Performance evaluation of an optimized simplified nonlinear active disturbance rejection controller for rotor current control of DFIG-based wind energy system

Abstract

A comparative analysis of three distinct control strategies for rotor current regulation in a doubly fed induction generator (DFIG)-based wind energy system (WES) is introduced in this paper. Due to the inherent nonlinear dynamics of DFIG, which increase the system's complexity, conventional proportional-integral (PI) controllers often face limitations in maintaining optimal performance. To address these challenges, an optimized simplified nonlinear active disturbance rejection (SNADR) control strategy, enhanced through the Particle Swarm Optimization (PSO) algorithm for parameter tuning, is proposed. This research fills a critical gap in the selection of parameters for SNADR controllers, which are usually tuned by trial and error. The SNADR controller's performance is evaluated against traditional PI and linear active disturbance rejection (LADR) controllers through MATLAB simulations under different operating conditions. The PSO-optimized SNADR controller demonstrates several key advantages such as superior accuracy in tracking rotor current set points under constant wind speeds, robust performance despite wind speed fluctuations, and enhanced resilience against parameter uncertainties by compensating for system nonlinearities. The comparative analysis demonstrates that the SNADR controller achieves faster dynamic response, reduced overshoot, and minimized steady-state error, making it a highly effective solution for improving the performance and reliability of DFIG-WES.