Abstract：On the basis of analyzing parallel multi-inverters’ power distribution mechanism, this paper proposes a low-delay robust droop control method.Through redesigning the equivalent output impedance of the inverters as the pure resistance, it can decouple the active/reactive powers in the droop controller.Then, by constructing integrator 1/s in active power control, the Q-f/P-U′ droop controller and U′ recovery mechanism is proposed to improve the robust of the output power against the line impedance and equivalent output impedance.Thus the parallel multi-inverters can share the load power with regard to the ratio of their rated capacities accurately.In additional, considering the phase characteristic of equivalent output impedance is unchanged in this method, it does not need to design the equivalent output impedance again and reduces the design difficulty.Moreover, the system dynamic can be improved by the least-mean-square adaptive algorithm, which reduces the control hysteresis of the power calculation.Finally, simulation and experimental results verify the validity of the proposed strategy.
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2016, Vol. 31 
