Application of multi stage fuzzy logic control for Load Frequency Control of an isolated wind diesel hybrid power system

This paper presents an analysis of multi stage fuzzy logic control application for load frequency control of isolated wind-diesel hybrid power system. Due to the sudden load changes and intermittent wind power, large frequency fluctuation problem can occur. An effective controller for stabilizing frequency oscillations and maintaining the system frequency within acceptable range is significantly required. The load frequency control (LFC) deviates the frequency deviation and maintains dynamic performance of the system. As fuzzy logic control approach can be easily implemented in practical systems, the fuzzy logic control has been applied to design LFC system. In this paper, multi stage Fuzzy logic PID controller is proposed for Load Frequency Control (LFC) of an isolated wind-diesel hybrid power system. Simulations are performed for this hybrid system with the proposed multi stage Fuzzy Logic PID controller, conventional PI controller and Fuzzy logic controller with different load disturbances and wind input disturbances. The performance of the proposed approach is verified from simulations and comparisons. Simulation results explicitly show that the performance of the proposed multi stage Fuzzy Logic PID Controller is superior to the conventional PI controller and Fuzzy logic controller in terms of overshoot, settling time and steady state error against various load changes and variations of wind inputs.