Starting from the safe operation and economic benefit of the incremental distribution network and facing problems caused by high-permeability distributed photovoltaic access distribution networks, this paper puts forward a time decoupled dynamic extended reactive power optimization model, which aims to minimize the cost of power grid loss, capacitor and transformer regulation cost, and energy storage adjustment cost. Based on the traditional reactive power optimization model, the new model increases the power adjustment ability of energy storage and the reactive power adjustment ability of photovoltaic, decoupling dynamic reactive power optimization into multi-period static reactive power optimization. It uses the disaster genetic algorithm to obtain the reactive power optimization in incremental distribution network with photovoltaic-energy storage hybrid system and compare with other optimization method. Results show that proposed time decoupled dynamic extended reactive power optimization method can improve the effect of reactive optimization of incremental distribution network, reduce power grid loss and lower equipment adjusting cost, and consider the safety of power grid voltage operation. This work is supported by Natural Science Foundation of Guangdong Province (No. 2017A030313304) and National Natural Science Foundation of China (No. 51777077).