最新交错并联式双管正激变换器及其控制电路毕业

交错并联式双管正激变换器及其控制电路

毕业

摘要

本文主要研究了交错并联式双管正激变换器及其控制电路。相比于其他隔离式DC/DC变换器，交错并联结构的双管正激变换器有自动实现励磁能量的回馈，结构简洁等优点。同时，其主功率管只需承受电源电压，从而选择面更广。此外，其并联结构缩小了输出滤波电感的体积，降低了器件的应力，从而进一步减小了损耗。在控制电路的设计方面，考虑到电源输出电压范围的可控性，本文采用电压反馈控制方式，选用UC3825型脉宽调制器。本文列举了DC/DC变换的各种拓扑，比较了四种PWM控制模式，分析了交错并联式双管正激变换器的工作原理及其工作过程，详细推导并建立了带有电压反馈控制的双管正激变换电路的小信号模型，设计了补偿网络，给出了主电路和控制电路的工程计算。最后，对系统进行频域、时域仿真，并给出相关分析。

关键词：双管正激变换器、电压反馈控制、小信号模型、补偿网络、仿真

Abstract

This paper studies the parallel dual interleaved forward converter and its control circuit. Different to other isolated DC/DC converters, the parallel dual interleaved forward converter can feedback excitation energy automatically, also, simple structure is the one of the system’s advantages. Meanwhile, the power switches only need to work just under the main power voltage, which makes the designers have a wider range of choosing the power switches. In addition, the parallel structure reduces the volume of the output filter inductance, reducing the stress of the device, thereby, further reducing the loss. In the control circuit design, taking into account of the controllability of the range of the output voltage, we use voltage feedback control method, and chose the UC3825 voltage pulse width modulator. This article lists the DC/DC conversion of the various topologies, makes a comparison of the four PWM control modes, analyzes the parallel dual interleaved forward converter’s operating principle and working process, derives in detail and establish the small signal model, designs the compensation network, and carries out the main circuit’s and control circuit’s engineering calculation. Finally, this paper makes the system frequency and time domain simulation, and make some correlation analysis.

Key words: dual forward converter, voltage feedback control, small signal model, compensation network, simulation

目录

摘要........................................................................................................................... I Abstract .......................................................................................................................... I 目录.......................................................................................................................... II 第1章绪论. (1)

1.1开关电源概述 (1)

1.2本课题研究意义 (1)

1.3隔离式DC/DC变换拓扑列举 (2)

1.4反馈控制模式分类 (4)

1.5本课题方案研究 (7)

1.5.1功率电路选择 (7)

1.5.2控制电路的选择 (8)

1.6本文研究的主要内容 (8)

1.7本章小结 (8)

第2章功率电路状态分析及其参数设置 (9)

2.1功率电路结构及其工作原理分析 (9)

2.1.2电路结构分析 (9)

2.1.2功率电路工作原理分析 (9)

2.2主电路参数设计 (14)

2.2.1技术指标 (14)

2.2.2功率电路变压器设计 (15)

2.3.3主功率开关管的选择 (19)

2.3.4二极管的选择 (19)

2.3.5输出滤波电感的选择 (20)

2.3.6输出滤波电容的选择 (21)

2.4本章小结 (21)

第3章系统建模与控制电路的设计 (22)

3.1功率电路建模 (22)

3.1.1小信号模型的建立 (22)

3.1.2标准型等效电路的建立 (25)

3.2电压控制脉宽调制器建模与系统稳态传递函数的建立 (28)