低整流电压应力的推挽正激三电平变换器  

Push-Pull Forward Three-Level Converter with Reduced Rectifier Voltage Stress

作　　者：姚志垒[1,2] 肖岚[1] 黄勇[1] 丁连锋[1] 

机构地区：[1]南京航空航天大学航空电源航空科技重点实验室,南京210016 [2]盐城工学院电气工程学院,盐城224051

出　　处：《电工技术学报》2012年第9期231-236,241,共7页Transactions of China Electrotechnical Society

基　　金：国家973计划(2007CB210303);国家863计划(2011AA11A249);江苏省优势学科建设资助项目

摘　　要：提出了一种推挽正激三电平变换器。它适合于低压宽输入的场合,如可再生能源。该变换器的一半开关管承受1/2的输入电压,另一半承受3/2的输入电压。采用传统的三电平控制策略,并考虑变压器漏感在整流二极管上产生的电压尖峰,整流二极管的电压应力高,尤其是在高输出电压的场合。为了解决上述问题,采用二次整流电压波形先出现1/2电平,后出现1电平的控制策略,并通过在整流二极管上并联电容的方法,降低了整流二极管的电压应力。该文详细分析了该变换器的工作原理,讨论了整流二极管并联电容的选取。最后,以一台500W的原理样机对理论分析并进行了实验验证。This paper presents a push-pull forward （PPF） three-level （TL） converter, which is suitable for low and wide-range input voltage applications, such as renewable energy resources. Half of the switches sustain half of the input voltage, and the others sustain one and one-half input voltage. However, voltage stress of the rectifier diode is high with the conventional TL control strategy, especially in high output-voltage condition, considering voltage spike across the rectifier diode caused by leakage inductance. When 1/2 level of the secondary rectified voltage shows first and 1 level of that appears later, the voltage stress across the rectifier diode can be reduced by paralleling with external capacitor. The operating principle and selection of the external capacitor are analyzed. Finally, experimental results of a 500 W PPF TL converter verify the theoretical analysis.

关 键 词：可再生能源 三电平 直直变换器 推挽正激 电容 

分 类 号：TM13[电气工程—电工理论与新技术] TM46