适用于分布式光伏接入中压直流配网的三电平零电流开关变换器  

Three-level ZCS Converter Suitable for Distributed Photovoltaic Power Accessing Medium Voltage DC Distribution Network

作　　者：吴健[1] Syed Waqar Azeem 朱小明 夏峰 连建阳[3] 宁光富 WU Jian;SYED Waqar Azeem;ZHU Xiaoming;XIA Feng;LIAN Jianyang;NING Guangfu(State Grid Suzhou Power Supply Company,Suzhou 215004,Jiangsu Province,China;School of Electrical Engineering,Southeast University,Nanjing 210096,Jiangsu Province,China;NARI-Rclays Electric Co.,Ltd.,Nanjing 211106,Jiangsu Province,China)

机构地区：[1]国网苏州供电公司,江苏省苏州市215004 [2]东南大学电气工程学院,江苏省南京市210096 [3]南京南瑞继保电气有限公司,江苏省南京市211106

出　　处：《电网技术》2019年第12期4486-4494,共9页Power System Technology

摘　　要：提出了一种工作于电流断续模式的新型三电平零电流开关变换器,包含一个传统中性点箝位型三电平电路(neutral point clamped three-level circuit,NPC-TLC)和一个简单的辅助控制电路,共6个开关管和2个变压器。通过辅助控制电路的斩波调制可以实现NPC-TLC的零电流开关(zero-current-switching,ZCS)。由于绝大部分的功率是由NPC-TLC传递至负载侧,所以实现其ZCS可以大幅降低本文变换器的开关损耗。文中还重点讨论了辅变压器变比对开关管电流大小的影响,提出了变比优化方法,并基于PLECS软件的仿真模型进行了验证。最后,利用300~1500 V/1500 W的实验平台对理论分析和仿真结果的正确性进行了验证。A novel three-level zero-current-switching(ZCS) converter operating in discontinuous current mode is proposed, which is composed of a traditional neutral point clamped three-level circuit(NPC-TLC) and an auxiliary control circuit, containing 6 switches and 2 transformers. By controlling the auxiliary circuit with pulse width modulation(PWM), ZCS is realized for the basic NPC-TLC delivering most of the power with remarkably reduced switching loss of the converter. The influence of turn ratio of the auxiliary transformer on switch current is discussed, and the parameter design principles are put forward. Simulation verification is performed with PLECS software. Finally, a prototype of 300 V^1500 V/1500 W is built to verify the performance of the proposed converter.

关 键 词：中性点箝位型三电平 零电流开关 

分 类 号：TM721[电气工程—电力系统及自动化]