ZVS三管推挽直流变换器  

ZVS Three-transistor Push-pull DC/DC Converters

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》2012年第33期23-30,171,共8页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51067004)~~

摘　　要：提出一种采用3个开关管的推挽式(three-transistorsPush-Pull,TTPP)变换器,仅需要在传统推挽变换器的输入电源和变压器两个原边绕组中点间插入一个辅助开关管Q3。两个主管驱动信号ugs1和ugs2与传统推挽变换器中开关管的驱动信号相反;除去死区时间,辅管驱动信号ugs3是两个主管驱动信号ugs1和ugs2的与非关系。用等效电路的方法结合解析方程,分析电路各个工作模态的工作原理和主要开关波形。指出主管可在宽负载范围下实现零电压开通(zerovoltage switching,ZVS),且主管关断电流是传统推挽电路中的一半值。辅管在大负载或加大漏感情况下可以实现ZVS开通,辅管的额定电压是主管的一半,等于输入电压。讨论软开关的实现问题。提出控制芯片及其驱动电路的设计方法,完成一台800W、开关频率为83.3kHz的原理样机,实验结果验证了该变换器工作原理的有效性。A three-transistor push-pull（TTPP） converter was proposed in this paper.An auxiliary transistor Q3 is inserted between the input power source and midpoint of two primary windings in a traditional push-pull converter.The driving signals ugs1 and ugs2 of two main transistors are as inversely as that in traditional push-pull converter.Except for the dead time,the driving signal ugs3 of the auxiliary transistor is equal to the inverse of ugs1 ugs2.By building the equivalent circuits and analytic equations,the operation theory and main switching waveforms of each operation modes were analyzed.Its main transistors can achieve ZVS under wide load range and turn off under half the current occurred in a traditional push-pull converter.The auxiliary transistor can realize ZVS under heavy load or with large leakage inductance.The rated voltage of the auxiliary transistor is half of that of the main transistors and is equal to Uin.The soft-switching conditions were discussed.The PWM IC and driving circuit were presented.A 800？W,83.3？kHz prototype was built.The experimental result verified the discussed theory correctly.

关 键 词：推挽变换器 辅管 零电压开关 占空比丢失 移相全桥电路 

分 类 号：TM46[电气工程—电器]