Abstract: The transient characteristics of photovoltaic（PV）power plant are decided by its control system.Based on the typical topology and control strategy of PV power plant,this paper develops an electromechanical transient simulation model for PV power plant.The the low-voltage ride-through characteristics of PV power plant that interact with the transient process of power system are focused.The parameter identification method and the model validation method based on test data are designed.According to the field test data of the PV power plant in a provincial grid in Northwest China,the effectiveness of the proposed model and its validation method is verified.