A Calculation Method of Maximum Short-circuit Capacity for Distribution Network with Distributed Photovoltaic Power Supply

In this paper, a formula for estimating the distribution network's maximum short-circuit capacity while taking distributed photovoltaic power access into account is presented. Firstly, without considering the influence of photovoltaic power station access on the distribution network, the voltage of each point in the distribution network and the short-circuit current at the fault point are calculated only in the case of three-phase short-circuit at a certain point in the distribution network. Then, considering the phase Angle at the short circuit moment, the short circuit current provided by each photovoltaic power station is calculated respectively, and added with the short circuit current calculated above, to obtain the calculation results of short circuit current and short circuit capacity. Finally, taking a small power distribution network connected to PV in Anhui Province, China as an example, the short-circuit capacity of the power distribution network under different fault conditions is calculated. The results show that the method is simple and fast, and the obtained data is in agreement with the actual data.