并联LC网络的软开关三管推挽式直流变换器  

A Soft-switching Three-transistor Push-pull DC/DC Converter With LC Net in Parallel

作　　者：袁义生[1] 伍群芳[1] 

机构地区：[1]华东交通大学电气学院,江西省南昌市330013

出　　处：《中国电机工程学报》2013年第24期42-51,8,共10页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51067004);江西省科技支撑项目(2010BGA02000);江西省教育厅科研项目(GJJ12293)~~

摘　　要：提出一种采用3个开关管的软开关推挽电路。增加的开关管Q3串接在输入电源和变压器原边绕组中间抽头之间。一个LC网络并联在Q3两端。因为输出滤波电感能量大,2个原始的开关管能够在宽负载范围内实现零电压开通。并联的LC网络增加了Q3开通前变压器漏感中的能量,使得Q3也能在宽负载范围下实现零电压开通。分析电路各工作阶段原理,讨论软开关实现条件,阐述LC器件的设计。完成一台800W、开关频率为132kHz的原理样机,样机在86 W下就能实现所有开关管的零电压开通,样机最高效率达到94.14%。测试比较了所提电路和基本的三管推挽电路的效率,结果表明,所提电路在轻载下比基本电路效率高2.31%。One three-transistor push-pull converter （TTPP converter） was proposed. The additional transistor Q3 is inserted between the input power source and midpoint of primary windings of the transformer. One LC element parallels with the transistor Q3. Two primitive transistors can realize zero-voltage turn-on because of the big energy of output inductor Lf. The LC net increases the energy of the leakage inductance before Q3 turn-on. As a result, Q3 can also achieve zero-voltage turn-on over a wide load range. The operation theory was discussed. The ZVS conditions of the three transistors were explained. The design of the LC net is investigated. A 800 W, 132 kHz prototype was built. Tests showed all power transistors can achieve ZVS at 86 W load. The peak efficiency of the prototype reaches 94.14 %. Comparing the proposed TTPP converter with the basic TTPP converter, the efficiency of proposed converter is 2.31% higher than that of the basic converter.

关 键 词：三管推挽式(TTPP)变换器 零电压开通 LC网络 

分 类 号：TM46[电气工程—电器]