Analysis on Influence of PI Control Parameters on the Short‐Circuit Current Characteristics of Photovoltaic Power

This study analyzes the short‐circuit current characteristics of photovoltaic (PV) systems when integrated into the electrical grid via power electronic devices. This analysis is crucial as the current output characteristics from the inverter following a fault differ significantly from those of conventional power supplies. Initially, an examination of the control principles of PV inverters is presented, highlighting the structure of these inverters. These control techniques are then used to investigate the PV system's transient behavior during a short‐circuit fault. The transient short‐circuit current output of the photovoltaic power supply is analytically formulated through a comprehensive consideration of the voltage‐loop control and DC bus voltage variation. This study investigates how PI control parameter variations affect the short‐circuit current and its constituent components in photovoltaic power systems. To substantiate the theoretical analysis, a MATLAB/Simulink based simulation model was designed to represent faults in a grid‐connected PV system. A theoretical basis for equipment selection and relay protection configuration in PV‐integrated power grids is established through the results presented in this paper.