Current Sharing Method for Parallel Inverters Based Impedance Matching Mode

The inverter current sharing is the main problem to be solved in AC power supply system with inverters in parallel mode.Dynamic inverter current and static current sharing are equally important,but existing methods can not fundamentally solve the problem of dynamic current sharing.In addition,inhibition of the DC circulation in the inverter parallel system and the DC offset of the output voltage are also the technical problems to be solved.For the above reasons,a parallel control scheme was proposed based on virtual resistor matching mode.The inverter was designed as a given reference voltage source and a virtual resistance in series.The control target was achieved by the control of the value of virtual resistance.The designed system has good dynamic and static current sharing effect and can completely inhibit the DC circulation.Furthermore,in any load condition,the output voltage has not DC offset.Simulation and experimental results show the effectiveness of the proposed control scheme.