This paper describes the presentation of a stepper motor in the pitch control system to regulate frequency. The controller sense the frequency deviation. If the frequency deviation is positive the stepper motor will recommend the motor to pitch the turbine blade slightly away from wind pressure. Similarly if the frequency deviation is negative the stepper motor will recommend the motor to pitch the turbine blade slightly towards wind pressure. The blade pitching is performed by another motor. The frequency controlled by conventional hydraulic mean is costly complex and quite slow in response. They consume enough time during big load changes. In this research a stepper motor is being used for frequency control. A stepper motor is economical capable of fast action and easy to control. The position of the stepper motor is controlled by a PI Proportional Integral controller. Thus a proposed frequency control system incorporating a stepper motor in pitch control system is modeled, designed and simulated in Matlab/ Simulink. The frequency control through stepper motor improves the Transient and steady state performances are enhanced and moreover it reduces frequency spikes.
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