高频软开关技术研究与应用

【作者】 刘平；

【导师】 刘烈峰； 任先文；

【作者基本信息】 中国工程物理研究院 ， 脉冲功率技术及其应用， 2013， 硕士

【摘要】 一些特种电源需要输出大功率、大电流或高电压的电源,且工作在特殊环境下,要求体积小、重量轻、散热和电磁兼容好。高频软开关技术应用于特种电源具有明显的优势：开关频率高,电源体积和重量小,开关损耗少,电磁兼容好,半导体功率器件的效能高。高频软开关技术应用于大功率特种电源时主要有两种典型的电路结构：全桥移相软开关电路和全桥串联谐振软开关电路。全桥移相软开关电路多用于大功率、大电流电源,其开关管的通态损耗小、电源效率高。全桥串联谐振软开关电路具有恒流输出特性、抗短路性能好,多用于高压脉冲电容器的充电电源。本文分析了这两种软开关电路的工作过程,实现软开关的原理,存在的问题,提出了改善的措施,在此基础上研制了两种电源系统。内容分为以下两部分：(1)系统研究了全桥移相软开关电路的工作过程和滞后臂零电压开通问题。采用了可饱和电感代替线性谐振电感,以解决滞后臂零电压开通问题,并对带可饱和电感的全桥移相软开关电路工作原理作了分析；研究了开关管并联电容对其损耗的影响,并通过仿真,分析了合理增大开关管并联电容以改善开关管损耗的可能性。在此基础上,研制了一台5kW的试验样机。(2)研究分析了串联谐振电路拓扑结构、工作过程和实现软开关的原理,以及串联谐振电路恒流充电的条件和优势,在此基础上研制了一套串联谐振充电电源,应用于高压脉冲电源系统。更多还原

【Abstract】 Some kinds of special power supplies which need to output high power, large current or high voltage and work in special circumstances, are required small volume, light weight, less heat dissipation and EMC. The high-frequency soft switching technology applied to the special power supplies has predominant advantages:higher switching frequency, less volume and weight, less switching energy loss, better EMC and better the performance of semiconductor devices.There are two kinds of typical circuits in the high-frequency soft switching technology applied to high power special power supplies:the full-bridge phase-shifted soft switching circuit and the full-bridge series resonant soft switching circuit. The former is usually applied to power supplies that output high power and high current with less on-state loss and higher efficiency. The latter is usually used in the charging power supplies of high voltage pulse capacitors with constant current output characteristic and high capability of anti-short-circuit.The working process of the two kinds of circuits, the principles of achieving soft switching and their problems are analyzed. Some measures are proposed and two power supplies are developed in the paper. The content is divided into two parts:(1) The working process of the full-bridge phase-shifted soft switching circuit and the ZVS problem of the lagging leg are analyzed in detail. A saturable inductor, in stead of a linear inductor, is used to solve the ZVS problem of the lagging leg, and the working process and the principle are studied. The influence of switches’parallel capacitors on switching energy loss is researched. On the base of these studies, a5kW experimental prototype is developed in the paper.(2) The working process and the principle of the full-bridge series resonant soft switching circuit are studied. The conditions and advantages of its constant current charging characteristic are analyzed. On the base of these studies, A series resonant charging power supply applied to high-voltage pulse generator system is developed in the paper.更多还原