Photovoltaic (PV) power station connection may affect the distribution network current protection. Firstly, the short circuit calculation model of PV power station under the conventional control strategy is discussed. And based on the equivalent circuit of typical distribution network with the connection of the PV power station, theoretical analysis are conducted from three aspects of the position of the short circuit, the capacity and connection position of PV power station. Finally, taking 35kV typical distribution network as an example, the correctness of the theoretical analysis is verified by simulation. The research results have certain guiding significance for the connection of PV power station.