Achieving optimum tip-speed-ratio of a two-mass wind turbine system

Abstract

This paper proposes a three term PID controller to achieve optimum tip-speed ratio of a variable speed fixed pitch two-mass wind turbine system. The main advantage of the method is the functional simplicity and the robust performance in a wide range of operating condition. The objective is achieved by maintaining optimum speed of the rotor via adjusting the restoring generator torque. Hence, PID controller is formulated and employed into the generator side of wind turbine system to achieve the asymptotic tracking of the rotor speed. To validate the effectiveness of the proposed method, a simulation in MATLAB/SIMULINK® is carried out. The result shows that the speed tracking can be achieved by using PID. However, the speed response shows inadequate control performance with less efficacy as the closed-loop system incur large initial speed overshoot. This phenomena shows the shortcomings of conventional PID and hence, open up new research awareness on solving this problem.