摘要
共模电流抑制是非隔离型光伏并网系统中需要解决的一个关键问题,各国都对共模电流做出了相关规定。当共模电流超过规定值时,系统必须在规定时间内与电网断开。针对光伏并网系统中存在共模电流的问题,建立了系统共模等效模型,在此基础上分析共模电流产生的机理,探讨不同调制策略对抑制共模电流的影响,并提出一种新型的能够有效抑制共模电流的逆变器拓扑结构,分析它的工作原理和特点,最后通过仿真分析验证了该拓扑的正确性。
Common-mode current suppression is a key issue to be solved in transformerless grid-connected photovoltaic systems, for which most nations have made relevant regulations. When common-mode current exceeds the prescribed value, the system needs to disconnect with the grid in certain amount of time. To deal with existing problems in trans-formerless grid-connected photovoltaic systems, this paper builds the common-mode equivalent model. Based on this model, the paper analyzes the mechanism the common-mode current is generated, discusses how different modulation strategies have impacts on it, and proposes a novel inverter topology capable of effectively suppressing the current. The mechanism and features of this topology are analyzed and proven by simulation results.
出处
《电测与仪表》
北大核心
2014年第5期36-40,共5页
Electrical Measurement & Instrumentation
关键词
共模电流
光伏并网
非隔离
逆变器
H6
H6
common-mode current
grid-connected photovoltaic
transformerless
inverter
