5kw移相全桥ZVS DCDC变化器(开关电源)的研究要点

学校代码：10213

国际图书分类号：621.3 密级：公开

工学硕士学位论文

5kW 移相全桥ZVS DC/DC 变换器的研究

硕士研究生：刘鑫

导师：马洪飞教授

申请学位：工学硕士

学科：电气工程

所在单位：电气工程及自动化学院

答辩日期：2011 年6 月

授予学位单位：哈尔滨工业大学r the Master Degree in Engineering

RESEARCH ON 5kW PHASE-SHIFT FULL BRIDGE

ZVS DC/DC CONVERTER

Candidate：Liu Xin

Supervisor：Prof.Ma Hongfei

Academic Degree Applied for：Master of Engineering

Speciality：

Power Electronics and Electric

Drivers

Affiliation：

School of Electrical Engineering and

Automation

Date of Defence：

June, 2011

Degree-Conferring-Institution：Harbin Institute of Technology哈尔滨工业大学硕士学位论文- I -

摘要

DC/DC 变换器是电力电子领域重要组成部分，在能源紧张的今天，提高DC/DC

变换器的效率及功率密度，具有重要的意义。功率器件的发展和软开关技术的提

出使变换器高效高功率密度成为可能。

移相全桥ZVS DC/DC 变换器是一种能够实现软开关和大功率能量变换的变换

器。本文围绕移相全桥ZVS DC/DC 变换器的特点，分析了其工作原理、占空比丢

失、变压器副边整流二极管振荡、滞后臂软开关实现条件等关键问题，并设计和

制作了一款5kW 的原理样机。

第一章介绍了DC/DC 变换器的背景及发展方向，其中包括器件、软开关技术

和目前DC/DC 变换器研究的热点。同时还介绍了全桥变换器常见的控制策略，以

及移相全桥变换器常见的问题和国内外学者提出的改进方法。第二章针对课题内

容，分析了移相全桥变换器的工作原理，对各个模态进行了详细的分析，并就移

相全桥变换器的几个关键问题进行了详细分析：占空比丢失、ZVS 的实现、损耗

分析和整流二极管振荡问题。第三章针对技术指标，设计了一款5kW 的样机，其

中包括各器件的选型和相关参数的计算，损耗计算。这些参数计算主要有：全桥

开关管电压电流应力的计算与选型、变压器的设计、整流二极管的选择、输出LC

滤波电路的设计、隔直电容的选择、谐振电感电容的选择和死区时间的计算、箝

位电路的设计。并根据计算结果使用Saber 软件进行了开环仿真，验证了设计参数

的正确性。第四章主要介绍了变换器控制系统分析与设计，其中有控制芯片

UCC2895 的功能介绍，外围元件的选择与保护与采样电路的设计，移相全桥ZVS

DC/DC 变换器的小信号模型和利用MATLAB 软件进行反馈回路的补偿设计。第五

章给出了实验结果和分析，验证了设计的正确性。

关键词移相全桥；软开关；UCC2895；小信号模型硕士学位论文

5kW 移相全桥ZVS DC/DC 变换器的研究

RESEARCH ON 5kW PHASE-SHIFT FULL BRIDGE

ZVS DC/DC CONVERTER

刘鑫

哈尔滨工业大学

2011 年6 月哈尔滨工业大学硕士学位论文

- II -

Abstract

DC/DC converter is a main part of power electronic converter. As the energy

problem increasingly concerned in modern society, improving the efficient and power

density have the significant advantages. The developing of power device and invention

of soft-switching technique make the high efficient and high power density of DC/DC converter possible.

The zero-voltage-switching (ZVS) phase-shift full bridge DC/DC converter is an

advanced DC/DC converter with soft-switching technology which can achieve high

power converting. Based on the characteristics of the converter, this paper analyses the

basic operation theory and some typical problems like secondary duty ratio loss and the parasitic oscillation of output rectifier diodes as well as the difficulty for lagging legs

achieve ZVS. The simulation and experiments are also given.

Firstly, this paper introduces the background and development of the converter,

including power device and soft-switching technology and the hot points in

researching DC/DC converter as well as some typical problems and some

improvements. Secondly, this paper analyses the basic operation theory and some

typical problems like secondary duty ratio loss and the parasitic oscillation of output

rectifier diodes and power losses as well as the difficulty for lagging legs achieve ZVS.

Thirdly, this paper calculates the main parameters including the selection of bridge

MOSFET and the design of transformer as well as the output filter and so on. The last

of the third part uses the software SABER to simulate the main circuit to verify the

correction of the calculations. Fourthly, this paper introduces the control system of the converter including the UCC2895 chip, sampling circuit, protection circuit, and the

small signal model of the converter, as well as the compensation of the feedback

loops.

Eventually, the paper explains the experimental result and analyzes the result in

detail.

Keywords phase shift full bridge, soft-switching, UCC2895, small signal model哈尔滨工业大学硕士学位论文

- III -

目录

摘要............................................................................................. I