Calibration of Distributed PV Setting Calculation Model and Simulation Calculation Model Based on Short-Circuit Test of Distribution Network

Large-scale distributed photovoltaic access to the distribution network has brought unprecedented challenges to traditional relay protection. According to relevant standards, distributed photovoltaic should have a certain low voltage crossing ability during the grid fault transient, and the short-circuit current presents the characteristics of “phase Angle controllable and amplitude limited”, which is greatly different from the traditional power supply. Therefore, it is necessary to carry out relevant research on the principle adaptability and fixed value adaptability of large-scale distributed PV to traditional relay protection after grid-connected. Relevant analysis should rely on accurate simulation calculation model and setting calculation model. In this paper, based on PSCAD simulation platform and setting calculation platform, the distributed photovoltaic grid-connected simulation calculation model and setting calculation model are established respectively. Based on the actual recorded wave data of two distribution network short-circuit tests, the two models are calibrated. The results show that the accuracy of the simulation calculation model is less than 2%, and the setting calculation model is less than 10%, which meets the needs of engineering calculation, and lays a model foundation for the next large-scale distributed photovoltaic grid-connection research.