A new control approach to improve the dynamic performance and ride through capability of PMSG wind energy system

Abstract

The increasing penetration of wind power into the modern power system forces many countries to adopt and revise grid codes for wind farms. The latest grid codes demand the wind energy systems to remain online during grid disturbances to meet the Low Voltage Ride-Through Capability (LVRT). The disconnection of the grid connected wind farm under abnormal grid disturbances significantly impacts the stability of the grid system. This paper proposes the robust active disturbance rejection control for permanent magnet synchronous generator (PMSG) based wind energy systems to enhance the dynamic performance and ride through capability under abnormal grid disturbances. The proposed approach is applied to the machine and grid side converter of PMSG to improve its ride through capability in compliance with the grid codes. Besides external grid disturbances, the proposed approach also considers the internal disturbances such as random parameter variations, parameter uncertainties, and cross-coupling terms to improve the dynamic performance of the wind energy system. The proposed approach is particularly effective in real-time estimation and compensation of the internal and external disturbances. The simulation results are performed in Matlab/Simulink to support the theoretical considerations, demonstrating the potential contributions of the proposed control strategy. The superiority of the proposed control strategy to improve the LVRT potentiality for the grid-connected PMSG wind energy system is verified by comparing with the traditional vector PI control scheme.