基于UC3844通用变频器辅助电源的研究设计
基于UC3844通用变频器的辅助电源的研究设计
摘 要 ：通用变频器作为早个商品开始在国内上市，是最近十年内的事情，并且销
售额逐年增加，至今为止全年有超过数十亿元（RMB）的市场。对于许多用户而言,这十年中历经多次更新，现在所使用的变频器大部分属于目前最先进的机型。若从应用的角度来说，我们的水准与发达国家已经很接近。
本课题是设计一个通用变频器的多路输出的反激式开关电源，电源取高压直流（DC 350V-700V）。要求基于UC3844专用PWM发生芯片，采用反激变换器结构的高压直流（DC 350V-700V）输入多路（5路：24V/200mA；±15V/200mA；5V/1A）隔离输出。设计完成的该系统应符合各项行业规定。
关键词：UC3844、开关电源、反激变换器
I
基于UC3844通用变频器辅助电源的研究设计
Design of auxiliary power supply based on UC3844
general inverter
Abstract：As a goods start early in the domestic market, is nearly a decade,general converter sales increased year by year, this year more than billions of yuan (RMB) in the market. For many users, this decade has been a lot of time to update, now the frequency converter used mostly belongs to the most advanced models if from the point of view of application, we have very close to level with the developed countries.
This topic is to design a general inverter multiplexed output of the flyback type switch power supply, power supply from high voltage direct current (DC 350 v - 700 - v). Requirements based on UC3844 dedicated PWM chip, adopt the structure of the flyback high voltage direct current (DC 350 v - 700 - v) input multiplexer (24 v / 5:200 ma, + 15 v / 200 ma; 5 v / 1 a) isolation of the output. Design of the system should comply with the regulations of the industry.
Keywords: UC3844，Switching Power Supply，The flyback converter
II
基于UC3844通用变频器辅助电源的研究设计
目录
基于UC3844通用变频器的辅助电源的研究设计 ................................. I Design of auxiliary power supply based on UC3844 general inverter ........ II 前 言 .................................................................... 1 第一章 绪论 .............................................................. 2
1.1 通用变频器的发展 .................................................. 2 1.2 通用变频器工作原理 ................................................ 3
1.2.1变频器的基本控制方式 ......................................... 3 1.2.2 变频器输出电压调制和PWM技术 ................................. 5 1.3 通用变频器的开关电源简介 .......................................... 7
1.3.1 开关电源的发展 ............................................... 7 1.3.2开关电源的优点 ： ............................................ 9 1.3.3 开关电源的构成 ............................................... 9 1.3.4保护电路 .................................................... 14 1.3.5开关电源中的辅助电源 ........................................ 15 1.4 UC3844芯片介绍 ................................................... 17 1.5 课题来源及主要研究内容 .......................................... 18
1.5.1课题来源 .................................................... 18 1.5.2 主要研究内容 ................................................ 19
第二章 开关电源的设计 ................................................... 20
2.1 主电路拓扑 ....................................................... 20 2.2主要器件介绍 ...................................................... 20
2.2.1 PC817 ....................................................... 20 2.2.2 TL431 ....................................................... 21 2.2.3 开关功率管的选择 ............................................ 22 2.3 变压器设计 ....................................................... 23
2.3.1 计算一次绕组参数 ............................................ 23 2.3.2计算磁芯参数 ................................................ 24 2.3.3 计算变压器有效体积 .......................................... 25 2.3.4确定一次绕组匝数N1 .......................................... 25 2.3.5 确定自馈绕组N2和二次绕组N3 的匝数 ......................... 26 2.3.6 计算空气气隙? .............................................. 27 2.4缓冲电路设计 ...................................................... 28 2.5驱动电路和控制电路设计 ............................................ 30 2.6电流反馈电路设计 .................................................. 31 2.7电压反馈电路设计 .................................................. 32 第三章 斜坡补偿 .......................................................... 34
3.1 斜率补偿的类型与补偿方程 ......................................... 34 3.2 正斜率补偿及其补偿电路 .......................................... 35 4.3 正斜率补偿的电路优化 ............................................ 36 结束语 ................................................................... 38 参考文献 ................................................................. 39
基于UC3844通用变频器辅助电源的研究设计
致 谢 ................................................................... 40 附 录 ................................................................. 41