Control Scheme of Hybrid Wind-Diesel System with SMES Using NSGA-II

Abstract

Robust control approach of hybrid wind-diesel power system is proposed in this paper. PID (proportional integral derivative) controller is designed in the blade pitch system of wind turbine to improve the system dynamic performance. Furthermore, to minimize the system oscillations, SMES (super-conducting magnetic energy storage) with first order lead-lag controller is implemented to supply and absorb active power quickly trying to reach power generation/demand balance and thereby control system frequency. Minimization of frequency and wind output power deviations are considered as two objective functions for the PID controller of wind turbine. Also, mitigating frequency and diesel output power deviations are presented as two objective functions of the lead-lag controller of SMES. NSGA-II (modified version of non-dominated sorting genetic algorithm) is used to tune the controllers' parameters to get an optimal response. The effectiveness and robustness of the proposed control technique are investigated under different operating conditions using Matlab environment. The simulation results confirm the ability of the controllers to damp all frequency and output powers fluctuations and enhance the stability and reliability of the hybrid power system.