A ZVRT Control Method for Controlling Output Current of Inverter

In this paper, a control method for zero voltage ride-through of inverter output current is proposed for the problem of off-grid of photovoltaic power station in single-phase drop of grid voltage. The method gives a reference value of the current positive and negative sequence according to the requirement of the zero-voltage traversing standard during the voltage drop, thereby avoiding an overcurrent problem that may occur during the fault of the inverter output current, and ensures the stability of the DC side voltage during the voltage drop. At the same time, this paper uses a second-order complex filter on the extraction of positive and negative sequence components to improve the extraction efficiency of positive and negative sequence fundamental waves. Finally, a photovoltaic grid-connected model is built on the MATLAB/Simulink platform to verify its effectiveness.