Active Power Control of Wind Turbine Considering Pitch Saturation

With the increasing penetration of wind power, wind turbines (WTs) have to be equipped with the capacity for active power control (APC) in response to the power commands from the grid. In order to reduce the action of the pitch actuator, the existing research mostly adopts the technical route of utilizing the rotor speed variation to replace the pitch action. Usually, the rotor speed is limited by the proportional-integral (PI) control at the speed boundaries, which has neglected the influence of the pitch control on the rotor speed variation within the speed range. Due to the rate limit of the pitch actuator, it exists that the pitch control is saturated, affecting the APC's performance. Hence, the improved APC method based on anti-saturation pitch control is proposed in this paper. The results show that the proposed method can alleviate the saturation of the pitch control, reduce the pitch action and the electrical power drop. The APC's performance has improved.