Abstract Compared to three-phase three-leg inverter, the control of three-phase four-leg (3P4L) inverter could be decoupled to be able to work with unbalanced load. In recent years, parallel inverter has been widely used in power electronic converter system. If current is out of control in parallel inverters connected with the same input and output buses, circulating current will exist in four legs of parallel 3P4L inverters, which may damage converter seriously. Based on dual closed loop control strategy, output impedance modeling is created in this paper by using small signal modeling method. Thereby, output impedance analysis about the relationships between control loop parameters, main circuit and output impedance is accomplished. Accordingly, a design method is proposed to minimize circulating current. Finally, simulation and experimental results verify the analysis method.
Chen Yihan,Shen Qian,Ren Lei等. Output Impedance Analysis for Circulating Current Minimization of Paralleled Three Phase Four Leg Inverter[J]. Transactions of China Electrotechnical Society, 2016, 31(8): 51-62.
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