Abstract：In recent years,the transformerless photovoltaic inverter has attracted more and more attentions in academic and industry for its light weight,small size,and high efficiency.But its leakage current is one of the most important issues.A new three-phase HERIC topology is proposed based on the single-phase one in this paper to solve the problem.The operation principle and the common mode model is presented.The effect of the modulation strategies on the common mode voltage (CMV) is discussed.A new modulation scheme based on Boolean logic operation is proposed to solve the problems of common mode voltage fluctuation.Consequently,the leakage current is significantly reduced.The simulation of the proposed solution is carried out in Matlab,and the experimental tests are implemented on a down-scaled hardware prototype.The results verify the effectiveness of the proposed solution.
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2016, Vol. 31 
