Control of Wind Turbine for Variable Speed Based on Fuzzy-PID Controller

Abstract

Nyala is one of the most suitable areas in Sudan for building wind energy conversion system. This system could be linked with Nyala electrical grid without expensive cost because it is near to the electrical local grid. The permanent changes of wind speed with no stablemode generate different amplitude and frequency voltages which differ from Nyala electrical grid utility parameters. This requires good and suitable controller to facilitate the link process or direct connection to the load. This paper proposes a fuzzy-PID controller as maximum power point tracker (MPPT) to track the maximum power available from the wind energy conversion system (WECS) and to obtain AC voltage with constant amplitude and frequency. The maximum power is obtained based on the rotor speed of the wind turbine which represent in error between actual rotor speed of PMSG and estimated value of rotor speed depend on values of DC current and voltage at the terminal of boost-converter and parameters of PMSG. The error of rotor speed is given as input to the fuzzy-PID controller that controls the duty cycle of pulse width modulation (PWM) generator and its output is connected to the boost converter. The proper wind turbine with its generator was chosen depending on parameters of probability density function (pdf), called Wiebull Function. To validate the correctness and effectiveness of the proposed system, it is simulated with MATLAB/SIMULINK model. The simulation results show the good performance of the proposed control scheme.