【摘要】 近年来,非隔离型光伏逆变器以其重量轻、体积小、效率高的特点得到了学术界与工业界的广泛关注。其中漏电流是亟待解决的关键问题之一。在单相Heric电路基础上,提出三相Heric拓扑解决漏电流问题。分析了电路工作原理,建立了系统共模模型,探讨了不同调制策略对系统共模电压的影响,并提出基于布尔逻辑运算的调制策略解决共模波动问题,实现了系统共模电压恒定,从而使漏电流得到有效抑制。利用Matlab对提出方案进行了仿真研究,并在实验样机上进行了验证,实验结果证明了提出方案的有效性。更多还原

【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.更多还原