Research on voltage of distribution networks with distributed photovoltaic system base on probabilistic model

To study the influence on voltage characteristics of distribution network with photovoltaic (PV) system, based on the β-distribution of solar irradiance, the probabilistic distribution model of PV power system is established in the paper. Considering the probabilistic impact of solar radiation on the output of PV power system, the simulation of PV output in three typical weather conditions including low cloudiness days, cloudless days and partly cloudy days is provided and the probabilistic output of PV power system of continuous time sections is attained, which is used to perform the power flow calculation in turn. The calculation result is compared with the power flow calculation result of constant power model. This paper based on a real simulation of distributed PV grid-connected filter in Guangdong, the law of voltage distribution and fluctuation in PV grid-connected distribution networks is demonstrated. The simulation result also shows that the probabilistic model of PV can reflect the randomness and volatility of PV output and power quality issues such as over-limit voltage that PV power brings.