A method for evaluating the uncertainty of short-circuit current in power system with photovoltaic power generation

Abstract

Short-circuit current of power system with photovoltaic power generation is related to the fault current provided by the photovoltaic power supply. In this paper, based on the analysis of low voltage ride-through uncertain region of photovoltaic power generation, the random model of low voltage off-grid is constructed. Further combining with the system fault information, based on the monte carlo simulation, a probabilistic assessment method of short-circuit current in power system is proposed, which takes into account uncertainty of photovoltaic low voltage ride-through. Finally, an example is given to verify the proposed method. The method in this paper comprehensively considers the random factors of power grid failure and photovoltaic power generation low voltage off-grid, and the short-circuit current result can accurately reflect actual short-circuit current level of the system.