Mathematical model of variable speed pitch regulated turbine in a wind energy conversion system

Abstract

Pitch control of wind turbine in a wind energy conversion system involves the change of the rotor blade pitch angle along the rotor axis. Most compa-nies are faced with the challenge of maintaining a steady and optimal power supply. The control involves the pitch angle of the blades, wind speed and the angular velocity of the turbine. The main objective is to optimize wind energy capture. This is done by a close-loop control through modelling and simulation undertaken and implemented in MATLAB/SIMULINK simulation environment using the power coeficient equation which relates the pitch an-gle and the power output to optimize energy capture. Results of the variable speed and pitch control at steady tip speed ratio are obtained graphically. In conclusion, the simulation shows that only small changes of pitch angle are re-quired to maintain the power output at rated power.