Abstract：The conventional microsource wireless droop control base on “power-voltage-current” close loop is widely used. The power sharing performance of this method is significantly affected by the resistive line impedance. This paper analyzes the effectiveness of two existing solutions: the adjustment method by choosing proper control parameters has limited regulating range, which means a poor performance; the virtual impedance control method has a wide range. But it has the problem of voltage sag, this paper provides an improved method with no Q-V power close loop. This method simulates the virtual impedance as the virtual synchronous generator inductance; uses the virtual impedance voltage to realize the microsource Q-V voltage droop characteristic, which can save the microsource voltage sag amplitude. Finally, simulation results and experimental results on the parallel inverter are provided to prove the performance of this new control method.
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2014, Vol. 29 
