Differential Transformation Based Adaptive Switching Control of Wind Turbines

With the increasing penetration of wind generation and retirement of conventional coal-fired power plants, system frequency response may become inadequate under disturbances. Wind turbine generators can be switched to a frequency support mode once frequency deviation exceeds a preset deadband, not adapt to the disturbance. This paper proposes a new control strategy for wind turbine generators to adaptively switch between the normal operation mode and frequency support mode. The idea is to predict the safety of a frequency response in real time using a differential transformation method and activate a frequency support mode only when necessary. This control strategy effectively avoids unnecessary switches with the conventional deadband method but still ensure adequate frequency responses to disturbances.