Study on the influence of grid connected capacity difference of photovoltaic power generation on power grid performance

Abstract

Due to the integration of photovoltaic power generation system, the structure of traditional distribution network will change, and then the grid system after grid connection is in an abnormal working state. If relevant measures are not taken, the operation quality of grid cannot be guaranteed. Therefore, based on the working principle of photovoltaic cells, this paper studies its equivalent model and output characteristics, builds a single-stage three-phase photovoltaic grid connected system on PSCAD platform, verifies the correctness of power control strategy, analyses the impact of photovoltaic grid connection on distribution network loss and voltage, establishes a 33 node model for example analysis, and simulates the grid connection of photovoltaic power generation system under different capacities and locations for many times, the calculation example of determining the location and capacity of photovoltaic grid connected power generation system is analysed, and a multi-objective mathematical model is proposed based on DG cost and active power loss. The installation quantity, capacity and location of DG are deeply studied, and the optimization function is carried out based on genetic algorithm, so as to realize the minimum impact condition of photovoltaic grid connected power generation on power quality of distribution network, and then realize the optimal configuration of photovoltaic power generation system.