的结 果。他说 ，这很棒 ，因为这项技 术很可能用在一 些闭环系
为超 级 毛 细 的 新技 术最终将
帮助科学 家开发 出液 冷计算机 。专家表示 ，这种方法 能够 为冷却计 算 机硬件提供 一种更佳 的方式 ，同时为新一代 高能微处理器 的使用扫清
而这项技 术就是从 早 巳在 医学领域 中占有一席 的计
我 国首 台Ｊ 万亿次翘叙 计并机年 内将抉 国遗 １ ．
算机断层 摄像技术（ ｏ ｕｅ ｏ ｇａ ｈ Ｃ ｍｐ ｔｄ Ｔ ｍｏ ｐ ｙ，简称Ｃ ） ｒ Ｔ发 展而来。
２ ０ 年 ，一 台６ 层螺旋 （ 一 ｌ ｅＣ 首次在渥太华 ０６ ４ ６ Ｓｉ ） Ｔ ４ ｃ 这是 “ 天河一号 ”千万亿次超级计算机 系统 。 大学 心脏研 究所 内启用 ，这亦 是加拿 大将该机器 应用到 新华 网天津 ４月 ７日电 （ 记者 罗捷 ）记者从 天津市科委 了解到 ，我 国首台千万亿 万例临床应用 为 次超级计算机 “ 天河一号 ” ，预计 今年下 半年安装 由我 国 自行设计制造 的 “ 飞腾 ”计 心脏病研 究中 的首例 。几年来 ，超过２４ 该研 究中心 的技术 员提供 大量 可靠数据 ，最终助 他们发 算机 中央处理器 （ ） 片。届 时 ，其运算速度和效率将 大幅提升 。 Ｃ ＰＵ 芯
热红外传感史
History of infrared detectorsA.ROGALSKI*Institute of Applied Physics, Military University of Technology, 2 Kaliskiego Str.,00–908 Warsaw, PolandThis paper overviews the history of infrared detector materials starting with Herschel’s experiment with thermometer on February11th,1800.Infrared detectors are in general used to detect,image,and measure patterns of the thermal heat radia−tion which all objects emit.At the beginning,their development was connected with thermal detectors,such as ther−mocouples and bolometers,which are still used today and which are generally sensitive to all infrared wavelengths and op−erate at room temperature.The second kind of detectors,called the photon detectors,was mainly developed during the20th Century to improve sensitivity and response time.These detectors have been extensively developed since the1940’s.Lead sulphide(PbS)was the first practical IR detector with sensitivity to infrared wavelengths up to~3μm.After World War II infrared detector technology development was and continues to be primarily driven by military applications.Discovery of variable band gap HgCdTe ternary alloy by Lawson and co−workers in1959opened a new area in IR detector technology and has provided an unprecedented degree of freedom in infrared detector design.Many of these advances were transferred to IR astronomy from Departments of Defence ter on civilian applications of infrared technology are frequently called“dual−use technology applications.”One should point out the growing utilisation of IR technologies in the civilian sphere based on the use of new materials and technologies,as well as the noticeable price decrease in these high cost tech−nologies.In the last four decades different types of detectors are combined with electronic readouts to make detector focal plane arrays(FPAs).Development in FPA technology has revolutionized infrared imaging.Progress in integrated circuit design and fabrication techniques has resulted in continued rapid growth in the size and performance of these solid state arrays.Keywords:thermal and photon detectors, lead salt detectors, HgCdTe detectors, microbolometers, focal plane arrays.Contents1.Introduction2.Historical perspective3.Classification of infrared detectors3.1.Photon detectors3.2.Thermal detectors4.Post−War activity5.HgCdTe era6.Alternative material systems6.1.InSb and InGaAs6.2.GaAs/AlGaAs quantum well superlattices6.3.InAs/GaInSb strained layer superlattices6.4.Hg−based alternatives to HgCdTe7.New revolution in thermal detectors8.Focal plane arrays – revolution in imaging systems8.1.Cooled FPAs8.2.Uncooled FPAs8.3.Readiness level of LWIR detector technologies9.SummaryReferences 1.IntroductionLooking back over the past1000years we notice that infra−red radiation(IR)itself was unknown until212years ago when Herschel’s experiment with thermometer and prism was first reported.Frederick William Herschel(1738–1822) was born in Hanover,Germany but emigrated to Britain at age19,where he became well known as both a musician and an astronomer.Herschel became most famous for the discovery of Uranus in1781(the first new planet found since antiquity)in addition to two of its major moons,Tita−nia and Oberon.He also discovered two moons of Saturn and infrared radiation.Herschel is also known for the twenty−four symphonies that he composed.W.Herschel made another milestone discovery–discov−ery of infrared light on February11th,1800.He studied the spectrum of sunlight with a prism[see Fig.1in Ref.1],mea−suring temperature of each colour.The detector consisted of liquid in a glass thermometer with a specially blackened bulb to absorb radiation.Herschel built a crude monochromator that used a thermometer as a detector,so that he could mea−sure the distribution of energy in sunlight and found that the highest temperature was just beyond the red,what we now call the infrared(‘below the red’,from the Latin‘infra’–be−OPTO−ELECTRONICS REVIEW20(3),279–308DOI: 10.2478/s11772−012−0037−7*e−mail: rogan@.pllow)–see Fig.1(b)[2].In April 1800he reported it to the Royal Society as dark heat (Ref.1,pp.288–290):Here the thermometer No.1rose 7degrees,in 10minu−tes,by an exposure to the full red coloured rays.I drew back the stand,till the centre of the ball of No.1was just at the vanishing of the red colour,so that half its ball was within,and half without,the visible rays of theAnd here the thermometerin 16minutes,degrees,when its centre was inch out of the raysof the sun.as had a rising of 9de−grees,and here the difference is almost too trifling to suppose,that latter situation of the thermometer was much beyond the maximum of the heating power;while,at the same time,the experiment sufficiently indi−cates,that the place inquired after need not be looked for at a greater distance.Making further experiments on what Herschel called the ‘calorific rays’that existed beyond the red part of the spec−trum,he found that they were reflected,refracted,absorbed and transmitted just like visible light [1,3,4].The early history of IR was reviewed about 50years ago in three well−known monographs [5–7].Many historical information can be also found in four papers published by Barr [3,4,8,9]and in more recently published monograph [10].Table 1summarises the historical development of infrared physics and technology [11,12].2.Historical perspectiveFor thirty years following Herschel’s discovery,very little progress was made beyond establishing that the infrared ra−diation obeyed the simplest laws of optics.Slow progress inthe study of infrared was caused by the lack of sensitive and accurate detectors –the experimenters were handicapped by the ordinary thermometer.However,towards the second de−cade of the 19th century,Thomas Johann Seebeck began to examine the junction behaviour of electrically conductive materials.In 1821he discovered that a small electric current will flow in a closed circuit of two dissimilar metallic con−ductors,when their junctions are kept at different tempera−tures [13].During that time,most physicists thought that ra−diant heat and light were different phenomena,and the dis−covery of Seebeck indirectly contributed to a revival of the debate on the nature of heat.Due to small output vol−tage of Seebeck’s junctions,some μV/K,the measurement of very small temperature differences were prevented.In 1829L.Nobili made the first thermocouple and improved electrical thermometer based on the thermoelectric effect discovered by Seebeck in 1826.Four years later,M.Melloni introduced the idea of connecting several bismuth−copper thermocouples in series,generating a higher and,therefore,measurable output voltage.It was at least 40times more sensitive than the best thermometer available and could de−tect the heat from a person at a distance of 30ft [8].The out−put voltage of such a thermopile structure linearly increases with the number of connected thermocouples.An example of thermopile’s prototype invented by Nobili is shown in Fig.2(a).It consists of twelve large bismuth and antimony elements.The elements were placed upright in a brass ring secured to an adjustable support,and were screened by a wooden disk with a 15−mm central aperture.Incomplete version of the Nobili−Melloni thermopile originally fitted with the brass cone−shaped tubes to collect ra−diant heat is shown in Fig.2(b).This instrument was much more sensi−tive than the thermometers previously used and became the most widely used detector of IR radiation for the next half century.The third member of the trio,Langley’s bolometer appea−red in 1880[7].Samuel Pierpont Langley (1834–1906)used two thin ribbons of platinum foil connected so as to form two arms of a Wheatstone bridge (see Fig.3)[15].This instrument enabled him to study solar irradiance far into its infrared region and to measure theintensityof solar radia−tion at various wavelengths [9,16,17].The bolometer’s sen−History of infrared detectorsFig.1.Herschel’s first experiment:A,B –the small stand,1,2,3–the thermometers upon it,C,D –the prism at the window,E –the spec−trum thrown upon the table,so as to bring the last quarter of an inch of the read colour upon the stand (after Ref.1).InsideSir FrederickWilliam Herschel (1738–1822)measures infrared light from the sun– artist’s impression (after Ref. 2).Fig.2.The Nobili−Meloni thermopiles:(a)thermopile’s prototype invented by Nobili (ca.1829),(b)incomplete version of the Nobili−−Melloni thermopile (ca.1831).Museo Galileo –Institute and Museum of the History of Science,Piazza dei Giudici 1,50122Florence, Italy (after Ref. 14).Table 1. Milestones in the development of infrared physics and technology (up−dated after Refs. 11 and 12)Year Event1800Discovery of the existence of thermal radiation in the invisible beyond the red by W. HERSCHEL1821Discovery of the thermoelectric effects using an antimony−copper pair by T.J. SEEBECK1830Thermal element for thermal radiation measurement by L. NOBILI1833Thermopile consisting of 10 in−line Sb−Bi thermal pairs by L. NOBILI and M. MELLONI1834Discovery of the PELTIER effect on a current−fed pair of two different conductors by J.C. PELTIER1835Formulation of the hypothesis that light and electromagnetic radiation are of the same nature by A.M. AMPERE1839Solar absorption spectrum of the atmosphere and the role of water vapour by M. MELLONI1840Discovery of the three atmospheric windows by J. HERSCHEL (son of W. HERSCHEL)1857Harmonization of the three thermoelectric effects (SEEBECK, PELTIER, THOMSON) by W. THOMSON (Lord KELVIN)1859Relationship between absorption and emission by G. KIRCHHOFF1864Theory of electromagnetic radiation by J.C. MAXWELL1873Discovery of photoconductive effect in selenium by W. SMITH1876Discovery of photovoltaic effect in selenium (photopiles) by W.G. ADAMS and A.E. DAY1879Empirical relationship between radiation intensity and temperature of a blackbody by J. STEFAN1880Study of absorption characteristics of the atmosphere through a Pt bolometer resistance by S.P. LANGLEY1883Study of transmission characteristics of IR−transparent materials by M. MELLONI1884Thermodynamic derivation of the STEFAN law by L. BOLTZMANN1887Observation of photoelectric effect in the ultraviolet by H. HERTZ1890J. ELSTER and H. GEITEL constructed a photoemissive detector consisted of an alkali−metal cathode1894, 1900Derivation of the wavelength relation of blackbody radiation by J.W. RAYEIGH and W. WIEN1900Discovery of quantum properties of light by M. PLANCK1903Temperature measurements of stars and planets using IR radiometry and spectrometry by W.W. COBLENTZ1905 A. EINSTEIN established the theory of photoelectricity1911R. ROSLING made the first television image tube on the principle of cathode ray tubes constructed by F. Braun in 18971914Application of bolometers for the remote exploration of people and aircrafts ( a man at 200 m and a plane at 1000 m)1917T.W. CASE developed the first infrared photoconductor from substance composed of thallium and sulphur1923W. SCHOTTKY established the theory of dry rectifiers1925V.K. ZWORYKIN made a television image tube (kinescope) then between 1925 and 1933, the first electronic camera with the aid of converter tube (iconoscope)1928Proposal of the idea of the electro−optical converter (including the multistage one) by G. HOLST, J.H. DE BOER, M.C. TEVES, and C.F. VEENEMANS1929L.R. KOHLER made a converter tube with a photocathode (Ag/O/Cs) sensitive in the near infrared1930IR direction finders based on PbS quantum detectors in the wavelength range 1.5–3.0 μm for military applications (GUDDEN, GÖRLICH and KUTSCHER), increased range in World War II to 30 km for ships and 7 km for tanks (3–5 μm)1934First IR image converter1939Development of the first IR display unit in the United States (Sniperscope, Snooperscope)1941R.S. OHL observed the photovoltaic effect shown by a p−n junction in a silicon1942G. EASTMAN (Kodak) offered the first film sensitive to the infrared1947Pneumatically acting, high−detectivity radiation detector by M.J.E. GOLAY1954First imaging cameras based on thermopiles (exposure time of 20 min per image) and on bolometers (4 min)1955Mass production start of IR seeker heads for IR guided rockets in the US (PbS and PbTe detectors, later InSb detectors for Sidewinder rockets)1957Discovery of HgCdTe ternary alloy as infrared detector material by W.D. LAWSON, S. NELSON, and A.S. YOUNG1961Discovery of extrinsic Ge:Hg and its application (linear array) in the first LWIR FLIR systems1965Mass production start of IR cameras for civil applications in Sweden (single−element sensors with optomechanical scanner: AGA Thermografiesystem 660)1970Discovery of charge−couple device (CCD) by W.S. BOYLE and G.E. SMITH1970Production start of IR sensor arrays (monolithic Si−arrays: R.A. SOREF 1968; IR−CCD: 1970; SCHOTTKY diode arrays: F.D.SHEPHERD and A.C. YANG 1973; IR−CMOS: 1980; SPRITE: T. ELIOTT 1981)1975Lunch of national programmes for making spatially high resolution observation systems in the infrared from multielement detectors integrated in a mini cooler (so−called first generation systems): common module (CM) in the United States, thermal imaging commonmodule (TICM) in Great Britain, syteme modulaire termique (SMT) in France1975First In bump hybrid infrared focal plane array1977Discovery of the broken−gap type−II InAs/GaSb superlattices by G.A. SAI−HALASZ, R. TSU, and L. ESAKI1980Development and production of second generation systems [cameras fitted with hybrid HgCdTe(InSb)/Si(readout) FPAs].First demonstration of two−colour back−to−back SWIR GaInAsP detector by J.C. CAMPBELL, A.G. DENTAI, T.P. LEE,and C.A. BURRUS1985Development and mass production of cameras fitted with Schottky diode FPAs (platinum silicide)1990Development and production of quantum well infrared photoconductor (QWIP) hybrid second generation systems1995Production start of IR cameras with uncooled FPAs (focal plane arrays; microbolometer−based and pyroelectric)2000Development and production of third generation infrared systemssitivity was much greater than that of contemporary thermo−piles which were little improved since their use by Melloni. Langley continued to develop his bolometer for the next20 years(400times more sensitive than his first efforts).His latest bolometer could detect the heat from a cow at a dis−tance of quarter of mile [9].From the above information results that at the beginning the development of the IR detectors was connected with ther−mal detectors.The first photon effect,photoconductive ef−fect,was discovered by Smith in1873when he experimented with selenium as an insulator for submarine cables[18].This discovery provided a fertile field of investigation for several decades,though most of the efforts were of doubtful quality. By1927,over1500articles and100patents were listed on photosensitive selenium[19].It should be mentioned that the literature of the early1900’s shows increasing interest in the application of infrared as solution to numerous problems[7].A special contribution of William Coblenz(1873–1962)to infrared radiometry and spectroscopy is marked by huge bib−liography containing hundreds of scientific publications, talks,and abstracts to his credit[20,21].In1915,W.Cob−lentz at the US National Bureau of Standards develops ther−mopile detectors,which he uses to measure the infrared radi−ation from110stars.However,the low sensitivity of early in−frared instruments prevented the detection of other near−IR sources.Work in infrared astronomy remained at a low level until breakthroughs in the development of new,sensitive infrared detectors were achieved in the late1950’s.The principle of photoemission was first demonstrated in1887when Hertz discovered that negatively charged par−ticles were emitted from a conductor if it was irradiated with ultraviolet[22].Further studies revealed that this effect could be produced with visible radiation using an alkali metal electrode [23].Rectifying properties of semiconductor−metal contact were discovered by Ferdinand Braun in1874[24],when he probed a naturally−occurring lead sulphide(galena)crystal with the point of a thin metal wire and noted that current flowed freely in one direction only.Next,Jagadis Chandra Bose demonstrated the use of galena−metal point contact to detect millimetre electromagnetic waves.In1901he filed a U.S patent for a point−contact semiconductor rectifier for detecting radio signals[25].This type of contact called cat’s whisker detector(sometimes also as crystal detector)played serious role in the initial phase of radio development.How−ever,this contact was not used in a radiation detector for the next several decades.Although crystal rectifiers allowed to fabricate simple radio sets,however,by the mid−1920s the predictable performance of vacuum−tubes replaced them in most radio applications.The period between World Wars I and II is marked by the development of photon detectors and image converters and by emergence of infrared spectroscopy as one of the key analytical techniques available to chemists.The image con−verter,developed on the eve of World War II,was of tre−mendous interest to the military because it enabled man to see in the dark.The first IR photoconductor was developed by Theodore W.Case in1917[26].He discovered that a substance com−posed of thallium and sulphur(Tl2S)exhibited photocon−ductivity.Supported by the US Army between1917and 1918,Case adapted these relatively unreliable detectors for use as sensors in an infrared signalling device[27].The pro−totype signalling system,consisting of a60−inch diameter searchlight as the source of radiation and a thallous sulphide detector at the focus of a24−inch diameter paraboloid mir−ror,sent messages18miles through what was described as ‘smoky atmosphere’in1917.However,instability of resis−tance in the presence of light or polarizing voltage,loss of responsivity due to over−exposure to light,high noise,slug−gish response and lack of reproducibility seemed to be inhe−rent weaknesses.Work was discontinued in1918;commu−nication by the detection of infrared radiation appeared dis−tinctly ter Case found that the addition of oxygen greatly enhanced the response [28].The idea of the electro−optical converter,including the multistage one,was proposed by Holst et al.in1928[29]. The first attempt to make the converter was not successful.A working tube consisted of a photocathode in close proxi−mity to a fluorescent screen was made by the authors in 1934 in Philips firm.In about1930,the appearance of the Cs−O−Ag photo−tube,with stable characteristics,to great extent discouraged further development of photoconductive cells until about 1940.The Cs−O−Ag photocathode(also called S−1)elabo−History of infrared detectorsFig.3.Longley’s bolometer(a)composed of two sets of thin plati−num strips(b),a Wheatstone bridge,a battery,and a galvanometer measuring electrical current (after Ref. 15 and 16).rated by Koller and Campbell[30]had a quantum efficiency two orders of magnitude above anything previously studied, and consequently a new era in photoemissive devices was inaugurated[31].In the same year,the Japanese scientists S. Asao and M.Suzuki reported a method for enhancing the sensitivity of silver in the S−1photocathode[32].Consisted of a layer of caesium on oxidized silver,S−1is sensitive with useful response in the near infrared,out to approxi−mately1.2μm,and the visible and ultraviolet region,down to0.3μm.Probably the most significant IR development in the United States during1930’s was the Radio Corporation of America(RCA)IR image tube.During World War II, near−IR(NIR)cathodes were coupled to visible phosphors to provide a NIR image converter.With the establishment of the National Defence Research Committee,the develop−ment of this tube was accelerated.In1942,the tube went into production as the RCA1P25image converter(see Fig.4).This was one of the tubes used during World War II as a part of the”Snooperscope”and”Sniperscope,”which were used for night observation with infrared sources of illumination.Since then various photocathodes have been developed including bialkali photocathodes for the visible region,multialkali photocathodes with high sensitivity ex−tending to the infrared region and alkali halide photocatho−des intended for ultraviolet detection.The early concepts of image intensification were not basically different from those today.However,the early devices suffered from two major deficiencies:poor photo−cathodes and poor ter development of both cathode and coupling technologies changed the image in−tensifier into much more useful device.The concept of image intensification by cascading stages was suggested independently by number of workers.In Great Britain,the work was directed toward proximity focused tubes,while in the United State and in Germany–to electrostatically focused tubes.A history of night vision imaging devices is given by Biberman and Sendall in monograph Electro−Opti−cal Imaging:System Performance and Modelling,SPIE Press,2000[10].The Biberman’s monograph describes the basic trends of infrared optoelectronics development in the USA,Great Britain,France,and Germany.Seven years later Ponomarenko and Filachev completed this monograph writ−ing the book Infrared Techniques and Electro−Optics in Russia:A History1946−2006,SPIE Press,about achieve−ments of IR techniques and electrooptics in the former USSR and Russia [33].In the early1930’s,interest in improved detectors began in Germany[27,34,35].In1933,Edgar W.Kutzscher at the University of Berlin,discovered that lead sulphide(from natural galena found in Sardinia)was photoconductive and had response to about3μm.B.Gudden at the University of Prague used evaporation techniques to develop sensitive PbS films.Work directed by Kutzscher,initially at the Uni−versity of Berlin and later at the Electroacustic Company in Kiel,dealt primarily with the chemical deposition approach to film formation.This work ultimately lead to the fabrica−tion of the most sensitive German detectors.These works were,of course,done under great secrecy and the results were not generally known until after1945.Lead sulphide photoconductors were brought to the manufacturing stage of development in Germany in about1943.Lead sulphide was the first practical infrared detector deployed in a variety of applications during the war.The most notable was the Kiel IV,an airborne IR system that had excellent range and which was produced at Carl Zeiss in Jena under the direction of Werner K. Weihe [6].In1941,Robert J.Cashman improved the technology of thallous sulphide detectors,which led to successful produc−tion[36,37].Cashman,after success with thallous sulphide detectors,concentrated his efforts on lead sulphide detec−tors,which were first produced in the United States at Northwestern University in1944.After World War II Cash−man found that other semiconductors of the lead salt family (PbSe and PbTe)showed promise as infrared detectors[38]. The early detector cells manufactured by Cashman are shown in Fig. 5.Fig.4.The original1P25image converter tube developed by the RCA(a).This device measures115×38mm overall and has7pins.It opera−tion is indicated by the schematic drawing (b).After1945,the wide−ranging German trajectory of research was essentially the direction continued in the USA, Great Britain and Soviet Union under military sponsorship after the war[27,39].Kutzscher’s facilities were captured by the Russians,thus providing the basis for early Soviet detector development.From1946,detector technology was rapidly disseminated to firms such as Mullard Ltd.in Southampton,UK,as part of war reparations,and some−times was accompanied by the valuable tacit knowledge of technical experts.E.W.Kutzscher,for example,was flown to Britain from Kiel after the war,and subsequently had an important influence on American developments when he joined Lockheed Aircraft Co.in Burbank,California as a research scientist.Although the fabrication methods developed for lead salt photoconductors was usually not completely under−stood,their properties are well established and reproducibi−lity could only be achieved after following well−tried reci−pes.Unlike most other semiconductor IR detectors,lead salt photoconductive materials are used in the form of polycrys−talline films approximately1μm thick and with individual crystallites ranging in size from approximately0.1–1.0μm. They are usually prepared by chemical deposition using empirical recipes,which generally yields better uniformity of response and more stable results than the evaporative methods.In order to obtain high−performance detectors, lead chalcogenide films need to be sensitized by oxidation. The oxidation may be carried out by using additives in the deposition bath,by post−deposition heat treatment in the presence of oxygen,or by chemical oxidation of the film. The effect of the oxidant is to introduce sensitizing centres and additional states into the bandgap and thereby increase the lifetime of the photoexcited holes in the p−type material.3.Classification of infrared detectorsObserving a history of the development of the IR detector technology after World War II,many materials have been investigated.A simple theorem,after Norton[40],can be stated:”All physical phenomena in the range of about0.1–1 eV will be proposed for IR detectors”.Among these effects are:thermoelectric power(thermocouples),change in elec−trical conductivity(bolometers),gas expansion(Golay cell), pyroelectricity(pyroelectric detectors),photon drag,Jose−phson effect(Josephson junctions,SQUIDs),internal emis−sion(PtSi Schottky barriers),fundamental absorption(in−trinsic photodetectors),impurity absorption(extrinsic pho−todetectors),low dimensional solids[superlattice(SL), quantum well(QW)and quantum dot(QD)detectors], different type of phase transitions, etc.Figure6gives approximate dates of significant develop−ment efforts for the materials mentioned.The years during World War II saw the origins of modern IR detector tech−nology.Recent success in applying infrared technology to remote sensing problems has been made possible by the successful development of high−performance infrared de−tectors over the last six decades.Photon IR technology com−bined with semiconductor material science,photolithogra−phy technology developed for integrated circuits,and the impetus of Cold War military preparedness have propelled extraordinary advances in IR capabilities within a short time period during the last century [41].The majority of optical detectors can be classified in two broad categories:photon detectors(also called quantum detectors) and thermal detectors.3.1.Photon detectorsIn photon detectors the radiation is absorbed within the material by interaction with electrons either bound to lattice atoms or to impurity atoms or with free electrons.The observed electrical output signal results from the changed electronic energy distribution.The photon detectors show a selective wavelength dependence of response per unit incident radiation power(see Fig.8).They exhibit both a good signal−to−noise performance and a very fast res−ponse.But to achieve this,the photon IR detectors require cryogenic cooling.This is necessary to prevent the thermalHistory of infrared detectorsFig.5.Cashman’s detector cells:(a)Tl2S cell(ca.1943):a grid of two intermeshing comb−line sets of conducting paths were first pro−vided and next the T2S was evaporated over the grid structure;(b) PbS cell(ca.1945)the PbS layer was evaporated on the wall of the tube on which electrical leads had been drawn with aquadag(afterRef. 38).。
乱花渐欲迷人眼 2007秋季DC新品特辑
乱花渐欲迷人眼 2007秋季DC新品特辑
佚名
【期刊名称】《数码》
【年(卷),期】2007(000)010
【摘要】2007年秋，注定是个DSLR混战，影友狂欢的时刻，除了老牌影像厂商佳能、尼康隆重推出各自的中、高端数码单反新品，博得影友无数眼球外，刚刚进入DSLR市场1年有余的新兴势力索尼也不遗余力，携中端数码单反产品α700
汹涌而来。
便携型消费级数码相机方面，索尼、佳能、尼康、奥林巴斯、柯达等DC厂商也都积极展开了新一轮的产品升级攻势。
一时之间，竟恍如身入百花丛中，颇有乱花渐欲这人眼之感。
如此这般，就让小编为大家理理脉络，看看究竟有哪些产品问世，哪些精品值得我们关注吧！
【总页数】6页(P98-103)
【正文语种】中文
【中图分类】TB852.1
【相关文献】
1.testo 327全新锅炉燃烧效率分析仪亮相德图2007年秋季新品发布 [J],
2.乱花渐欲迷人眼——Broadcast Asia 2007展会报道 [J], 马海龙
3.新加坡，HP，以娱乐的方式——2007HP全球战略暨秋季新品发布会 [J],
4.2007通信展新品特辑 [J],
5.为人生添彩，助商务腾飞——2007年佳能（中国）秋季打印机新品发布会在京召开 [J],
因版权原因，仅展示原文概要，查看原文内容请购买。
电源也玩半导体散热多彩ICE CUBE-550极冻电源
电源也玩半导体散热多彩ICE CUBE-550极冻电源
佚名
【期刊名称】《《微型计算机》》
【年(卷),期】2006(000)024
【摘要】最近多彩新推出了一款极冻电源，定位于多彩精品系列．额定功率达到了550W，双路＋12V输出可以分别达到17A．并具备过压、欠压、过功率、过温度、短路等多重保护功能。
和其它电源不同的是，多彩极冻电源采用了一块半导体制冷片．是国内首款采用半导体制冷片进行散热的电源产品。
【总页数】1页(P14)
【正文语种】中文
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1.智能散热有一套——多彩320A电源简介 [J],
2.电源也玩半导体散热——多彩ICE CUBE-550极冻电源 [J], 雷军
3.香港理工大学获安森美半导体赞助勇夺国际电源设计挑战赛大奖：得奖作品采用安森美半导体节能开关电源模式电源控制芯片 [J],
4.用做板卡的精神做电源、散热器华硕电脑电源、散热器部门高层专访摘要 [J], MC[1];杨承翰[1];吴卓刚[1];陈列[1]
5.599元的550W电源极冻酷凌冰川GP-PS550BP电源 [J],
因版权原因，仅展示原文概要，查看原文内容请购买。
英伟达超算中心浸没式冷却液方案
英伟达超算中心浸没式冷却液方案一、引言随着科技的进步，超级计算机已经成为许多科学领域研究、工程模拟和数据处理的基础工具。
然而，随着计算机性能的提高，散热问题也变得愈发突出。
因此，设计一套高效可靠的冷却液方案变得至关重要。
本文将采用英伟达超算中心作为实际案例，详细介绍一种浸没式冷却液方案。
二、方案设计1.冷却液的选择冷却液是浸没式冷却系统的核心。
为了保证高效的散热效果，我们推荐选用液态冷却剂。
液态冷却剂的热导率较高，并且具有良好的散热性能。
同时，冷却液还需具备良好的绝缘性能，以保证设备的运行安全。
我们推荐选用高纯度无水醇类冷却液作为基础液体，并根据实际需求加入合适的添加剂，如界面活性剂和抗菌剂。
2.浸没式冷却系统的设计为了实现浸没式冷却效果，需在超级计算机的整个设备上方设计一层浸没式冷却池。
冷却池的材质应选用具有良好耐腐蚀性和绝缘性的材料，如陶瓷。
冷却池应具备良好的密封性能，确保冷却液不会泄漏。
在冷却池底部，设计一套循环冷却系统，将冷却池中的液体通过冷却装置循环使用，保持流动的冷却液始终保持较低的温度，从而实现设备的散热效果。
3.传感器与控制系统在浸没式冷却液方案中，传感器和控制系统是非常重要的一部分。
通过在冷却池中布置温度传感器，可以实时监测冷却液的温度情况，并将数据反馈给控制系统。
控制系统将根据温度情况，自动调节冷却液的循环速度和冷却设备的功率，使冷却液的温度保持在合适范围内。
同时，控制系统还需要具备报警功能，当冷却液温度异常时，及时发出警报，以避免过高温度对设备的损坏。
4.安全与环保考虑在浸没式冷却液方案中，安全性和环保性是非常重要的考虑因素。
首先，冷却液的选用应遵循环保原则，选择无毒、无害的冷却液。
其次，在冷却池和循环系统中，需设置过滤装置，保证冷却液中不会存在杂质和颗粒，以避免对设备的损害。
此外，在冷却系统中还需设置流量监测装置，当冷却液流动异常时，及时报警并停止运行，以避免进一步的损害。
Allied Precision Industries, Inc. 冰膜电泵模型7521、7621、
3. Some animals--particularily horses--may try to remove the deicer from the tank. To counteract this, you may wish to run the cord through PVC or galvanized tubing extending over the tank or use the API Deicer Safety Tether Model 23ST. Be sure to allow slack in the cord to compensate for varying water level.
- To test the unit: Place the de-icer in a freezer for 20 minutes to make sure that the thermostat is turned on. Locate a GFCI outlet (typically found in a bathroom in newer homes) and run some water into a bucket, sink, or bathtub near the outlet. Quickly remove the unit from the freezer, place it into the water, and plug the unit into the GFCI while taking care not to touch the water. If the unit trips the GFCI, it is defective and should be returned to the place of purchase. If it does not trip the GFCI, it is operating properly and is not leaking electricity to the water. However, there could be electricity entering the tank via the ground wire due to presence of voltage on the ground circuit in the electrical supply from the building. Many times, this voltage is coming directly from the electric utility company. For help with this problem, contact Allied Precision at (800) 627-6179 or (630) 365-0340.
一种适合宽范围输出的双向DC-DC变换器
第28卷㊀第2期2024年2月㊀电㊀机㊀与㊀控㊀制㊀学㊀报Electri c ㊀Machines ㊀and ㊀Control㊀Vol.28No.2Feb.2024㊀㊀㊀㊀㊀㊀一种适合宽范围输出的双向DC-DC 变换器袁义生,㊀卢梓意,㊀刘伟(华东交通大学电气与自动化工程学院,江西南昌330013)摘㊀要:提出一种适合宽范围输出的双向DC-DC 变换器㊂该变换器结构与传统LLC 双向DC-DC 变换器类似,但通过开关管复用以及将谐振电感增加绕组复用为一个反激变压器,构造了多种工作模式㊂变换器采用PWM 调制,正向功率传输时有中㊁低两种电压增益模式,反向功率传输时有高㊁中㊁低三种电压增益模式,所有模式中均可实现全负载范围内的软开关状态㊂对各模式的工作原理㊁增益公式推导进行了详细的描述㊂最后以满足4-5节12V 蓄电池的充放电为前提,给出变换器设计和控制方法,并搭建了相应参数的实验样机㊂实验结果验证了该变换器分析的有效性㊂关键词:双向DC-DC 变换器;宽范围;多模式;谐振;软开关DOI :10.15938/j.emc.2024.02.015中图分类号:TM46文献标志码:A文章编号:1007-449X(2024)02-0152-10㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀收稿日期:2022-05-23基金项目:国家自然科学基金(52067007);江西省自然科学基金重点项目(20232ACB204024)作者简介:袁义生(1974 ),男,博士,教授,博士生导师,研究方向为电力电子系统及其控制;卢梓意(1996 ),男,硕士,研究方向为电力电子与电力传动;刘㊀伟(1985 ),男,博士研究生,研究方向为电力电子与电力传动㊂通信作者:袁义生Bidirectional DC-DC converter suitable for wide output rangeYUAN Yisheng,㊀LU Ziyi,㊀LIU Wei(School of Electrical and Automation Engineering,East China Jiaotong University,Nanchang 330013,China)Abstract :A bidirectional DC-DC converter suitable for wide range output was proposed.The structure of the converter is similar to that of the traditional LLC bi-directional DC-DC converter,but a variety of op-erating modes were constructed by multiplexing the switching and multiplexing the resonant inductor in-creasing winding as a flyback transformer.In the converter,by adopting PWM modulation,forward power transmission has medium and low voltage gain mode,reverse power transmission has high,medium and low voltage gain mode,all modes can achieve the soft switching state within the full load range.The working principle of each mode and derivation of gain formula are described in detail.Finally,on the premise of charging and discharging 4-512V batteries,the design and control method of the converter is given,and the experimental prototype of the corresponding parameters is built.Experimental resultsverify the effectiveness of the proposed converter analysis.Keywords :bidirectional DC-DC converter;wide range;multi-mode;resonance;soft switching0㊀引㊀言近年来,随着直流配电[1-3]和电动汽车直流充电桩[4-5]技术的迅速发展,功率能够双向流动的DC-DC 变换器也得到了越来越多的研究,尤其是能够适应宽输入或宽输出电压范围工作的高效率㊁高电压增益的双向DC-DC 变换器㊂传统的双半桥或者双全桥双向DC-DC 变换器[6-7]具有软开关的优点,但缺点是正㊁反向电压增益都小于1,且关断时刻电流大㊁循环损耗大㊂LLC 谐振型双向DC-DC变换器[8]能够更好地实现软开关且关断电流和循环损耗更小,在正向工作时电压增益能大于1,但一般小于1.4;缺点是反向电压增益小于1,正向工作时开关频率调节范围过宽㊂双向CLLC谐振变换器[9]进一步提升反向电压增益大于1,但缺点是使用器件太多,功率密度较低,且开关频率调节范围过宽㊂带辅助电感的对称式双向LLC谐振变换器[10]比CLLC谐振变换器减小了一个谐振电容,但开关频率范围仍然较宽㊂文献[11]通过在二次侧增加一个双向交流开关,在保持高效的同时可以通过PWM调制增加变换器的电压调节能力,但是这增加了成本和复杂性㊂提高DC-DC变换器的电压增益范围有以下几种方案㊂1)调节谐振腔参数㊂文献[12]通过降低励磁电感使电路在低k值下运行,实现功率高密度㊂文献[13]采用一种充磁电感,在不同的模式中通过改变频率进而改变电感量,可以将导通损耗降到最低并且提高电压增益㊂2)引入辅助桥臂㊂文献[14]在原边增加了辅助双向开关桥臂让电路可以在常态运行和掉电保持运行之间切换,保证了输出电压稳定也提高了工作效率㊂文献[15]通过引入辅助桥臂,增加充能环节,有多种工作模式,拓宽了增益范围进㊂3)新型调制策略㊂文献[16-17]为了限制开关频率的变化并获得较宽的电压增益范围,提出了适用于低谐振变换器的恒频移相控制方法,但变换器在低电压增益或者轻载的情况下会失去零电压开关(ZVS)㊂文献[18-20]采用新型控制策略通过在全桥模式和半桥模式之间切换实现了较宽增益的输出㊂4)改变谐振腔电压㊂文献[21]提出的复合型谐振变换器通过复用谐振电感来提高功率密度,利用多种模态实现全负载下的宽增益输出㊂文献[22]采用两个变压器串联,有四种运行方式,可以覆盖最小输入电压的四倍范围,并且通过优化电路参数来达到较高的效率㊂本文通过器件复用,提出一种结构更简单,具有多种电压增益模式的双向宽范围输出的DC-DC变换器㊂该变换器采用PWM调制,开关频率固定,具有全软开关高效率的优点㊂1㊀拓扑结构及工作原理1.1㊀拓扑结构及工作状态图1为本文提出的适合宽范围输出的双向DC-DC变换器㊂该变换器左右侧均采用全桥结构,由8个开关管S1~S8及其反并二极管和寄生电容构成,通过一个原副边匝比为K1的主变压器T1隔离,是一个传统的桥式双向DC-DC变换器结构㊂此外,还有一个原副边匝比为K2的辅助变压器T2和开关管S9及其反并二极管D9,构成了一个反激双向DC-DC 变换器㊂辅助变压器T2的原边绕组电感L r复用作谐振电感,与谐振电容C r构成谐振腔㊂L m为T1的励磁电感,假设L m极大㊂图1㊀提出的适合宽范围输出的双向DC-DC变换器Fig.1㊀A wide gain multi-mode bidirectional DC-DC converter proposed提出的双向DC-DC变换器有正向功率传输和反向功率传输两种工作方式㊂正向工作时有中㊁低电压增益两种模式,反向工作时有高㊁中㊁低三种电压增益模式,适用于宽范围输出的场合㊂定义特征阻抗Z r=L r/C r,品质因数Q=π2Z r/(8K2R o),谐振频率f r=1/(2πL r C r),开关频率f s,归一化频率f n=f s/f r,谐振角频率ωr= 2πf r㊂1.2㊀正向功率传输方式及工作原理正向功率传输方式时,功率从左侧向右侧传输,有中㊁低两种电压增益模式㊂1.2.1㊀正向中电压增益模式正向中电压增益(forward medium gain,FMG)模式采用脉冲宽度调制(pulse width modulation,PWM)调制,关键波形如图2所示㊂S1㊁S6㊁S7为第一组, S2㊁S5㊁S8为第二组,每组共同导通关断,两组开关管互补导通,占空比为D=[2(t1-t0)/T s]㊂S3㊁S4也是互补导通并且分别和第一组和第二组开关管同时开通,占空比接近0.5㊂一个开关周期分为三个阶段如图3所示,下面对三个阶段进行详细描述㊂351第2期袁义生等:一种适合宽范围输出的双向DC-DC变换器阶段1[t 0-t 1]:LC 谐振阶段㊂t 0时刻S 1和S 4导通,副边S 6和S 7和二极管D 6㊁D 7导通,形成LC 谐振回路㊂电容电压最大为ΔU Cr ,则此阶段副边的电感电流i Lr_F 可以表示为i Lr_F (t )=U i /K 1-U o +ΔU CrZ rsin(ωr t )㊂(1)本阶段通过LC 谐振从左到右传递能量㊂图2㊀FMG 模式的主要波形Fig.2㊀Main waveforms of FMGmode图3㊀FMG 模式各阶段的等效电路Fig.3㊀Equivalent circuits of each stage of FMG mode阶段2[t 1-t 2]:环流阶段㊂t 1时刻S 1㊁S 6㊁S 7关断,D 3迅速导通㊂由于谐振电感电流i Lr_F 不能突变,电容电流i Cr 会瞬间换向通过二极管D 5㊁D 8流向L r ㊂此阶段电容电压U Cr 近似不变,T 1原边短路谐振电感L r 承受(U o -U cr )的反向电压,谐振电流i Lr_F 直线下降㊂变压器电流i Lm 快速下降接近至0再反向㊂此阶段的电感电流i Lr_F 可以表示为i Lr_F (t )=i Lr_F (t 1)-U o +ΔU CrL r(t -t 1)㊂(2)本阶段原边环流,副边换流,L r 继续释放能量㊂阶段3[t 2-t 3]:死区阶段㊂t 2时刻S 4关断,原边电流通过D 2㊁D 3流向电源U i ,此时L r 承受[(U i /n 1)+U Cr -U o ]的正向电压,电流迅速上升㊂至t 3时刻,S 2㊁S 3㊁S 5㊁S 8均实现ZVS 开通㊂本阶段作用时间很短㊂1.2.2㊀正向低电压增益模式正向低电压增益(forward low gain,FLG)模式采用PWM 调制,仅开关管S 9工作,通过控制其占空比D f 来实现电压转换㊂开关管S 9和T 2以及右侧四个二极管构成了一个反激变换器,具体工作原理不再赘述㊂1.3㊀反向功率传输方式及工作原理反向功率传输时,输入电压为U o ,输出电压为U i ,有高㊁中㊁低三种电压增益模式㊂1.3.1㊀反向高电压增益模式反向高电压增益(reverse high gain,RHG)模式关键波形如图4所示㊂各开关管采用PWM 调制㊂副边两个上管S 5和S 6互补导通,(t 3-t 2)为两者间死区时间;两个下管S 7和S 8的导通占空比相等且大于0.5,它们分别与S 6和S 5同时触发导通㊂原边的开关管S 1㊁S 4和S 6同时开通关断,S 2㊁S 3和S 5同时导通关断㊂图4㊀RHG 模式的主要波形Fig.4㊀Main waveforms of RHG mode451电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第28卷㊀RHG 模式通过调整同一桥臂上下管共同导通的占空比D b =[2(t 1-t 0)/T s ]来调节增益㊂以下分析上半个周期[t 0-t 4]的4个工作阶段原理,其等效电路图如图5所示㊂图5㊀RHG 模式各阶段的等效电路Fig.5㊀Equivalent circuits of each stage of RHG mode1)阶段1[t 0-t 1]:Boost 阶段㊂t 0之前i Lr 初始值为0㊂此阶段S 6和S 8导通,电源U o 给谐振电感L r 储能,i Lr 线性上升㊂由于i Lr 初始值为0,所以实现了S 1㊁S 4㊁S 6㊁S 7㊁S 8的ZCS 开通㊂至t 1时刻,电感电流i Lr 上升为i Lr (t 1)=U o D b T sL r㊂(3)本阶段实现了L r 的储能㊂2)阶段2[t 1-t 2]:LC 谐振阶段㊂t 1时刻关断S 8,此时S 6㊁S 7导通,原边S 1㊁S 4㊁D 1㊁D 4导通,进入L r 和C r 谐振阶段㊂C r 初始电压为-U CrM ㊂此阶段谐振电流i Lr 和谐振电压U cr 分别表示为i Lr (t )=U o -U i /K 1+U CrMZ rsin[ωr (t -t 1)]+i Lr (t 1)cos[ωr (t -t 1)];(4)U Cr (t )=i Lr (t 1)Z r sin[ωr (t -t 1)]+U o -K 1U i -(U o -K 1U i +U CrM )cos[ωr (t -t 1)]㊂(5)本阶段通过LC 谐振从右到左传递能量㊂3)阶段3[t 2-t 3]:Flyback 阶段㊂t 2时刻关断S 6㊁S 1㊁S 4,S 7继续导通㊂此时L r 上的能量通过变压器T 2反激传输到U i 侧㊂反激电流为i f =K 2i Lr (t 2)-K 2U iL r(t -t 2)㊂(6)本阶段通过反激方式将L r 的剩余能量全部传递到原边㊂4)阶段4[t 3-t 4]:电流断续阶段㊂t 3时刻i f 下降至0,直至t 4时刻开始下半个周期㊂1.3.2㊀反向中电压增益模式反向中电压增益(reverse medium gain,RMG)模式关键波形如图6所示㊂各开关管采用传统的PWM 调制㊂副边的S 6㊁S 7,和原边的S 1㊁S 4为一组;副边的S 5㊁S 8,和原边的S 2㊁S 3为另一组㊂两组开关管导通占空比都是D m =[2(t 1-t 0)/T s ],导通时刻相差180ʎ㊂图6㊀RMG 模式的主要波形Fig.6㊀Main waveforms of RMG modeRMG 模式相比RHG 模式仅少了一个Boost 阶段㊂[t 0-t 3]是上半个周期的3种工作阶段,各阶段工作原理简述如下:1)阶段1[t 0-t 1]:LC 谐振阶段㊂此阶段工作原理等同于RHG 模式的LC 谐振阶段,区别仅在于谐振电感初始电流i Lr 为0,使得S 6㊁S 7实现ZCS 导通㊂2)阶段2[t 1-t 2]:Flyback 阶段㊂此阶段工作551第2期袁义生等:一种适合宽范围输出的双向DC -DC 变换器原理等同于RHG模式的Flyback阶段㊂3)阶段3[t2-t3]:电流断续阶段㊂此阶段工作原理等同于RHG模式电流断续阶段㊂1.3.3㊀反向低电压增益模式反向低电压增益(reverse low gain,RLG)模式采用PWM调制,右侧四个开关管S5-S8同时通断,通过控制其占空比D f来实现电压转换㊂这四个开关管和T2㊁D9构成了一个反激变换器,具体工作原理不再赘述㊂2㊀电压增益2.1㊀FMG模式电压增益G FMG本模式本质上等同于一个副边LC谐振变换器,因此其电压增益最大为1㊂推导如下㊂定义本模式电感电流i Lr_F在LC谐振阶段的平均值为I d_F,在Flyback阶段的平均值为I f_F,负载电阻为R o,则G FMG=U o Ui =R o(I d_F+I f_F)U i㊂(7)I d_F和I f_F可以表示为I d_F=2f sʏt1t0i Lr_F(t)d t=πU i(1/K1-G FMG)[1-cos(πD)][3+cos(πD)]8QR o[1+cos(πD)];(8)I f_F=2f sʏt3t1i Lr_F(t)d t=πU i sin2(πD)(1/K1-G FMG)2[3+cos(πD)]216QR o[2/K1-G FMG+cos(πD)][1+cos(πD)]㊂(9)联合式(7)㊁式(8)㊁式(9)可以得到有关G FMG㊁D㊁Q的隐函数f FMG(G FMG,D,Q)=8QG FMG[1+cos(πD)]-π(1-G FMG)ˑ[3+cos(πD)]{1-cos(πD)+sin2(πD)(1/K1-G FM G)[3+cos(πD)]2[2/K1-G FM G+cos(πD)]}㊂(10)根据式(10)绘出G FMG曲线如图7所示㊂可以看出,随着占空比D增大,最大增益接近1,并且能够在较大Q值下保持较好的线性调节能力㊂2.2㊀FLG模式电压增益G FLG本模式本质是一个工作在电流断续状态的反激变换器,其电压增益为G FLG=K2D f R oT s2L r㊂(11)图7㊀FMG模式的电压增益曲线Fig.7㊀Gain curve of FMG mode2.3㊀RHG模式电压增益G RHG本模式实质等同于Boost+副边LC谐振+Fly-back变换器,因此其最大增益大于1且易受Boost 阶段控制㊂定义本模式输出电流在LC谐振阶段的平均值为I d_R,在Flyback阶段的平均值为I f_R㊂总的输出电流平均值I i为I d_R和I f_R之和,U i侧负载电阻为R i㊂则㊀G RHG=U i Uo=R i(I d_R+I f_R)U o;(12)㊀I d_R=2K1f sʏt2t1i Lr(t)d t=2K1U o{(1-K1G)[1-cos(D m-D b)]+πD b sin(D m-D b)+2πD b[1-sin(1-D d)]}/{πZ r[1+cos(D m-D b)]};(13)㊀I f_R=2K1f sʏt2t1i f_R(t)d t=L r f s i2Lr(t2)K2U i㊂(14)将式(13)㊁式(14)代入到式(12)得到有关G RHG㊁D m㊁D b㊁Q的隐函数f RHG(G RHG,D m,D b,Q)=π8K21Q{1+cos[π(D m-D b)]}ˑ{2K1πD b sin[π(D m-D b)]+4K1πD b{1-sin(πD m)}+2K1(1-K1G RHG){1-cos[π(D m-D b)]}+12K2G RHG{1+cos[π(D m-D b)]}ˑ{πD b{1+cos[π(D m-D b)]}+2(1-K1G RHG)sin[π(D m-D b)]+2πD b{1-sin[π(D m-D b)]}ˑsin[π(D m-D b)]}2}-G RHG㊂(15)651电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第28卷㊀2.4㊀RMG模式电压增益G RMGRMG无RHG模式的Boost阶段,将D b=0代入式(15)得到G RMG的隐函数f RMG(G RMG,D m,Q)=G RMG-π(1-K1G RMG)4K2K21QG RMGˑ1-cos(πD m)1+cos(πD m)㊂(16)根据式(15)㊁式(16)绘出G RHG和G RMG的特性曲线如图8所示㊂图中实线表示G RMG与Q值和D m 的关系,D m在0~0.8之间调节㊂图8中虚线表示G RHG㊁Q值和D b的关系,D b在0~0.4范围之间调节㊂在D b到达0.2时G RHG就达到1.4,超过传统LLC谐振型DC-DC变换器的增益㊂图8㊀RHG和RMG模式的特性曲线Fig.8㊀Characteristic curves of RHG and RMG modes 2.5㊀RLG模式电压增益G RLG本模式本质是一个工作在电流断续状态的反激变换器,电压增益G RLG=D f K2R i T s2L r㊂(17)3㊀所提变换器的设计设计一个可以对4-5节额定电压为12V的蓄电池组进行充放电的双向DC-DC变换器,其充电电压为55.4~73.5V,放电电压为42~73.5V,设计参数见表1㊂3.1㊀正反向电压增益假设实际需求双向DC-DC变换器最大正向增益为G F,最大反向增益为G R,当主变压器变比K1= 1时双向DC-DC变换器能达到的最大正向增益为G1,最大反向增益为G2,则设计的双向DC-DC变换器的变比K须满足以下条件:G Fɤ1K G1;G RɤKG2㊂}(18)即G RG2ɤKɤG1G F㊂表1㊀设计的参数范围Table1㊀Experimental scope of the design 工作方式实验参数㊀㊀㊀取值正向工作方式输入电压U i/V220额定输出电压/V60额定功率P o/W450输出电压范围U o/V30~73.5开关频率f s/kHz100反向工作方式输入电压U o范围/V42~73.5输出电压U i/V220额定输入电压/V60额定功率P o/W450开关频率f s/kHz100要使电路能达到实际需求,则K1值要有解,所以电路增益要满足G1G2ȡG F G R㊂(19)根据表1得到G F=0.3,G R=5.2㊂代入公式(18),有G1G2ȡ1.56㊂而根据图7和图8所示,本文所提电路只要选择合适的参数,能较容易满足该双向增益条件㊂此处选择G FMG=G1=0.98,G RHG=G2=1.75㊂3.2㊀变压器匝比设计选择好G FMG和G RHG后,设计K1=3㊂设计K2= 1,使变换器在双向工作时均能在Flyback阶段将电感剩余能量馈到负载端㊂3.3㊀品质因数和最大占空比将0.9G RMG设为额定增益G o,则在实际工作增益小于G o时是中增益模式,大于G o时切换成高增益模式㊂定义额定增益下的品质因数Q o=0.2,根据式(15)和式(16),计算得到最大占空比D m_max= 0.8㊂3.4㊀谐振参数设计根据f r和Q o来设计L r和C r,有:751第2期袁义生等:一种适合宽范围输出的双向DC-DC变换器L r =8U 2i G 2o Q oπ2ωs P i;C r =π2P i8U 2i G 2o ωs Q o㊂üþýïïïï(20)其中:P i 为额定功率;角频率ωs =2πf s ㊂将各参数代入上述公式可得:L r =22.5μH;C r =112.6nF㊂4㊀实验分析为了验证提出的双向DC-DC 变换器,制作了一台实验样机,实物照片如图9所示㊂样机工作参数见表1,其他参数如表2所示㊂图9㊀样机实物照片Fig.9㊀Photo of prototype表2㊀实验参数Table 2㊀Experimental parameters器件参数㊀数值主变压器T 1匝比K 13原边电感/漏感810μH /0.2μH 副边电感/漏感90μH /0.2μH 辅助变压器T 2匝比K 21原边电感L r /漏感22μH /0.6μH 副边电感/漏感22μH /0.6μH谐振电容C r 谐振电容C r 110nF 开关管IRF4609个所提变换器采用了最简单的单电压环控制,各个工作模式的切换通过对电压环的输出数值设置不同的阀值进行切换㊂4.1㊀正向工作关键波形设计的双向DC-DC 变换器正向工作范围为输入电压220V,输出电压30~73.5V㊂图10~图12分别为输入电压U i =220V 时,FMG 和FLG 模式下输出电压U o =73.5㊁55.4㊁30V的关键波形㊂图10㊀FMG 模式下73.5V 输出关键波形Fig.10Key waveforms with 73.5V output in FMGmode图11㊀FMG 模式下55.4V 输出关键波形Fig.11㊀Key waveforms with 55.4V output in FMG mode图10为U i =220V㊁U o =73.5V 时,FMG 模式下的关键波形㊂此时的电感电流连续,电容电流i Cr在开关管关断时进行换向,在下一次开关管导通之前与电感电流i Lr 保持一致并进行谐振直到下一次开关管关断进行换流㊂851电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第28卷㊀图12㊀FLG 模式下30V 输出关键波形Fig.12㊀Key waveforms with 30V output in FLG mode图11为U i =220V㊁U o =55.4V 时,FMG 模式下的关键波形㊂图12为U i =220V㊁U o =30V 时,FLG 模式下的关键波形,此时反激占空比D f =0.2㊂电路工作在DCM 模式㊂4.2㊀反向工作关键波形设计的双向DC-DC 变换器反向工作范围为输入电压42~73.5V,输出电压220V㊂图14~图15分别为输入电压U o =42V㊁73.5V 时,RHG 和RMG 模式下输出电压U i =220V 的关键波形㊂图13㊀RHG 模式下220V 输出关键波形Fig.13㊀Key waveforms with 220V output in RHG mode图13为U o =42V㊁U i =220V 时RHG 模式下的关键波形,此时D b =0.35㊂由图可知,电感电流i Lr 在Boost 阶段线性上升,随后和谐振电容C r 进行谐振㊂在S 5和S 6关断时谐振电感电流i Lr 会以Fly-back 的模式通过T 2变压器流到负载端㊂i Lr 会在周期内复位,可以实现ZCS 开通㊂工作在RHG 模式下,电路只有谐振阶段和Flyback 阶段两个阶段向负载馈能㊂图14㊀RMG 模式下220V 输出关键波形Fig.14㊀Key waveforms with 220V output in RMG mode图14为U o =73.5V㊁U i =220V 时RMG 模式下的关键波形,此时占空比D m =0.8㊁㊂相比RHG 模式,RMG 模式没有Boost 阶段,其谐振及软开关过程均与反向HG 模式相同㊂当输出电压降低使得D m 小于0.55时,电路会工作在RLG 模式下,提高电路的效率㊂4.3㊀切载波形及效率曲线图15为电路随负载变化而切换工作模式的动态响应波形㊂图16为提出的双向DC-DC 变换器和传统LLC 谐振双向DC-DC 变换器[8]在U o =60V 的条件下,正向㊁反向工作的效率曲线㊂为了提高传统LLC 谐振双向DC-DC 变换器的电压增益,实验时将其变压器励磁电感减小到50μH㊁漏感增大到10μH,其余参数与提出的变换器一致㊂由图17可见,传统双向DC-DC 变换器最高效率为88.32%,提出的变换器整体效率高于传统双向变换器,且工作在额定功率450W 时达到最高效率94.56%㊂951第2期袁义生等:一种适合宽范围输出的双向DC -DC 变换器图15㊀负载切换动态响应波形Fig.15㊀Dynamic response waveform with loadswitching图16㊀不同工作方式的效率曲线Fig.16㊀Efficiency curves with different modes5㊀结㊀论本文提出了一种适合宽范围输出的双向DC-DC 变换器,该变换器具体有以下几个优点:1)正向功率传输有两种电压增益模式,反向功率传输有三种电压增益模式,适合宽范围电池充放电场合,有较高的最高电压增益;2)采用定频PWM 调制,磁性器件设计简单;3)低增益模式的反激变压器的电感复用做中高增益模式的LC 谐振的谐振电感,提高了电路的功率密度;4)全负载范围内均实现了软开关,降低了开关损耗㊂参考文献:[1]㊀李建国,赵彪,宋强,等.直流配电网中高频链直流变压器的电压平衡控制策略研究[J ].中国电机工程学报,2016,36(2):327.LI Jianguo,ZHAO Biao,SONG Qiang,et al.DC voltage balance control strategy of high frequency link DC transformer in DC distri-bution system[J].Proceedings of the CSEE,2016,36(2):327.[2]㊀SHE X,HUANG A Q,BURGOS R.Review of solidstate trans-former technologies and their application in power distribution sys-tems[J].IEEE Journal of Emerging &Selected Topics in Power E-lectronics,2013,1(3):186.[3]㊀熊雄,季宇,李蕊,等.直流配用电系统关键技术及应用示范综述[J].中国电机工程学报,2018,38(23):6802.XIONG Xiong,JI Yu,LI Rui,et al.An overview of key technology and demonstration application of DC distribution and consumption system[J].Proceedings of the CSEE,2018,38(23):6802.[4]㊀ZHENG Zhong,ZHANG Daifang.Study on electromagnetic com-patibility of DC charging pile[C]//2018China International Con-ference on Electricity Distribution (CICED),September 17-19,2018,Tianjin,China.2018:2805-2810.[5]㊀CHEN Zhiru,LI Xinguang,DONG Xianguang,et al.Researchon remote calibration system of DC metering device for electric ve-hicle charging piles based on embedded[C]//2019IEEE 3rd In-formation Technology,Networking,Electronic and Automation Control Conference,March 15-17,2019,Chengdu,China.2019:300-304.[6]㊀CHOI B Y,NOH Y S,JI Y H,et al.Battery-integrated power op-timizer for PV-battery hybrid power generation system[C]//IEEE Vehicle Power and Propulsion Conference,October 9-12,2012,Seoul,Korea.2012:1343-1348.[7]㊀KRISMER F,KOLAR W J.Efficiency-optimized high-current du-al active bridge converter for automotive applications.[J].IEEE Transactions on Industrial Electronics,2012,59(7):2745.[8]㊀PLEDL G,TAUER M,BUECHERL D.Theory of operation,de-sign procedure and simulation of a bidirectional LLC resonant con-verter for vehicular applications[C]//2010IEEE Vehicle Power and Propulsion Conference,September 1-3,2010,Lille,France.2011:1-5.[9]㊀JUNG J H,KIM H S,RYU M H,et al.Design methodology ofbidirectional CLLC resonant converter for high-frequency isolation of DC distribution systems[J].IEEE Transactions on Power Elec-tronics,2013,28(4):1741.[10]㊀WU H,DING S,SUN K,et al.Bidirectional soft-switching se-ries-resonant converter with simple PWM control and load-inde-pendent voltage-gain characteristics for energy storage system in DC microgrids[J].IEEE Journal of Emerging &Selected Topicsin Power Electronics,2017,5(3):995.[11]㊀LABELLA T,YU W,LAI J S,et al.A bidirectional-switch-based wide-input range high-efficiency isolated resonant converter for photovoltaic applications[J].IEEE Transactions on Power E-061电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第28卷㊀lectronics,2014,29(7):3473.[12]㊀JEONG Y,MOON G W,KIM J K.Analysis on half-bridge LLCresonant converter by using variable inductance for high efficiencyand power density server power supply[C]//IEEE Applied Pow-er Electronics Conference&Exposition,March26-30,2017,Tampa,FL,USA.2017:170-177.[13]㊀KIM D K,MOON S C,YEON C O,et al.High-efficiency LLCresonant converter with high voltage gain using an auxiliary LCresonant circuit[J].IEEE Transactions on Power Electronics,2016,31(10):6901.[14]㊀杨东江,段彬,丁文龙,等.一种带辅助双向开关单元的宽输入电压范围LLC谐振变换器[J].电工技术学报,2020,35(4):775.YANG Dongjiang,DUAN Bin,DING Wenlong,et al.An improvedLLC resonant converter with auxiliary bi-directional switch forwide-input-voltage range applications[J].Transaction of Electro-technical Society,2020,35(4):775.[15]㊀袁义生,梅相龙,张伟先等.一种混合调制的五电平LLC谐振变换器[J].电机与控制学报,2020,24(6):107.YUAN Yisheng,MEI Xianglong,ZHANG Weixian.Five-levelLLC resonant converter with mix-modulation method[J].ElectricMachines and Control,2020,24(6):107.[16]㊀MCDONALD B,WANG F.LLC performance enhancements withfrequency and phase shift modulation control[C]//Applied Pow-er Electronics Conference&Exposition,March16-20,2014,TX,USA.2014:2036-2040.[17]㊀HARISCHANDRAPPA N,BHAT A K S.A fixed-frequencyLCL-type series resonant converter with capacitive output filter u-sing a modified gating scheme[J].IEEE Transactions on Indus-try Applications,2014,50(6):4056-4064. [18]㊀LIANG Z,GUO R,WANG G,et al.A new wide input rangehigh efficiency photovoltaic inverter[C]//IEEE Energy Conver-sion Congress and Exposition,September12-16,2010,Atlan-ta,GA,USA.2010:2937-2943.[19]㊀廖政伟,张雪,尤伟,等.应用于超宽输入范围的变拓扑LLC电路[J].浙江大学学报(工学版),2013,47(12):2073.LIAO Zhengwei,ZHANG Xue,YOU Wei,et al.Variable LLC cir-cuit used in ultra-wide input voltage range[J].Journal of Zhe-jiang University(Engineering Science),2013,47(12):2073.[20]㊀谢晶晶,吕征宇.应用于宽输入范围的变模态LLC电路设计[J].电源学报,2016,14(3):20.XIE Jingjing,LÜZhengyu.Variable modal LLC circuit used indesign of wide input voltage range[J].Journal of Power Supply,2016,14(3):20.[21]㊀袁义生,赖立.一种适用于宽范围输出的复合谐振型全桥变换器[J].中国电机工程学报,2020,40(20):6694.YUAN Yisheng,LAI li.A compound resonant full-bridge convert-er suitable for wide range output[J].Proceedings of the CSEE,2020,40(20):6694.[22]㊀HU H,FANG X,CHEN F,et al.A modified high-efficiency LLCconverter with two transformers for wide input-voltage range appli-cations[J].IEEE Transactions on Power Electronics,2013,28(4):1946.(编辑:刘素菊)161第2期袁义生等:一种适合宽范围输出的双向DC-DC变换器。
直流母线单电流传感器零点漂移误差自校正策略
第27卷㊀第7期2023年7月㊀电㊀机㊀与㊀控㊀制㊀学㊀报Electri c ㊀Machines ㊀and ㊀Control㊀Vol.27No.7Jul.2023㊀㊀㊀㊀㊀㊀直流母线单电流传感器零点漂移误差自校正策略申永鹏1,㊀王前程1,㊀王延峰1,㊀梁伟华1,㊀孟步敏2(1.郑州轻工业大学电气信息工程学院,河南郑州450000;2.湘潭大学信息工程学院,湖南湘潭411100)摘㊀要:为了研究三相两电平逆变器中直流母线单电流传感器零点漂移对相电流重构精确度的影响,阐明了直流母线单电流传感器相电流重构原理,对比了多电流传感器与单电流传感器零点漂移误差,揭示了零点漂移误差产生的原因及扩大效应的产生机理,基于插入互补有效电压矢量代替零矢量的空间矢量脉冲宽度调制方法,提出了零点漂移误差自校正策略㊂分析了各扇区电流观测窗口时长,利用互补有效电压矢量动态电流双采样,实现了相电流重构与电流零点漂移量的自检测和自校正㊂搭建了基于TMS320F28035型DSP 为电驱动控制器的实验平台,在额定转速以内的工况下,自校正后的重构相电流误差小于3.56%,表明了所提误差自校正策略能为控制系统提供可靠的重构电流㊂关键词:三相两电平逆变器;直流母线;单电流传感器;互补矢量;相电流重构;误差自校正DOI :10.15938/j.emc.2023.07.014中图分类号:TM341文献标志码:A文章编号:1007-449X(2023)07-0133-10㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀收稿日期:2021-08-20基金项目:国家自然科学基金(52177068,61803345,51807013);河南省科技攻关项目(202102210303)作者简介:申永鹏(1985 ),男,博士,副教授,研究方向为电动汽车动力系统驱动与控制㊁能量管理与优化;王前程(1996 ),男,硕士研究生,研究方向为电动汽车动力系统驱动与控制;王延峰(1973 ),男,博士,教授,研究方向为智能电器与信息处理;梁伟华(1988 ),男,博士,讲师,研究方向为电力电子变化技术;孟步敏(1987 ),男,博士,讲师,研究方向为电动汽车整车控制㊂通信作者:王前程Self-correction strategy of zero-point drift error of DC bus singlecurrent sensorSHEN Yongpeng 1,㊀WANG Qiancheng 1,㊀WANG Yanfeng 1,㊀LIANG Weihua 1,㊀MENG Bumin 2(1.College of Electrical and Information Engineering,Zhengzhou University of Light Industry,Zhengzhou 450000,China;2.School of Information Engineering,Xiangtan University,Xiangtan 411100,China)Abstract :In order to study the influence of the zero drift of the DC bus single current sensor on the phase current reconstruction accuracy in the three-phase two-level inverter,the principle of the phase current reconstruction of the DC bus single current sensor was clarified,and the multi-current sensor and the sin-gle current sensor were compared.The zero drift error reveals the cause of the zero drift error and the mechanism of the amplification effect.Based on the space vector pulse width modulation method of inser-ting complementary effective voltage vectors instead of zero vectors,a self-correction strategy for zero drift errors was proposed.The current observation window duration of each sector was analyzed,and the phase current reconstruction and the self-detection and self-correction of the current zero-point drift were real-ized by using the complementary effective voltage vector dynamic current double sampling.A control sys-tem experiment platform with TMS320F28035DSP as the electric drive controller was built.Under the working conditions within the rated speed,the error of the reconstructed phase current after self-calibra-tion is less than 3.56%,which shows that the proposed error self-calibration strategy can provide reliablereconstructed current for the control system.Keywords:three-phase two-level inverter;DC bus;single current sensor;complementary vector;phase current reconstruction;error self-correction0㊀引㊀言交流电驱动控制系统在现代工业装备中运用广泛,精准并实时地获取电压源逆变器(voltage sourceinverter,VSI)输出的三相电流信息是保证控制系统可靠性的重要前提[1-4]㊂传统电流采集是将多个传感器安放在逆变器输出侧和直流母线侧以得到三相电流值并对直流母线形成过电流保护㊂但多个传感器会因其参数不一致对控制精确度产生影响,同时增加系统重量㊁体积及费用㊂单电流传感器(single current sensor,SCS)相电流重构技术能够有效避免上述问题,近年来被广泛研究㊂SCS相电流重构技术利用安装在直流母线侧的单个电流传感器,通过多时刻动态采集直流信息,并依照与三相电流映射关系,实现相电流重构㊂然而,控制系统中的电压基准芯片㊁电流传感器㊁运算放大器等装置存在零点漂移现象,将导致电流采样出现误差,并因误差扩大效应而影响电流重构精确度㊂精确的相电流测量对电机控制系统来说至关重要,文献[5]分析了电流测量误差对电流控制器中相电流和输出电压的影响,提出了一种误差补偿策略,在不需要额外的硬件设备基础上利用电流控制器的基准电压对偏置和缩放误差分别进行补偿㊂该技术需要至少两个电流传感器来获取三相电流信息,多传感器的不一致性会影响采样精确度㊂文献[6]根据直流输出电压纹波特性结合带通和低通滤波器来估计直流偏移和缩放误差,提出一种电流测量误差补偿方案,能够有效地抑制电压和电流测量误差的影响㊂然而,该方法无法确定控制系统中故障传感器的具体安装位置㊂针对单传感器相电流重构方法,文献[7]基于修改逆变器开关状态,在过调制区域完成相电流重构,改变后的开关脉冲不再保持对称,相电流发生较大畸变㊂接着,文献[8]分析了实测相电流与重构相电流之间重构误差产生的各类原因并提出相应解决方案,但无法对直流电流偏置误差实时计算㊂文献[9]使用检测电压注入法,通过将两个相对的有效矢量组合,插入空间矢量脉冲宽度调制(space vector pulse width modulation, SVPWM)脉冲用以检测和消除直流母线电流传感器的偏置误差㊂文献[10]提出了一种新型SCS算法(测量矢量插入法)用于重构相电流,该算法使用有源电压矢量克服了不可观测盲区问题,同时对机器性能和运行范围的影响最小㊂接着,文献[11]将测量矢量插入算法整合到闭环电流调节器中,该调节器将虚拟有源电阻状态反馈引入同步坐标系电流调节器中,消除了因测量矢量对控制器引起的干扰㊂文献[9-11]所提方法引入额外的开关动作,增加开关损耗㊂文献[12]提出了一种零电压矢量采样方法,可以在不修改PWM信号的情况下将低调制区域和扇区边界区域中的电流重构盲区移向空间矢量六边形的边界,避免了复杂的算法和开关次数的增加,有利于永磁同步电机的驱动性能㊂在此基础上,文献[13]采用零电压矢量采样法来实现对中小功率电压源逆变器开路故障诊断,重构的三相电流用于生成可以检测和定位开关故障的诊断变量㊂文献[14]讨论了多个采样位置的优化选择,以降低所提SCS耦合多个可用位置策略的实际实施难度㊂文献[12-14]中所提出的相电流重构方法无法利用分流电阻获取电流信息,且增加了被测支路间电流信号的干扰㊂本文阐明直流母线单电流传感器相电流重构原理,对比多电流传感器与单电流传感器零点漂移误差,揭示零点漂移误差产生的原因及扩大效应的产生机理,基于插入互补有效电压矢量代替零矢量的空间矢量脉冲宽度调制方法,提出零点漂移误差自校正策略㊂分析各扇区电流观测窗口时长,利用互补有效电压矢量动态电流双采样,实现相电流重构与电流零点漂移量的自检测和自校正㊂在搭建的控制系统实验平台上验证所提误差自校正策略能为控制系统提供可靠的重构电流㊂1㊀单电流传感器误差扩大效应1.1㊀直流母线SCS采样基本原理定义实现电流信息准确采集所需最短时长为最小采样时间T min,其大小主要由硬件电路性能决定,如图1所示㊂图中:t d表示死区时间;t on表示功率开关器件延迟导通时间;t r表示上升时间;t A/D表示数模转换时间;t sr表示振荡时间;t stable表示电流稳定时431电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第27卷㊀间[15]㊂T min 可表示为T min =t d +t on +t r +t sr +t A /D ㊂(1)图1㊀理想与实测电流脉冲波形Fig.1㊀Ideal and actual current pulse waveforms三相两电平VSI 驱动系统如图2所示㊂同相桥臂高低两个开关导通状态以Q x (x =a,b,c)表示㊂高开关管导通,低开关管关断,以Q x =1表示;反之,以Q x =0表示㊂如图3所示,用V i =(Q a ,Q b ,Q c )代表电压空间矢量8类开关组合状态(i =0,1,2,3,4,5,6,7)㊂图3为基本电压矢量合成调制区域,定义不可观测区域包含扇区边界和低调制区域㊂在SVPWM 策略下,当参考电压矢量V ref 位于不可观测区域时,有效电压矢量作用时长小于T min ,导致采样不准确㊂图2㊀VSI 驱动系统拓扑Fig.2㊀VSI drive systemtopology图3㊀基本电压矢量合成调制区域Fig.3㊀Basic voltage vector synthesis modulation regionVSI 负载相电流i a ㊁i b 和i c 与直流母线电流i dc 之间的关系如表1所示㊂在单个SVPWM 调制周期内对直流母线电流进行两次采样,若有效电压矢量的作用时间大于T min ,则其对应电流i dc 能够被精确获取,依照表1即可得到对应两相电流值㊂根据基尔霍夫电流定律可计算出余相电流值,即i a +i b +i c =0㊂(2)表1㊀直流母线电流与开关状态关系Table 1㊀Relationship between DC bus current andswitch state开关状态100101001011010110000111母线电流+i a-i b+i c-i a+i b-i c以Ⅰ扇区为例,SVPWM 直流母线SCS 采样原理如图4所示㊂图中上半部分表示三相SVPWM 脉冲,下半部分为对应直流母线电流,两个有效电压矢量V 1(100)和V 2(110)分别对应电流观测窗口时长T spl1和T spl2㊂当T spl1和T spl2同时大于T min 时,通过对电流i dc 的采样可得到两相电流信息i a 和-i c ,进而依照式(2)重构出三相电流㊂然而,在不可观测区域,V 1和V 2至少有一个会因其作用时间过短而导致对应电流观测窗口时长小于T min ,此时电流i dc 不能够被准确地采集,致使相电流重构误差变大㊂图4㊀SVPWM 直流母线SCS 采样原理(Ⅰ扇区)Fig.4㊀SVPWM DC bus SCS sampling principle (sectorⅠ)1.2㊀误差的分析及其扩大效应直流母线采样零点漂移误差主要由霍尔效应电流传感器㊁运算放大器造成的零点漂移和电压基准芯片造成的电压基准漂移组成㊂受环境温度㊁封装应力㊁内部元件参数不一致等因素的影响,霍尔效应531第7期申永鹏等:直流母线单电流传感器零点漂移误差自校正策略电流传感器㊁运算放大器和电压基准芯片存在零点漂移现象,输出信号将偏离理论值㊂令VSI 负载三相电流由I a ㊁I b 和I c 表示,未发生零点漂移前直流母线电流值为I dc_m ,零点漂移造成的电流漂移量用I e 表示㊂以A 相电流为例,基本电压矢量(100)和(011)分别对应电流值为i a 和-i a ,利用直流母线SCS 完成相电流重构时,A 相实际电流值分别为I a1或I a2,若I a >0,则:I a =I a1=I dc_m +I e (100);Ia2=-(-I dc_m +I e )(011)㊂{(3)由上式得I a1-I a2=2I dc_m ,即实际测量计算后误差将扩大至2I e ㊂当I a <0时,误差同样为2I e ,将此现象称之为误差扩大效应㊂SCS 误差扩大效应如图5所示,γ为电流噪声,与多电流传感器零点漂移误差相比,利用SCS 实现相电流重构时,零点漂移产生的误差是前者的2倍㊂图5㊀SCS 电机控制系统误差扩大效应Fig.5㊀Error expansion effect of SCS motor control system2㊀零点漂移误差自校正策略2.1㊀误差自校正SVPWM 发波方法在整个空间矢量平面的扇区边界和低调制区域(自校正区域)使用主动零状态脉冲宽度调制方法(active zero space vector pulse width modulation,AZS-VPWM),剩余区域使用SVPWM 方法,AZSVPWM 利用两个相邻有效电压矢量和两个具有相同作用时间的互补有效电压矢量来合成参考电压矢量V ref ㊂如图6所示,以Ⅰ扇区为例,在自校正区域内,传统SVPWM 开关顺序中的V 0和V 7被互补有效电压矢量V 3和V 6代替㊂该过程中零矢量作用时间T 0被平均分配到两个互补矢量,即T 0/2=T 3=T 6,T x 为矢量作用时长(x =3,6),则零电压矢量为V 0T 0=V 3T 02+V 6T 02㊂(4)图6㊀AZSVPWM 参考电压矢量合成原理(Ⅰ扇区)Fig.6㊀AZSVPWM reference voltage vector synthesisprinciple (sector Ⅰ)由伏秒平衡理论得参考电压矢量V ref 可由4个基本电压矢量合成,即V ref (cos θ+jsin θ)T s =V 1T 1+V 2T 2+V 3T 3+V 6T 6㊂(5)其中:θ表示V ref 在空间矢量平面的旋转角度;T s 表示调制系统的载波周期㊂AZSVPWM 各基本电压矢量的合成时段可表示为:T 1=23πT s M [sin(π3+θ)-sin(θ)];T 2=2πT s M [3sin(π6+θ)-3sin(π3+θ)];T 3=T 6=T s 2-3πT s M sin(π3+θ);M =πV ref 2U dc ㊂üþýïïïïïïïïïï(6)其中M 表示调制度㊂参考电压矢量V ref 位于Ⅱ~Ⅵ扇区时,θ须减去(N -1)π/3,N 为扇区序号(N =1,2,3,4,5,6)㊂该方法在整个空间矢量平面是线性的,开关顺序如表2所示,可见插入互补有效电压矢量作用效果与零矢量相同㊂通过搭建MATLAB /Simulink 仿真模型,得到SVPWM 和AZSVPWM 两种方法下电流观测窗口(T pl1㊁T pl2和T pl3㊁T pl4)随扇区变化曲线如图7所示㊂631电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第27卷㊀图7(a)为各扇区切换时刻,对应图7(b)中T pl1或T pl2在扇区边界处小于T min ㊂利用互补有效电压矢量替代零矢量后,得到电流观测窗口T pl3和T pl4如图7(c)所示,在整个空间矢量平面内,T pl3和T pl4均大于T min ,满足了一个SVPWM 周期内重构和校正3次电流采样运行和处理时间所需要求㊂表2㊀AZSVPWM 各扇区开关动作顺序Table 2㊀AZSVPWM switching sequence of each sector模式开关顺序Ⅰ6123-3216Ⅱ4321-1234Ⅲ2345-5432Ⅳ6543-3456Ⅴ5461-1645Ⅵ2165-5612图7㊀扇区对应电流观测窗口时长Fig.7㊀Duration of current observation window以扇区I 为例,图8描述了AZSVPWM 技术的开关脉冲产生过程㊂当V ref 处于不可观测区域时,根据AZSVPWM 和SVPWM 中开关脉冲占空比的相互关系,可以得到开关动作时间,如表3所示㊂K Mq x 和K Sq x (x =1,2,3)分别表示AZSVPWM 和SVPWM 中各功率开关器件动作时间㊂之后根据表4给动作寄存器赋值,完成整个开关脉冲的产生过程㊂P CLC /P SET ㊁U CLC /U SET 和D CLC /D SET 分别表示当计数器等于周期值㊁比较值A 和比较值B 时,输出低(或高)电平㊂整个过程中开关脉冲电流采样窗口时长相对延长,保证电流被精确采集,同时通过调整开关脉冲占空比的大小对输出电流进行实时控制㊂图8㊀AZSVPWM 技术下开关脉冲产生过程Fig.8㊀Process of switching pulse generation underAZSVPWM technology图8中:epx.A 为比较寄存器A (counter-com-pare A,CMP)的值,x =1,2,3;K Sq x /K Mq x 为动作时间,x =1,2,3㊂表3㊀AZSVPWM 各扇区开关动作时间变换过程Table 3㊀AZSVPWM each sector switching action schedule扇区开关动作时间变换算法I &IV K Mq1=K Sq3K Mq2=K Sq2K Mq3=K Sq1II &V K Mq1=K Sq1K Mq2=K Sq3K Mq3=K Sq2III &VIK Mq1=K Sq2K Mq2=K Sq1K Mq3=K Sq3互补矢量插入后AZSVPWM 脉冲及其采样电流如图9所示(以Ⅵ扇区和I 扇区边界为例),其中i ec1和i ec2为自校正电流,i rc1和i rc2为重构电流㊂在一个AZSVPWM 周期进行重构和校正3次电流采样,每个扇区自校正区域使用的有效电压矢量和对应自校正电流如表5所示,在自校正过程中可以得到3个电流值㊂AZSVPWM 和SVPWM 两种调制方式之间能够平稳渡,不存在脉冲错位现象,尽可能地减少因731第7期申永鹏等:直流母线单电流传感器零点漂移误差自校正策略互补矢量插入所引起的相电流总谐波失真的增加㊂表4㊀AZSVPWM 动作寄存器设定方式Table 4㊀AZSVPWM action register assignment扇区动作寄存器赋值I 和IVP SET -D CLC -U SETP CLC -D SET -U CLC P SET -D CLC -U SET II 和VP CLC -D SET -U CLC P SET -D CLC -U SET P SET -D CLC -U SET III 和VIP SET -D CLC -U SET P SET -D CLC -U SET P CLC -D SET -UCLC 图9㊀AZSVPWM 开关脉冲和采样时刻(I 扇区)Fig.9㊀AZSVPWM switching pulse and samplingtime (sector I )表5㊀各扇区有效矢量及测量电流Table 5㊀Effective vector and measured currentper sector扇区有效矢量测量电流重构电流自校正电流ⅠV 1㊁V 2㊁V 3㊁V 6前:+i a ㊁-i b +i b ㊁-i b 后:-i b ㊁-i c +i b ㊁-i b ⅡV 1㊁V 2㊁V 3㊁V 4前:+i a ㊁-i c+i a ㊁-i a 后:-i a ㊁+i b +i a ㊁-i a ⅢV 2㊁V 3㊁V 4㊁V 5前:+i b ㊁-i c +i c ㊁-i c 后:+i c ㊁-i a+i c ㊁-i cⅣV 3㊁V 4㊁V 5㊁V 6前:-i a ㊁+i b +i b ㊁-i b 后:-i b ㊁+i c +i b ㊁-i b ⅤV 1㊁V 4㊁V 5㊁V 6前:+i c ㊁-i a+i a ㊁-i a 后:+i a ㊁-i b +i a ㊁-i a ⅥV 1㊁V 2㊁V 5㊁V 6前:+i c ㊁-i b +i c ㊁-i c 后:+i a ㊁-i c+i c ㊁-i c 2.2㊀自校正策略本文采用AZSVPWM 方法对直流母线零点漂移产生的误差进行校正,在一个载波周期内,对插入的互补电压矢量进行采样,得到采样电流I 1和I 2㊂则:I 1=I dc_m +I e ;I 2=-I dc_m +I e ㊂}(7)实际电路中,由于零点漂移的存在,由式(7)可得I 1+I 2=2I e ㊂(8)根据式(8)可得到漂移量I e ,进而计算出校正后的相电流电流I c1㊁I c2为:I c1=I 1-I e ;I c2=I 2-I e ㊂}(9)AZSVPWM 自校正策略通过在一个SVPWM 载波周期内对插入互补电压矢量进行双重采样,实现了漂移量I e 的检测,从而完成了重构电流自校正㊂校正后的实际电流和重构电流如图10所示,由于3次电流采样不同步以及A /D 转换时间的存在,重构相电流与实际电流将产生θ角的相位误差㊂图10㊀AZSVPWM 自校正策略下实际与重构电流误差情况Fig.10㊀Actual and reconstructed current error underAZSVPWM self-correction strategy3㊀实验验证整个电驱动控制系统原理如图11所示㊂对应实验平台如图12所示,控制芯片采用德州仪器公司的TMS320F28035型DSP,载波频率恒定在10kHz,使用型号为MODVK48T17D200K 的三相感应电机作为系统驱动电机,其参数如表6所示㊂使用力科公司型号为MDA805A 的电驱动分析仪来完成实验数据的采集与分析㊂根据实验平台硬件设备计算最小采样时间T min =6.33μs,其中:t dead =2.00μs,t A /D =3.33μs,t on +t rise +t sr =1.00μs㊂831电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第27卷㊀图11㊀AZSVPWM 电驱动控制系统原理Fig.11㊀Principle of AZSVPWM electric drive controlsystem图12㊀电驱动控制实验平台Fig.12㊀Electric drive control experiment platform表6㊀系统驱动电机参数Table 6㊀System drive motor parameters㊀㊀㊀参数数值额定功率P /W 184额定频率f /Hz 60额定电压U /V 208-230/460额定转速n /(r /min)1721各扇区PWM 信号㊁采样脉冲和直流母线电流波形如图13所示,可以看出所提AZSVPWM 自校正策略利用非零互补有效电压矢量替代零矢量消除了不可观测区域,且采样脉冲跟随SVPWM 波形占空比的变化实时调整触发沿位置,各采样时刻均大于T min ,对应母线电流平稳,保证了采样准确进行㊂在起动过程中,电机实测和重构三相电流曲线如图14所示㊂初始阶段实测相电流值为零,但由于零点漂移现象的存在,未校正时重构相电流值不为零且在漂移量附近波动㊂起动阶段存在过电流现象,当M =0.6电机平稳运行在转速1721r /min 时,实测相电流和重构相电流如图15所示㊂图13㊀误差自校正区域各扇区开关脉冲及对应采样时刻Fig.13㊀Switching pulses of each sector in error self-correction area and corresponding sampling time931第7期申永鹏等:直流母线单电流传感器零点漂移误差自校正策略图14㊀电机起动过程实测和重构相电流曲线Fig.14㊀Measured and reconstructed phase current curves during motorstarting图15㊀AZSVPWM 实测和重构相电流(M =0.6,1721r /min )Fig.15㊀AZSVPWM measured and reconstructed phasecurrent (M =0.6,1721r /min )令实测相电流为i x _ac ,重构相电流为i x _rc (x =a,b,c)㊂在整个电机运行矢量平面内,电流能够平稳过渡且在不可观测区域相电流能够准确重构㊂因分时采样和重构算法运行依照时间顺序进行,导致实测和重构相电流波形之间存在相位差㊂实测与重构电流之间的重构误差e 可由下式计算:e =i x _ac -i x _rci x _acˑ100%㊂(10)以A 相为例,图16和图17分别展现了误差自校正前后重构相电流㊁实测相电流及其重构误差曲线,由式(10)计算得出校正后的最大重构误差由校正前的4.17%下降为3.42%㊂图18为低速低调制度(120r /min,M =0.3)下AZSVPWM 方法重构和实测电流波形,此时重构电流仍保持良好的正弦曲线,能够为控制系统提供可靠的电流信号㊂该工况下重构误差曲线如图19所示,校正后重构误差小于3.56%㊂在工频50Hz 供电环境下,所提误差自校正策略得出实测和重构相电流波形如图20所示,对应误差曲线如图21所示,可以看出在该工况下实测和重构相电流曲线保持良好的正弦状态,且重构误差低于3.51%,整个控制系统运行稳定㊂图16㊀A 相实测和重构相电流波形及其误差曲线(无校正)Fig.16㊀Phase A measured and reconstructed phasecurrent waveform and its error curve (with-out correction)图17㊀A 相实测和重构相电流波形及其误差曲线(有校正)Fig.17㊀Phase A measured and reconstructed phasecurrent waveform and its error curve (with correction)图18㊀AZSVPWM 实测和重构相电流(M =0.3,120r /min )Fig.18㊀Measured and reconstructed phase current ofAZSVPWM (M =0.3,120r /min )41电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第27卷㊀图19㊀低速下A 相电流误差曲线Fig.19㊀Phase A current error curve at lowspeed图20㊀工频50Hz 下实测和重构相电流(M =0.6,1500r /min )Fig.20㊀Measured and reconstructed phase current atpower frequency 50Hz (M =0.6,1500r /min)图21㊀工频50Hz 下实测和重构相电流误差曲线Fig.21㊀Measured and reconstructed phase current er-ror curve at power frequency 50Hz图22和图23分别验证了在动态工况下,所提AZSVPWM 方法重构相电流的准确性㊂电机加减速过程中,重构电流能够实时跟随实测电流平稳变化㊂加速时A 相电流重构误差曲线如图24所示,重构误差控制在3.31%以内㊂验证了所提AZSVPWM 方法在动态环境下的稳定性㊂当调制度M 由0.7变为0.25时,对应实测和重构相电流如图25所示,瞬时变换时刻电流发生畸变,之后能够快速恢复平稳㊂以上过程验证了AZS-VPWM 方法在动态工况下能够对电机进行实时控制,保证了整个控制系统的可靠性和稳定性㊂图22㊀加速过程中AZSVPWM 方法实测和重构相电流Fig.22㊀AZSVPWM method measures and reconstructsphase current duringacceleration图23㊀减速过程中AZSVPWM 方法实测和重构相电流Fig.23㊀AZSVPWM method measures and reconstructsphase current duringdeceleration图24㊀AZSVPWM 加速过程中A 相重构误差曲线Fig.24㊀A-phase reconstruction error curve during AZSVPWMacceleration图25㊀调制度突变时实测和重构相电流Fig.25㊀Measurement and reconstruction of the phasecurrent when the modulation degree changes suddenly4㊀结㊀论针对直流母线单传感器零点漂移误差问题,本141第7期申永鹏等:直流母线单电流传感器零点漂移误差自校正策略文揭示了零点漂移误差产生的原因及其扩大效应,基于插入互补有效电压矢量代替零矢量的SVPWM 调制方法,提出了零点漂移误差自校正策略,利用互补有效电压矢量动态电流双采样,实现了电流零点漂移量的自检测和自校正㊂其主要效果如下:1)AZSVPWM产生的SVPWM波在调制周期内相互对称,继承了SVPWM优越的动静态特性; 2)所提误差自校正策略减弱了零点漂移对电流重构精确度的影响,降低了重构误差㊂额定转速下(1721r/min,M=0.6)相电流重构误差由原来的4.17%降低至3.42%,低速下(120r/min,M=0.3)相电流重构误差小于3.56%㊂参考文献:[1]㊀王旭东,杨传江.逆变器故障容错控制策略研究[J].电机与控制学报,2020,24(11):37.WANG Xudong,YANG Chuanjiang.Tolerant control strategy for inverter faults[J].Electric Machines and Control,2020,24(11):37.[2]㊀刘和平,董治平,邱彬彬,等.一种低压电动汽车用逆变器非线性因素的新型补偿方法[J].电机与控制学报,2020,24(9):30.LIU Heping,DONG Zhiping,QIU Binbin,et pensation method for nonlinear factors of inverter for low voltage electric vehi-cle[J].Electric Machines and Control,2020,24(9):30. [3]㊀陈虹,赵明星,赵海艳,等.三相逆变器的随机双PID组合优化方法[J].电机与控制学报,2018,22(10):1.CHEN Hong,ZHAO Mingxing,ZHAO Haiyan,et binato-rial optimization control strategy for a three-phase inverter with ran-dom double PID[J].Electric Machines and Control,2018,22(10):1.[4]㊀黄辉先,韩建超,刘湘宁,等.逆变器驱动电机系统共模电压抑制模型预测控制[J].电机与控制学报,2018,22(9):84.HUANG Huixian,HAN Jianchao,LIU Xiangning,et al.Model predictive control to suppress common mode voltage of inverter drive motor system[J].Electric Machines and Control,2018,22(9):84.[5]㊀KIM M,SUL S K,LEE pensation of current measurementerror for current-controlled PMSM drives[J].IEEE Transactions on Industry Applications,2014,50(5):3365.[6]㊀TRINH Q N,WANG P,TANG Y,et pensation of DC off-set and scaling errors in voltage and current measurements of three-phase AC/DC converters[J].IEEE Transactions on Power Elec-tronics,2017,33(6):5401.[7]㊀马鸿雁,孙凯,魏庆,等.变频调速系统过调制时的相电流重构方法[J].清华大学学报,2010,50(11):1757.MA Hongyan,SUN Kai,WEI Qing,et al.Phase current recon-struction for AC motor adjustable-speed drives in the over-modula-tion method[J].Journal of Tsinghua University,2010,50(11):1757.[8]㊀马鸿雁,孙凯,魏庆,等.PWM逆变器相电流重构研究与误差分析[J].电工技术学报,2011,26(1):108.MA Hongyan,SUN Kai,WEI Qing,et al.Phase current recon-struction method for PWM inverter and error analysis[J].Electric Machines and Control,2011,26(1):108.[9]㊀LU J,HU Y,CHEN G,et al.Mutual calibration of multiple cur-rent sensors with accuracy uncertainties in IPMSM drives for elec-tric vehicles[J].IEEE Transactions on Industrial Electronics, 2019,67(1):69.[10]㊀KIM H,JAHNS T M.Phase current reconstruction for AC motordrives using a DC link single current sensor and measurementvoltage vectors[J].IEEE Transactions on Power Electronics.2006,21(5):1413.[11]㊀KIM H,JAHNS T M.Current control for AC motor drives using asingle DC-link current sensor and measurement voltage vectors[J].IEEE Transactions on Industry Applications,2006,42(6):1539.[12]㊀XU Y,YAN H,ZOU J,et al.Zero voltage vector samplingmethod for PMSM three-phase current reconstruction using singlecurrent sensor[J].IEEE Transactions on Power Electronics,2016,32(5):3797.[13]㊀YAN H,XU Y,ZOU J,et al.A novel open-circuit fault diagno-sis method for voltage source inverters with a single current sensor[J].IEEE Transactions on Power Electronics,2018,33(10):8775.[14]㊀TANG Q,SHEN A,LI W,et al.Multiple-positions-coupledsampling method for PMSM three-phase current reconstructionwith a single current sensor[J].IEEE Transactions on Power E-lectronics,2019,35(1):699.[15]㊀SHEN Y,ZHENG Z,WANG Q,et al.DC bus current sensedspace vector pulse width modulation for three-phase inverter[J].IEEE Transactions on Transportation Electrification,2020,7(2):815.(编辑:刘素菊)241电㊀机㊀与㊀控㊀制㊀学㊀报㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀㊀第27卷㊀。
冰储热控制装置[发明专利]
![冰储热控制装置[发明专利]](https://img.taocdn.com/s3/m/d6317dfac281e53a5902ff4d.png)
专利名称：冰储热控制装置
专利类型：发明专利
发明人：威廉·T·奥斯本,加里·D·史密斯申请号：CN01121224.1
申请日：20010606
公开号：CN1332349A
公开日：
20020123
专利内容由知识产权出版社提供
摘要：一种测量冰储热系统中的结冰量的装置,该系统具有一带储液的储箱和装在其中的冷却盘管组件。
还有一种测量结冰量的方法,它所用的装置包括对盘管组件提供向上升力的装置,测量储箱中盘管垂直位移的装置和使冷却盘管组件上结冰量与冷却盘管组件的垂直位移发生关系的装置,还提出了用在这种储箱中的特殊的向上升力的组件。
申请人：巴尔的摩汽圈公司
地址：美国马里兰
国籍：US
代理机构：中国国际贸易促进委员会专利商标事务所
代理人：张金熹
更多信息请下载全文后查看。
破冰机 英文专业术语
破冰机英文专业术语The Ice-Breaking MachineIn the realm of maritime operations, the ice-breaking machine plays a crucial role in navigating through frozen waterways. These specialized vessels are designed to plow through thick layers of ice, creating pathways for other ships to follow. The ice-breaking machine's ability to overcome the formidable obstacles posed by frozen waters has been a game-changer in the world of maritime transportation and exploration.At the heart of an ice-breaking machine lies a powerful engine that drives a unique hull design. The hull's shape, often featuring a reinforced bow and a rounded bottom, allows the vessel to ride up and over the ice, breaking it into manageable chunks. This process is known as "icebreaking," and the machine's efficiency in this regard is measured by its "icebreaking capacity," which refers to the maximum thickness of ice the vessel can successfully navigate through.One of the key components of an ice-breaking machine is the "icebreaker bow," a reinforced and angled section of the hull that is designed to split and push aside the ice as the vessel advances. Theicebreaker bow is often equipped with specialized features, such as "ice knives" or "ice cleats," which help to further fracture the ice and improve the machine's overall icebreaking performance.Another crucial aspect of an ice-breaking machine is its "propulsion system," which provides the necessary power to propel the vessel through the ice. This system typically consists of a combination of diesel engines, electric motors, and specialized propellers or waterjets. The propulsion system's efficiency is crucial in determining the machine's "icebreaking speed," which is the rate at which it can navigate through the ice.In addition to its icebreaking capabilities, the ice-breaking machine is also designed to provide a safe and comfortable environment for its crew. The vessel's "bridge" or "control room" is outfitted with advanced navigational equipment, such as "radar systems," "sonar devices," and "GPS navigation," which allow the crew to monitor the surrounding ice conditions and plan their route accordingly.To ensure the safety and well-being of the crew, ice-breaking machines are also equipped with various "safety features," such as "emergency escape hatches," "life rafts," and "survival suits." These features are crucial in the event of an unexpected incident or emergency, as the crew may need to rapidly evacuate the vessel or withstand harsh environmental conditions.The development and operation of ice-breaking machines require a high level of "engineering expertise" and "technological innovation." Engineers and researchers are constantly working to improve the machines' performance, efficiency, and safety, incorporating the latest advancements in materials science, hydrodynamics, and propulsion technology.Moreover, the use of ice-breaking machines is not limited to maritime transportation; these vessels also play a vital role in various other applications, such as "scientific research," "oil and gas exploration," and "rescue operations." In these scenarios, the ice-breaking machine's ability to access and navigate through frozen environments is crucial for the success of these missions.In conclusion, the ice-breaking machine is a remarkable feat of engineering, designed to overcome the challenges posed by frozen waterways. Its ability to plow through thick layers of ice, create pathways for other vessels, and provide a safe and comfortable environment for its crew has made it an indispensable tool in the world of maritime operations and beyond. As technology continues to advance, the role of the ice-breaking machine is only expected to grow in importance, ensuring the continued exploration and utilization of the Earth's frozen frontiers.。
杰弗逊扇机用于潜水和潜水活动的产品说明书
Figure 1. Split Taper Bushing with Hub
DO ቤተ መጻሕፍቲ ባይዱOT LUBRICATE CAPSCREWS, BORE, OR BUSHING BARREL
Table 1. Capscrew Torque Values - Split Taper Bushings
BUSHING NO. H P-1 P-2 Q-1 Q-2 R-1 R-2
WARNING
Do not attempt to pull the bushing flange flush with the hub end. There should be 1/8" to 1/4" clearance when tightened.
clamping fit. The torque must not exceed that shown in Table 1. (Note: this is not a locating dimension.) 2. Instructions for removing impeller assembly from the shaft: a. Remove all capscrews from the impeller and hub assembly. b. Start capscrews into the threaded holes in the bushing flange. c. Tighten each bolt successively part of a turn to force the impeller off the bushing. This forces the bushing loose from the impeller and releases the compression so that the entire assembly will slide from the shaft. d. Pull the bushing off the shaft. If the assembly has been in place some time, it may be necessary to use a wheel puller to remove the bushing. Never use a wheel puller on the impeller.
阿尔法冷系列Laing DDC-Pump 12V DDC-1T 4.1冷水循环泵说明书
This pump is the first pump worldwide which is used in mass-produced water cooled workstations and is ideal for the watercoolingof processors and electronic components. Due to its compact size andits power it can be used for many applications. •Ball motor pump with spherically shaped rotor/impeller unit •Fits easily into all commercially available PC, barebone and mini-PC cases•Enables efficient operation with relatively highperformance1x Laing DDC-Pump 12V DDC-1T 4.1, black V. 1.001 // 12.2022Laing DDC-Pump 12V DDC-1T 4.1Alphacool article number: 6500023This pump is the first pump worldwide which is used in mass-produced water cooled workstations and is ideal for the watercooling of processors and electronic components. Due to its compact size and its power it can be used for many applications.This DC pump is an electronically commuted ball motor pump with an estimated lifespan of more than 50.000hrs at 12V. The only moving part on the pump is the spherically shaped Rotor unit which is sitting on an ultra-hard, wear-resistant ceramics bearing ball.A conventional shaft with bearings and seals is not used or needed. The spherical bearing of the rotor unit on the ceramics bearing ball has many advantages: The development of bearing clearance is technically impossible which results in the impossibility of noise level increase over the lifespan of the pump. The bearing is self-adjusting, making the pump consistently quiet in operation over the full lifespan. The pump is directly lubricated by the coolant (wet-running pump). Therefore no maintenance is required.As the rotor is magnetically held in place even small dirt particles pose no problem for the mechanism, a blocking of the pump is not possible under normal operating conditions. Even after a long period of standstill reliable operation is ensured. The permanent magnetic rotor unit is frictionlessly driven by a magnetic field which is produced by the surrounding stator.The stator is completely built around the rotor, therefore the pump is only slightly higher than the stator unit. It therefore fits a in almost any PC case, may it be Super tower or Barebone. A separate magnetic shielding is usually not required. The ball motor principle allows powerful yet power-saving operation. The pump can be regulated by power variations of the DC operating voltage over a wide range. All parts in touch with the coolant are completely corrosion free.Pump tacho: With 3-pin Molex connector as pump tacho output (for mainboards or control units)Why are there Swiftech and Laing Versions? Are they different?The latter question can be answered quickly: No! H ere an explanation: Lain produces all pumps in H ungary. They are just labelled differently for Overseas markets and the European market. The pumps themselves are threfore exactly identical. The overseas version has Swiftech as a distributor and the European version is neutrally black. The cheaper Swiftech pumps are usually shipped with decouplers, the Laing pumps usually not. The power, pressure head, flow rates, etc. are exactly the same.Important: The pump is the latest revision. We recommend the use of lubricating water additive (such as AT Protect Plus or Innovatek Protect). Anti-Corro-Fluid is not recommended. The Laing pump's electronics are not waterproof. Please make sure that the electronic components do not come in contact with water during installation or when working on the pump. When replacing the top always ensure a proper fit of the O-ring seal and avoid spills when filling the Laing reservoir. Damages due to water in the electronic components are not replaced by Laing! Due to the power of the pump, itDrawing。
制冰冷却系统减轻电网压力
制冰冷却系统减轻电网压力
大卫·理查德森
【期刊名称】《科技创业》
【年(卷),期】2010(000)007
【摘要】在接下来的几个星期里，加利福尼亚的地方公共事业联盟将开始为政府办公室和商业大楼加装夜间制冰系统以代替白天时使用空调。
这是该设备试点项目的一部分，此设备由总部设在哥伦比亚温莎的Ice Energy建造。
【总页数】1页(P69)
【作者】大卫·理查德森
【作者单位】
【正文语种】中文
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2.自制冰袋冷敷减轻甲状腺结节微波消融术后疼痛的效果观察
3.天然气管网压力能发电制冰技术的开发及应用
4.天然气压力能发电制冰一体化应用设计与经济性分析
5.关注教师职业压力——减轻教师职业压力提升教师职业幸福感
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TI:打造更安全、更环保、更智能的电机驱动器
TI：打造更安全、更环保、更智能的电机驱动器
韩霜
【期刊名称】《世界电子元器件》
【年(卷),期】2014(0)9
【摘要】日前,德州仪器（TI）在北京举办了工业应用研讨会,展示了一系列最新的工业应用半导体技术以及最前沿的解决方案,并结合丰富全面的应用实例与技术介绍,供与会嘉宾体验最新的技术与创新。
除北京外,此次TI工业应用研讨会业已于8月21日、8月26日分别在深圳和上海举行。
在研讨会期间,TI公司还向参加研讨会的媒体重点介绍了公司的电机驱动器产品。
【总页数】2页(P44-45)
【作者】韩霜
【作者单位】
【正文语种】中文
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3.更安全、更环保、更舒适、更经济的驾乘体验 [J], 陈永光
4.智能解决方案让汽车更节能、更环保、更亮丽——深入走访巴斯夫，感受其超凡的汽车技术及应用能力 [J], 陈永光
5.扎根电机市场 TI会一直走下去致力于更智能·更安全·更绿色环保 [J], 陈颖莹
因版权原因，仅展示原文概要，查看原文内容请购买。