Modeling and Simulation of Single-stage Photovoltaic Power Supply in Double dq Coordinate System

Abstract

In order to study the fault characteristics of a distributed power supply, a photovoltaic power supply model that satisfies grid-connected standards needs to be built first. In this paper, for the single-stage photovoltaic power supply, the mathematical model of the grid-connected inverter in the positive and negative-sequence synchronous rotating coordinate system is firstly set up from its topological structure, and then the expression of the output power of the inverter is deduced. In order to suppress the current distortion caused by voltage asymmetry at the grid point, a control strategy in the dual dq coordinate system is presented by controlling the positive and negative sequence components simultaneously by introducing the control factor K. Finally, simulation analysis was performed on the RTDS real-time digital simulation platform under normal operation and fault conditions. The results prove that the bill of lading-type photovoltaic power supply model meets the distributed photovoltaic power grid-connected standards and can be applied to the analysis and application of engineering projects. Introduction With the rapid development of new energy