一种实用的光伏逆变器高电压穿越方案

Applied Method of High Voltage Ride-through for Photovoltaic Inverter

针对光伏逆变器在高电压穿越期间可能出现过调制问题,本文分析了电网电压暂升期间的高电压穿越技术,通过判断直流电压大小来确定当前系统是否出现过调制,分析了可能出现的两种过调制情况。为了抑制过调制问题,给出了一种抬升直流侧电压的方法,搭建了高电压穿越实验平台进行了实验。实验结果表明,该方法有效抑制了过调制,从而提高了系统的可控裕度和稳定性。

In view of the over modulation problems that may occur during the high voltage crossing of the photovoltaic inverter, the high voltage crossing technology of power grid voltage swell is analyzed. Determine whether the current system is over modulation by judging the size of the DC voltage. Two kinds of possible over modulation conditions are analyzed. In order to suppress the over modulation problem, a method of lifting the DC side voltage is given. A high voltage crossing experiment platform was set up to carry out the experiment. The experimental results show that the method effectively suppress the over modulation and improves the controllability margin and stability of the system.