六开关光伏并网逆变器共模漏电流抑制方法

Leakage Current Suppression Method with a Novel Six-switch Photovoltaic Grid-connected Inverter

为了解决非隔离型光伏发电系统中的漏电流问题,提出一种六开关拓扑及控制方法。采用开关旁路电感策略,解决了传统六开关光伏并网逆变器共模电压受电感值匹配因素影响的问题,保证光伏系统寄生电容两端电压不含高频分量。通过理论分析和仿真研究的方法,对提出的六开关拓扑及控制进行了验证。研究结果表明,所提出的拓扑及控制方法可以实现漏电流的有效抑制。

In order to solve the problem of the leakage current in non-isolated photovoltaic systems,a novel six-switch topology and control strategy is proposed.The inductor-bypass strategy has solved the common mode voltage limitation of the conventional six-switch topology in the case of unmatched inductance.And the stray capacitor voltage of the non-isolated photovoltaic system is free from high frequency ripples.Theoretical analysis and simulation are carried out to verify the proposed topology and its control strategy.Results show that leakage current suppression can be achieved with the proposed solution.