Early Warning Method of Substation Heavy and Overload of Distributed Photovoltaic Access to Distribution Network

The high proportion of distributed photovoltaic access brings a series of problems to the distribution network, such as overload of distribution transformer, power flow backflow and high terminal voltage. Distribution network photovoltaic consumption assessment and equipment heavy or overload of distributed photovoltaic access have become important factors restricting the development of distributed photovoltaic. The output simultaneity coefficient of the distributed photovoltaic in the output period is analyzed in this paper first. The probability that the average value of the photovoltaic output simultaneity coefficient in the analysis period is greater than the average value of the output coefficient in the month is calculated. Based on the development situation of distributed photovoltaic and the load of the regional power grid in the future, the DC capacity and the capacity ratio of distributed photovoltaic, the value range of component capacity and critical development capacity of distributed photovoltaic in the target year under different scenarios are calculated. Then, the load rate of the substation in different scenarios is analyzed. The development efficiency index of the distributed photovoltaic in regional power grid is proposed to evaluate its development efficiency. Finally, a regional power grid substation is used to verify the effectiveness and adaptability of the proposed method.