全MOSFET型全桥非隔离光伏并网逆变器  

A Full Bridge Transformerless Photovoltaic Grid-connected Inverter with All MOSFET

作　　者：过亮 肖华锋[2] 兰科[2] 王彤 

机构地区：[1]南京南瑞集团公司,南京211106 [2]东南大学电气工程学院,南京210096

出　　处：《科学技术与工程》2016年第5期156-160,共5页Science Technology and Engineering

基　　金：2014年国家电网公司科技项目(524608140017)资助

摘　　要：带交流旁路环节的非隔离型单极性SPWM全桥光伏并网逆变器可以在不增加导通损耗的前提下改善共模特性。为了进一步消除共模电压引起的漏电流,可以采用箝位技术实现高频共模电压为恒值。提出一种改进型全桥电路结构和调制方式,在续流模态提供了交流旁路环节和二极管无源箝位,避免了有源箝位支路的死区对箝位效果的影响。在桥臂和续流回路中采用Si C-MOSFET器件可消除桥臂二极管反向恢复问题和降低电流回路阻抗,可以大幅提高变换效率。详细分析了新型逆变器结构和准单极性SPWM调制的差模和共模特性,并通过一台50 k Hz/3 k W实验样机对比验证了新型拓扑的性能。The transformerlsee photovohaic （PV） unipolar SPWM full-bridge inverter with ac bypass brings low conduction loss and improves common-mode performance. In order to eliminate leakage current induced by com- mon-voltage, the clamping technology is adopted to clamp common-voltage to a constant value. An improved invert- er topology and modulation strategy has been proposed, two independence freewheeling paths and two diodes are added into the ac side of full bridge inverter. And then, the SiC-IGBT is adopted in the inverter to eliminate the re- verse recovery problem. As a result, the efficiency can be significantly improved. The operation mode, differential- mode and common-mode characteristics of the proposed inverter are analyzed in detail. Finally, the performance of the proposed topology is verified by a prototype inverter rated at 3 kW and 50 kHz.

关 键 词：全桥逆变器 准单极性 共模电压 箝位 

分 类 号：TM464[电气工程—电器]