小型高频开关电源的设计 学位论文.doc

University of Science and Technology Liaoning 毕业设计 论文题目：小型高频开关电源的设计 学 院： 电子与信息工程学院 班 级： 自动化2011-6 小型高频开关电源的设计 摘 要 在各种电力电子设备中，开关电源作为其供电装置必不可少。一个完整的开关电源系统主要由输入电路、开关变换器、变压器、输出电路、控制电路等几部分组成，将交流输入电转换成电力电子设备所需的直流电。现阶段开关电源主要向高频化、集成化、智能化等方向发展，对电力电子设备性能的提高扮演了举足轻重的角色。本文针对电动汽车电驱动系统的电源需求，设计一款小型高频开关电源，以期实现宽范围电压输入和多路隔离输出的问题。选择单端反激式拓扑，高频变压器采用耦合方式实现小型开关电源的多路隔离输出。基于单端反激式变换器原理及电流型PWM控制芯片，本文设计了一个单端反激式多路输出小型高频开关电源，主要介绍了单端反激变换器、RCD箝位电路、UC3842芯片、电压及电流反馈电路的设计过程。 关键词：开关电源；单端反激式变换器；高频变压器；电流型PWM控制；UC3842 Small High-frequency Switching Power Supply Design Abstract In various power electronic devices, switching power supply device as playing an important role. A complete switching power supply system consists of an input circuit, switching converters, transformers, output circuit, a control circuit composed of several parts, the AC input power is converted into direct current required to power electronic devices. At this stage mainly to the high-frequency switching power supply, integration, intelligence and other direction, to improve the performance of power electronics played a pivotal role.In this paper, the power requirements of the electric vehicle electric drive system, a small high-frequency switching power supply design, in order to achieve a wide range of input voltage problem and multi-channel isolation output. Choose single-ended flyback topology, high-frequency transformer coupling achieve small switching power supply multi-channel isolation output. Based on a single-ended flyback converter principle and current mode PWM control chip, the article gives a single-ended flyback multi-output compact high-frequency switching power supply design, introduced the flyback transformer, RCD clamp circuit, UC3824 start circuit, voltage feedback circuit and current feedback circuit design process. Keywords: switching power supply; single-ended flyback converter; high-frequency transformers; current-mode