Research of Restraining Harmonic Circulating Current of Paralleled Inverters System

In order to solve the problem of harmonic circulation current in paralleled inverters system,a method of restraining harmonic circulating current was proposed based on analysis of mathematic model of single inverter with harmonic disturbance and produced principle of harmonic circulating current in paralleled inverters system,in which dual-ring control mode of current and voltage was used for single inverter of paralleled inverters system and coupling inductances were added to output ends of inverters.The theoretical analysis and simulation result verified the validity of the method.