液压支架外文翻译

外文资料翻译
学生姓名： xxx 专业班级： xxx 指导教师：xxx
内蒙古科技大学机械工程学院
2013年6月
对煤矿开采中液压支架电液控制系统的研究Research on electro-hydraulic control system for hydraulic support
at coal mine
学生姓名：xxx
学号：xxx
专业：xxx
班级：xxx
学院（系）：xxx
指导教师：xxx
对煤矿开采中液压支架电液控制系统的研究
摘要基于国内外全面综采工作面情况的分析和调查，提出、设计、实现液压支架电液控制系统的新要求。

它采用本质安全电路的设计技术和现场总线技术以连接到主机的所有控制单元。

每个控制单元的控制系统是配备一个液压支架。

由其他控制单元或主机所控制的某些控制单元能够提供相邻支撑、远程支撑和一组的支持。

在防爆外壳的电脑主机也有的实时监控，远程控制，故障诊断和上传数据等功能。

三个月的工业性试验的结果表明，该系统工作可靠，达到了设计要求。

关键字液压支架；电液控制系统；主机
1.引言
电液控制系统是液压支架完全机械化采煤工作面的的核心，可以实现自动控制生产,提高生产效率、工作条件和采煤工作面的安全。

基于网络的系统检测采煤机的位置，实现液压支架自动控制。

此外，它有能力监控其他设备，实现地面和地下的计算机之间的通信，完成远程控制。

与其他电液控制系统相比，它具有显著的优点，如抗高压，防燃防爆，防尘，防腐蚀，抗震动，抗电磁干扰。

国外自70年代中期人们已经开始研究液压支架电液控制系统，九十年代经过近十年推出产品并逐步完善。

目前，许多国家在推广阶段已经有了不同特点的成熟的产品，如德国、美国、英国、波兰、日本、法国和俄罗斯等。

目前，在中国生产的液压支架的控制方式以手工操作为主，这相当于发达国家在1970年的控制水平。

配备了电液控制系统液压支架生产于国外，特别是在德国。

那些已经进入国内市场的优秀的企业主要是德国的德伯特（DBT，它的总部是在美国比塞洛斯），玛克（Marco），EEP和TIEFENBACH和美国的JOY公司。

尽管我们的政府从九十年代起已经投入了大量资金支持液压支架电液控制系统的技术研究，但我们还没有实现系统的产业化和本土化的目标。

为了提高采矿设备的水平，增强的际竞争力，打破国际技术垄断，就必须研究和自主生产液压支架的电液控制系统。

2.电液压控制系统的结构
通过对由德国的EEP公司、玛克（Marco）公司所生产液压支架的电液控制系统的结构分析，结合实际应用程序，提出了自行设计的电液压控制系统的方框图如图1。

图1 自行设计的电液压控制系统的方框图
液压支架电液控制系统主要包括控制单元，主机和本质安全的网络。

辅助控制单元包括控制器，传感器，电磁导阀和主控制阀。

该控制单元由主缆相互连接的。

控制器采用自定义的帧格式RS422的通信方式。

然而，控制其整体采用CAN总线按照标准的扩展帧格式的通信方式。

主机监控所有控制器通过CAN总线网络。

本质安全网络信号通过隔离器连接所有控制单元和主机。

该控制器使用压力传感器、位置传感器和位移传感器来检测液压支架的工作状态，并利用CAN总线网络将信息传送到主机电脑，然后由电脑主机决定和实施液压支架的自动控制。

3.支撑控制器研究
控制器是电液控制系统核心。

控制器的设计水平决定该系统的整体水平。

外国的控制器通过使用处理器实现，德国的玛克（Marco），EE P和TIEFENBAC H等以及美国的公司都是如此。

国内个别业主或科研人员则是尝试使用可编程逻辑控制器（PLC）实现。

实践表明后者虽然具有相对高的抗干扰性能，但是因为体积大、笨重、设计不灵活的因素，无法实现应用程序（IAP）和自动识别自身地址的技术，导致它不适用于特殊的地下应用。

国外发展较早，所以绝大多数采用普通单片机作为为核心处理器。

目前随着技术的发展和进步，有许多高性能的处理器，如ARM，DSP等。

然而，在考虑设计的功能、功耗和总体成本等因素时，与MCS-51兼容的增强型处理器是更好的选择。

使用
处理器为核心的控制器，如图框图2。

图2 控制单元的方框图
控制器的外设配置不仅要满足当前的需求，也要具有可扩展性。

电磁先导阀的输出端的驱动器的数目是20。

模拟输入的数目通常是3，用于输入抽样信号的位移，压力和温度。

在未来的设计中数目为6，用以角度和多压力的测量。

并且，有两个开关输出接口为声光报警，两个开关输入接口用于在紧急停机开关和锁定切换。

此外，在硬件和软件的可靠性与传统的设计中，有三个特殊方法，即，闭环反馈机制，多控制驱动器输出机制和驱动停止联动机制。

首先，闭环反馈机制确保准确和可靠的驱动控制。

闭环反馈机制意味着比较由计算基本指令所得到的预期的输出状态和由处理器所采样的实际驱动的输出状态。

而且，如果比较的结果是相同的，所述处理器保持运行。

否则，采取措施，停止变频器的输出，立即避免生命和财产的损失。

其次，多控制驱动器输出机制表明，通过硬件的驱动指令的实施需要多个控制变频器的输出。

例如，在主电源开关关闭时，子开关接通不起控制作用。

因此，当子开关关闭不能硬件对硬件产生效果时，，它可以关闭主电源开关，停止意想不到的驱动器输出的动作。

最后是驱动器停止联动机制。

多站点的调查发现，煤矿工人在发生故障时习惯于使用紧急停机开关。

鉴于安全考虑，为了避免紧急开关的故障，该机制是紧急停机开关与在硬件电路的锁定开关相连接。

在这种情况下，按下紧急开关，这意味着同时按下锁定开关。

因此，如果紧急开关发生故障，锁定开关仍然工作以确保工人的安全。

该软件设计采用模块化的设计。

在不同的矿区搭配不同的液压支架，这会带来高性能的软件控制单的。

4.主机研究
电脑主机主要是由软件和硬件组成，通过连接现场总线与所有的控制器形成通信网络，实时监控每个液压支架的工作状态。

因为主机计算机在地下工作，它是必需得有防湿、防尘和防爆性能。

主机的设计也需要符合可扩展性和兼容性原则。

硬件设计需要充分考虑系统的可扩展性，充分支持硬件接口和软件性能。

与常见的计算机硬件和软件的相容性也很重要，以便它可以利用存
在的技术减少重复工作。

电脑主机通常是通过采用工业计算机和满足环保要求的防爆计算机实现，但它的可扩展性差，因此该系统的主机采用嵌入式PC104的定制方案。

主机计算机有大量的扩展接口，如RS232，RS485，CAN总线，光纤接口，电流环接口等。

每个接口都有符合安全标准的光电隔离电路，因此主机具有很强的可扩展性和很好的兼容性。

它可以直接连接到采煤机、破碎机、阶段装载器、刮板输送机和监测地下的设备通信接口，从而实现综采工作面全自动化。

图3 液压支架的应用软件的主界面
主机的监控功能是通过在嵌入式操作系统上运行的应用软件实现的。

应用软件包含后台数据处理部分和前台显示部分。

后台程序通过现场总线收集相关数据，处理后储在数据库中。

前台程序实现了读取、搜索数据库，并在主界面中显示，如图3所示。

表1 操作系统相比
该控制系统采用嵌入式Linux操作系统。

Linux操作系统和其他操作系统之间的比较显示在表1上。

从上面的表格可以看出，嵌入式Linux操作系统具有相当大的优势，如低成本，高度可定制的，稳定的运行和广泛的硬件支持，以及完全免费。

5.本质安全网络的研究
在现场总线使用中，德国EEP公司采用PROFIBUS技术实现信息的传递，而MARCO 公司使用自定义格式集电极开路技术。

目前，在国内使用的成熟的技术是由德国的BOTCH 公司所提出的CAN总线技术。

考虑到实际系统中庞大的数据传输，控制器之间的通信由全双工RS422技术来实现。

当在井下作业时，现场总线需要特殊处理。

因为本质安全的要求，电源装置的功率受到严格的限制。

根据电源装置、控制器和电流驱动阀门的总功率，通常每个电源只能提供五或六个控制器。

因此，系统需要大量的独立电源装置。

为了避免因电流不平衡导致失去内在安全性，在控制器之间的数据信号是由可切断电连接信号隔离器相连接。

6.总结
国在外现有技术的广泛调查的基础上，完成了液压支架电液控制系统设计和实现，并已通过了国家机构的认证资格。

在河南省平煤集团的工业性试验中该系统可靠运行三个月。

电液控制系统奠定了煤矿安全、高效生产的基础，将会使国内的全机械化采煤技术上升到新的台阶。

致谢
这篇研究报告是由中国人民科学技术部（国家863计划项目，项目编号2008AA062200）和中国煤炭工业协会（项目的号码是MTKJ08-301的）共同资助下完成。

The 6th International Conference on Mining Science & Technology Research on electro-hydraulic control system for hydraulic
support at coal mine
Yu Yuesen, Dai Peng, Xu Yajun, Peng Liming, Wu Xiaojie * School of Information and Electrical Engineering, China University of Mining and Technology, Xuzhou 221008, China
Abstract
Based on the investigation and analysis of the situation in full mechanized coal mining face at home and abroad, the electrohydraulic control system for hydraulic support is put forward, designed and realized. It adopted intrinsically safe circuit design technology and field bus technology to connect all control units to the host computer. Each control unit of the control system is equipped with one hydraulic support. Certain control unit(s) controlled by either the other control units or the host computer can operate adjacent support, distant support or a group of supports. Host computer in an explosion-proof housing also has the functions of real-time monitoring, remote control, fault diagnosis and upload data etc. The result of industrial experiment up to three months shows that the system works reliably and meets the design requirements.
Keywords: Hydraulic Support, Electro-hydraulic Control System, Host Computer
1.Introduction
Electro-hydraulic control system for hydraulic supports is the core of full mechanized coal mining face. And It can implement automatic control of production equipments and improve the production efficiency, working conditions and safety of coal mining face. The system based on network detects the position of the shearer and hydraulic supports automatically to achieve automatic control. Besides, it has the ability to monitor states of other equipments, to implement the communications between ground and underground computers and to complete the remote control. Compared with other industrial electro-hydraulic control systems, it has special characteristics, such as high pressure, anti-burning explosion-proof, dust-proof, anti-corrosion, anti-vibration and anti-electromagnetic interference.
Since the mid-1970's people abroad have started to study electro-hydraulic control system for hydraulic supports,launched the product after nearly a decade and perfected gradually the system after the 1990's. At present, many countries already have had mature products with different characteristics in the promotion stage, such as Germany, the United States, United Kingdom, Poland, Japan, France, and Russia etc.
At present, the control method of hydraulic supports made in China is mainly manual, which is equivalent to the control level of developed countries in the 1970’s. The electro-hydraulic control system equipped with hydraulic supports is manufactured in foreign countries, especially in Germany. The outstanding companies which have already come into
home market are DBT (its HQ is Bucyrus in the USA), Marco, EEP and TIEFENBACH in Germany and JOY in America. We have not achieved the target of industrialization and indigenization of the system, although our government has invested much in technical research of the electro-hydraulic control system for hydraulic supports from the 1990’s. In order to improve the level of mining equipments, strengthen the international competition and break through the international technical monopoly, it is urgent to research and produce utonomously electro-hydraulic control system for hydraulic supports.
2.Structure of the electro-hydraulic control system
Through the structure analysis of the electro-hydraulic control systems for hydraulic supports made by the EEP Company and Marco Company in Germany, combined with the actual application, block diagram of the self-designed electro-hydraulic control system is put forward and shown in Fig. 1.
Fig. 1. Block diagram of hydraulic supports electro-hydraulic control system
Electro-hydraulic control system for hydraulic supports mainly contains the control units, host computer and the intrinsically safe network. The support control unit includes the controller, sensors, electromagnetic pilot valves and main control valves. The control unit connects each other by the main cable. The controller adopts RS422 communication in accordance with self-definitional frame format. However, the overall adopts CAN bus communication in accordance with the standard extend frame format. The host computer monitors all controllers through the CAN bus network. The intrinsically safe network
connects all the control units and host computer by signal isolators. The controller uses t he pressure sensor, the position sensor and the displacement sensor to detect the working state of hydraulic supports and takes advantage of CAN bus network to transfer information to the host computer, then the host computer makes decision to implement the automatic control of hydraulic supports.
3.Research on support controller
The controller is the core of electro-hydraulic control system support. The design level of controller determines the entire level of the system. The foreign controller is achieved by using processors in not only the Germany companies, such as MARCO, EEP and TIEFENBACH and so on, but also the American companies. Domestic individual owners or scientific researchers try to use the programmable logic controller (PLC) to achieve the core processing. Practice shows that it has relatively high anti-interference performance, but is not suitable for special underground applications because of the factors such as large, bulky, designed inflexible, in application program (IAP) not achieved, self-address not automatic identification. Development in foreign countries is earlier, so the vast majority uses the ordinary MCU as the core processor. Currently with the development and progress of technology, there are many high-performance processors such as ARM, DSP etc. However, in consideration of the factors of design features, the power consumption and overall cost etc, the enhanced processor compatible with MCS-51 has been chosen. The block diagram of the controller using the processor as the core is shown in Fig. 2.
Fig. 2. Block diagram of control unit
Peripheral configuration in the controller is considered to meet not only the current needs but also the expansibility. The number of the drive outputs for electromagnetic pilot valves is 20. The number of the analog input is usually 3 used for sampling signals of displacement, pressure and infrared. And the designed is 6 for the measurement of the angle and multi-pressure in the future. In addition, there are two switching output interfaces for the sound and light alarm and two switching input interfaces for the emergency shutdown switch and the lock switch.
I n addition to conventional design for reliability in hardware and software, there are three special treatments used, namely, the closed-loop feedback mechanism, the drive output of multiple control mechanism and the drive stop linkage mechanism. Firstly, the closed-loop feedback mechanism ensures the drive control accurate and reliable. The closed-loop feedback mechanism means comparing the drive actual output state sampled by the processor with the expected output state calculating on the basis of the command. And if the compared result is the same, the processor keeps running. Otherwise, it takes measures to stop the drive output immediately avoiding losing of life and property. Secondly, the drive output of multiple control mechanism indicates that the implementation of the drive command needs multiple-control through hardware. For example, before the main switch is off, the sub-switch turned on can not implement the action. Therefore, when the sub-switch turning off cannot take effect in hardware, it is possible to turn off the main switch to stop the unexpected drive output action. The last is the drive stop linkage mechanism. The multiple-site survey has found that mine workers are used to use emergency shutdown switch to stop action in the event of failure. In order to avoid failure of the emergency switch concerning the safety, it is linked with the lock switch in the hardware circuit. In this case, when the incident occurred, pressing the emergency switch, means pressing the lock switch simultaneously. So if the failure of the emergency switch occurs, the lock switch still works to ensure the safety of workers.
The modular design is adopted in software design. Different hydraulic shields are collocated at different mines. And this brings the differences in software for high performance of control unit.
4.Research on host computer
Host computer is mainly composed of software and hardware, and it forms communications network through field bus and all controllers, which is real-time monitoring the work states of every hydraulic support. Because the host computer works underground, it is required that it should have a moisture-proof, dust-proof and explosion-proof performance. Design of the host computer also needs to meet the principle of expansibility and compatibility. The proceeding of hardware design demands fully considering system expansibility, which is supported by hardware interface and software performance. The compatibility of hardware and software with the common computer is also important, so that it can utilize the technology in existence and reduce duplicated effort. Host computer usually is realized through adopting industrial computer and explosion-proof computer which satisfy the environmental requirements, but its expansibility is poor. So the host computer of this system adopts customized scheme with embedded PC104.
Host computer has a lot of extended interfaces, such as RS232, RS485, CAN bus, fiber interface and current loop interface and so on. Each interface has a photoelectric isolation circuit which is in compliance with the safety standards, thus the host computer has very strong expansibility and very well compatibility. It can connect directly to communication interfaces of the shearer, crusher, stage loader, scraper conveyor and monitor underground
equipments, so as to realize the automation of full mechanized coal mining face.
Fig. 3. The main interface of application software for hydraulic supports
The monitoring function of the host computer is achieved by application software running on the embedded operating system. The application software consists of background data processing section and foreground display section. Background program collects relevant data through field bus and stores in the database after processing. Foreground program achieves the read and search of the database and displays the data in the main interface which is shown in fig.3
Table 1. Operating systems compared
Item Windows Dos Vxworks Linux
Cost Not free Not free Expensive Free
Customizing not bad Bad Well Very well
Source code Not open Not open Not open Open
Real time performance Bad Bad Well Commonly
Hardware Well Well Well Well
Function Multitask Single-task Multitask Multitask
This control system uses the embedded Linux operating system. And the comparison between Linux operating system and other operating systems is shown in table.1.
It can be seen from the above table that the embedded Linux OS has considerable advantages such as completely free of cost, highly customizable, stable operation and a wide range of hardware support.
5.Research on the intrinsically safe network
In field bus use, EEP Company in Germany adopts profibus technology to achieve information transfer, while MARCO Company uses the custom format open collector technology. At present, the mature technology widely used in domestic is CAN bus technology put forward by BOTCH Company in Germany. Communication between controllers is achieved by full-duplex RS422 technology in consideration of the vast transferred data in the actua system.
Field bus needs special treatment when working underground. And because of the request of intrinsically safe,the power of the power supply subjects to strict limitations. Usually each power supply can only supply five or six controllers according to the power of power supply, controllers and current-driven valves. Thus a large number of independent power supplies are needed for the system. In order to avoid current imbalance leading to lose intrinsic safety, the data signal between the controllers is communicated by signal isolators which can cut off electrical connection.
6.Conclusion
Basing on wide investigation of existing technology abroad, the electro-hydraulic control system for hydraulic supports was designed and realized, and it has passed the national institutions certification examination. The system has run reliably for three months in industrial experiment at Pingmei Group in Henan province. The electrohydraulic control system has laid the foundation successfully for safe and high efficient coal mine, which improves significantly the domestic automation level of full mechanized coal mining face. Acknowledgements
The research reported in the article was funded by the Ministry of Science and Technology of the People's Republic of China (National 863 plans projects. Project Number is 2008AA062200) and China Coal Industry Association (Project Number is MTKJ08-301). References
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