临界模式混合光伏微型逆变器的特性分析  

Characteristics Analysis for a Boundary Conduction Mode Hybrid-Type Photovoltaic Micro-Inverter

作　　者：张峰 谢运祥[1] 胡炎申 陈刚 王学梅[1] Zhang Feng;Xie Yunxiang;Hu Yanshen;Chen Gang;Wang Xuemei(School of Electric Power South China University of Technology,Guangzhou 510640 China;Shenzhen MOSO Electric Co.Ltd,Shenzhen 518131 China)

机构地区：[1]华南理工大学电力学院,广州510640 [2]深圳茂硕电气有限公司,深圳518131

出　　处：《电工技术学报》2020年第6期1290-1302,共13页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(51577074)。

摘　　要：该文对临界模式(BCM)混合光伏微型逆变器的特性进行了详细分析。该新型电路拓扑为非隔离虚拟直流母线结构,一方面,继承了升压-反激变换器的低变压器匝比、低漏感量、低电压应力等优点;另一方面,还具有反激变换器的降压特性。利用混合变换器在BCM的自然谐振特性,实现了主开关管的零电压或者谷压软开关,以及整流二极管的零电流软开关。升压-反激变换器还提供了固有的无损吸收电路,使变压器的漏感能量得以利用,并实现了主开关管关断电压尖峰的钳位。上述特性使混合逆变器具有比传统的反激逆变器更小的变压器体积和更高的变换器效率。文中介绍了其工作原理,同时,推导了一种参考电流数学公式,以保证高的并网电流质量。最后,搭建一台240W实验样机,验证了理论分析的正确性和该电路拓扑的性能。The characteristics of the boundary conduction mode(BCM)hybrid-type photovoltaic(PV)micro-inverter are analyzed in detail in this paper.This new topology is a non-isolated pseudo-dc-link structure,which inherits the advantages of low transformer turns ratio,low leakage inductance and low voltage stress of boost-flyback converter,as well as the step-down function of flyback converter.Exploiting the natural resonance of the hybrid-type converter in BCM,the zero-voltage switching(ZVS)or valley switching(VS)of the main switch,and the zero-current switching(ZCS)of the rectifier diodes are achieved.Furthermore,owing to the inherent passive snubber in boost-flyback converter,the leakage energy of transformer is recycled,and the turn-off voltage spike of the main switch is clamped.Because of these characteristics mentioned above,the hybrid-type inverter has smaller transformer volume and higher converter efficiency compared with the conventional flyback inverter.The operation of this topology is described,and the mathematical expression of reference current is derived to guarantee high quality of injected grid current.Finally,a 240W prototype was built to verify the correctness of theoretical analysis and the performance of the topology.

关 键 词：混合微型逆变器 低匝比 低漏感量 低电压应力 软开关 

分 类 号：TM46[电气工程—电器]