一种新型HERIC光伏逆变器漏电流抑制技术研究

A new HERIC PV inverter for restraining the leakage current

针对已有的无变压器光伏逆变器存在共模电压威胁人身安全的问题,在非隔离光伏逆变器(Highly Efficient Reliable Inverter Concept,HERIC)拓扑的基础上,提出了一种新型的箝位型HERIC拓扑。箝位型HERIC拓扑是在逆变器直流输入电容的中点加入了另一个开关管,使整个工作过程中共模电压保持不变。通过仿真发现这一理论是可行的。然后分别搭建HERIC逆变电路和箝位型HERIC逆变电路,通过对比实验和数据分析验证了仿真结果,证明了箝位型HERIC拓扑的有效性和低漏电流特性。

The existing photovohaic inverters without transformer still have common mode voltage ,which is the threat to life. In order to solve this problem, a novel non-isolated photovoltaic inverter called clamped-HERIC topology is proposed, which is based on HERIC topology. This photovoltaic inverter has added a power switch at the point of the DC input capacitance to make the voltage unchanged throughout the course of the work. This theory is feasible by simulation. Then we respectively set up HERIC inverter circuit and the clamped-HERIC inverter circuit. The simulation results are validated by experiments and data analysis. The experiment verifies the validity and low leakage current of the clamped-HERIC topology.