摘要随着节能环保意识不断增强和现在对电力电子方面的不断开发应用,低功耗电子产品的市场不断壮大，高效率开关电源的研究引起了各个公司及设计人员的关注和重视，特别是交直流转换的开关电源。然后，基于IC控制的普通开关电源又存在灵活性和通用性差的问题，针对普通开关电源的缺点进行了创新性设计。33221
本文首先阐述开关电源的背景和发展状况，提出基于可编程控制器的PWM型开关电源的设计,采用集成有PWM模块的PIC类单片机代替传统的IC芯片。对常见使用的拓扑结构的基本原理简明阐述并以此作比较，选用半桥变换器并完成对主电路的选择和设计。对主要控制方式进行了仔细分析，通过输出电压的采样和设定值参与单片机内部PID运算从而控制占空比的控制方式，完成对PIC单片机进行程序流程图的设计。最后完成了对单片机供电等辅助电路及抗干扰的设计并对主电路进行了仿真，仿真结果基本满足设计要求。
设计的开关电源在仿真中能够稳定地输出电压，但是在绝缘耐压，耐温耐湿等问题略显不足。总体来说本设计基本满足了设计要求。
毕业论文关键词：开关电源；PIC；PWM；PID
Abstract
With the growing of energy saving consciousness and the development of power electronics, the lower-power consumer electronics market is growing, especially in AC/DC switching power converters to high-profile. However, the traditional switching power supply based on IC has low popularity and intelligence. This innovative design was made to solve this problem.
First the background and development status of switching power supply is expound, then the design of PWM mode switching power supply is present based on the programmable controller, use MCU which contain PWM module to replace PWM chip. The chose and design of main circuit by contrasting the topology. The main control mode were carefully analyzed, by sampling feedback circuit isolates and amplifies the output voltage, then send it to MCU for the PID compute, to control the PWM wave’s duty ratio,complete the program flow chart of PIC single chip design. Finally complete the other auxiliary circuit and anti-jamming,then simulate the main circuit and it met the requirement basically.
The design of power supply can output the voltage steadily.But there are some problem such as wet-resistance and heat resistant weren’t be solved .In general the design met the requirements basically.
Key word:Switching-mode power supply； PIC； PWM； PID
目 录
摘 要 I
Abstract II
1 绪论 1
1.1开关电源简介和发展 1
1.2控制方式的选择 2
1.3本课题设计背景 3
1.4主要工作及内容 4
2 拓扑结构基本原理及主电路的选择 5
2.1广泛使用的几种基本拓扑结构 5
2.2非隔离型变换器 5
2.3隔离型变换器 7
2.4主电路（半桥式）的选择 10
2.5本章小结 10
3 开关电源主电路设计部分 11
3.1开关电源整体设计 11
3.2变压器的设计 12
3.3功率半导体器件的选择 15
3.4输出滤波器的设计 16
3.5栅极驱动变压器的设计 17
3.6整流器和输入滤波器电路的设计 18
3.7本章小结 18
4 控制电路的设计 20
4.1开关电源控制方式的选择 20
4.2开关电源中PID的运用 22 基于单片机PWM控制开关电源的设计+电路图:http://www.751com.cn/zidonghua/lunwen_30181.html