Abstract：This paper proposes an improved load sharing controller for parallel connected inverters. The voltage and current dual-loop proportional control method is designed to implement resistive output impedance, and the Q-ω and P-V droop method is adopted. An adaptive virtual resistor is added to regulate the magnitude of the output impedance according to the requirements of active power sharing, which weakens the coupling between the current sharing control and output voltage amplitudes of paralleled inverters. The feedforward of the reference voltage is employed to increase the gain of the system, and the RMS (root-mean-square) loop is adopted to maintain small steady-state error of output voltage. Experimental results demonstrate the validity of the proposed scheme.
林燎源, 林钊, 刘伟, 马皓. 基于阻性下垂的逆变器无线并联均流控制[J]. 电工技术学报, 2016, 31(8): 43-50.
Lin Liaoyuan, Lin Zhao, Liu Wei, Ma Hao. Wireless Current Sharing Scheme for Parallel Operation of Inverters Using Resistive Output Impedance. Transactions of China Electrotechnical Society, 2016, 31(8): 43-50.
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