According to the national standard

the high-power photovoltaic gird-connected inverter should have the zero voltage ride-through(ZVRT)ability of avoiding automatic off-grid phenomenon under the condition of low voltage

which will affect the stable operation of power system. Based on an analysis of the standard about ZVRT of photovoltaic grid-connected inverter

some key technologies including the separation of positive from negative sequence of grid voltage

phase-lock loop(PLL)

the control strategy of active/reactive current

the control strategy of inverter under the condition of unbalanced grid voltage

etc are discussed. In addition

the leading phase compensation for the feed-forward component of grid voltage is proposed and introduced into the current loop of control system to limit the current overshoot during the transients of ZVRT. The effectiveness of the proposed ZVRT control strategy is verified by simulation on RTDS and experimental results of a 500 kW prototype.