With the rapid growth of distributed photovoltaic power generation in China, the contradiction between the large number of distributed PV access and distribution capacity of distribution network has become increasingly prominent. How to improve the grid-connected characteristics of distributed PV system to adapt to the current distribution network environment is Need to solve the problem. Based on this, a distributed PV grid-based strategy based on instantaneous power control is proposed. Through the control of the instantaneous power of the PV system, the PV system realizes the real-time fast power regulation according to the state of the distribution network. Based on the simulation example of PV grid-connected system, this simulation strategy is used to simulate the two different reactive power states of the distribution network. The theoretical analysis and simulation results show the effectiveness of the grid-connected control strategy.