光伏直流汇集关键电力电子设备技术现状分析

Technology Status Analysis of Key Power Electronic Devices for Photovoltaic DC-Connected Power Systems

光伏直流汇集与交流汇集相比,发电效率高,所需变流器级数少,且输电过程损耗小,输电容量大。但直流汇集的升压技术以及工程应用不及交流汇集成熟。通过分析光伏直流汇集所需的高升压比DC/DC变换器的拓扑结构,高频变压器的容量与工作频率,直流断路器的电压、电流及关断时间,分析了光伏直流汇集的工程应用可行性。

Compared with the photovoltaic AC-connected power system,the photovoltaic DC-connected system has advantages of higher efficiency,less converters’ classes,smaller transmission loss,and larger transmission capacity.However,technologies and engineering applications of the photovoltaic DC-connected power system are not as mature as the AC system.Topologies of high boost ratio DC/DC converters,capacity and working frequency of high-frequency transformers,and voltage,current and turn-off time of DC circuit breakers are analyzed in this paper to illustrate the engineering application feasibility of photovoltaic DCconnected power systems.