Abstract In order to solve the problem of the leakage current in three-phase photovoltaic(PV) inverter systems,a new solution of the leakage current reduction is proposed with the three-phase four-leg PV inverter.The common mode loop model of the transformerless four-leg PV inverter is presented.The effect of different factors and variables on the leakage current is discussed.A new modulation strategy based on Boolean logic function is then proposed to ensure the constant common-mode voltage.And thus the leakage current can be significantly suppressed.Finally the proposed modulation is implemented on the TMS320F28335DSP+XC3S400FPGA digital control hardware platform.And the performance is also presented by comparison with the conventional modulation methods.The experiment results verify the effectiveness of the proposed modulation strategy.
Guo Xiaoqiang,He Ran,Jian Jiamin等. Leakage Current Reduction for Three-Phase Four-Leg Photovoltaic Inverter[J]. Transactions of China Electrotechnical Society, 2016, 31(19): 66-73.
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2016, Vol. 31 
