Stability Analysis of Microgrid under Inductive Network Impedance

Abstract

Due to a certain degree of inductive impedance the power grid, it can not be regarded as an ideal voltage The impedance will affect the control performance of the inverter, and even lead to the instability of the system, which makes the output current of the inverter can not meet the network access standard. The existence of local load will also affect the analysis of system stability to a certain extent. Therefore, the control model of PV grid connected inverter considering local load and grid impedance is established, including grid impedance and load at common coupling point. The stability margin of the system is described more accurately by impedance analysis method. Based on this model, the tuning of system control parameters under different grid impedances is studied to improve the stability of photovoltaic grid connected control system. The effectiveness of parameter tuning is verified by simulation.