本科生毕业设计（论文）
摘 要
开关电源具有效率高、体积小、重量轻等显著特点。目前世界各国都有广泛的应用，特别是对大容量高频开关电源的研究和开发已成为当今电力电子学的主要研究领域，并派生了很多新的研究方向。
本设计的题目为10kW直流开关电源的设计，直流开关电源的工作原理：电网输送来的交流电经整流滤波电路变为直流，经过高频逆变电路变为高频交流，通过高频变压器将高频交流电变压，然后高频交流电经单相桥式整流滤波电路变为直流。根据直流开关电源的工作原理确定设计方案，选择三相桥式不控整流滤波电路作为主电路的输入级电路，通过分析比较各种变化器的优缺点，选用移相式全桥变换器，设计了高频变压器，选择单相桥式整流电路作为主电路的输出级电路，在电压调节环节上，详细分析了基于UC3825控制芯片的PWM控制电路。并根据任务要求完成了IGBT驱动电路、系统反馈电路的、保护电路、辅助电源以及均流电路的设计。
本次设计的10kW直流开关电源具有输出电压可调、输出电流大、纹波小等特点。实验结果表明它基本达到设计要求，从而验证了理论分析的正确性，具有广阔的应用前景。
关键词：变换器；开关电源；高频变压器；PWM控制
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本科生毕业设计（论文）
Abstract
Switching power supply with high efficiency, small size, light weight and other significant characteristics. At present, all the countries in the world have a wide range of applications, especially in the research and development of large capacity and high frequency switching power supply has become a main research field of modern power electronics, and derive a lot of new research directions.
The subject of this design is the design of 10kW DC switching power supply, the working principle of DC switching power supply: the grid to the AC rectified filter circuit into a DC, after high frequency inverter circuit into a high-frequency alternating current, high frequency alternating current transformer by high-frequency transformer will, then high frequency AC single-phase bridge rectifier filter circuit for dc. According to the design scheme to determine the working principle of DC switching power supply, selection of three-phase uncontrolled rectifier filter circuit as the input circuit of main circuit, comparing the advantages and disadvantages of various changes through the analysis, selection of phase-shift full bridge converter, high frequency transformer design, selection of single phase bridge rectifier circuit as output circuit of the main circuit, on the voltage regulation part, a detailed analysis of the UC3825 control chip control circuit based on PWM. And the IGBT drive circuit, feedback circuit, protection circuit, auxiliary power supply and a flow equalization circuit is designed according to the requirement of the task.
The design of 10kW DC switching power supply has the characteristics of adjustable output voltage, output current, low ripple. The experimental results show that it meets the design requirement, which verifies the correctness of the theoretical analysis, has a broad application prospect.
Keywords: converter；Switching power supply；high-frequency transformer；PWM control
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本科生毕业设计（论文）
目 录
第1章 绪论 ............................................................................................................ 1
1.1 开关电源的简介 ....................................................................................... 1 1.2 开关电源的发展及国外现状 ................................................................... 1 1.3 国内开关电源的发展及现状 ................................................................... 3 第2章 系统分析和设计方案确定 ........................................................................ 5
2.1系统整体概述 ............................................................................................ 5 2.2变换器的选择 ............................................................................................ 6 2.3控制电路的实现 ........................................................................................ 6 2.4 整流滤波电路的选择 ............................................................................... 8
2.4.1 输入整流滤波回路 ........................................................................ 8 2.4.2 输出整流滤波回路 ........................................................................ 8
第3章 开关电源主电路的设计 ............................................................................ 9
3.1 开关电源的设计要求 ............................................................................... 9 3.2 主电路组成框图 ....................................................................................... 9
3.2.1 输入整流滤波电路 ...................................................................... 10 3.2.2移相式全桥变换器的设计 ........................................................... 12 3.2.3 输出整流滤波电路 ...................................................................... 16
第4章 控制电路的设计 ...................................................................................... 19
4.1 PWM集成控制器的基本原理 ................................................................ 19 4.2 高速脉宽调制器UC3825 ....................................................................... 19
4.2.1 主要特点 ...................................................................................... 21 4.2.2 极限参数 ...................................................................................... 21 4.2.3 内部电路工作原理 ...................................................................... 22 4.3 UC3825的调试 ........................................................................................ 24 4.4 反馈电路的设计 ..................................................................................... 25 第5章 保护电路的设计 ...................................................................................... 28
5.1 软启动电路的设计 ................................................................................. 28 5.2 过流过压保护 ......................................................................................... 29 第6章 辅助电源设计 .......................................................................................... 32 第7章 均流电路设计 .......................................................................................... 34
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