Disclosed is a wind power plant power controller. The power controller comprises a central processing unit, a power supply module, a power grid detection module, a communication module, an abnormality processing module, an active frequency control module and a reactive voltage control module, wherein the central processing unit is connected with the power supply module, the power grid detection module, the communication module, the abnormality processing module, the active frequency control module and the reactive voltage control module separately; the wind power plant power controller is mounted in a booster station, and the power controller, a wind turbine, a reactive compensation apparatus, a booster station monitoring system, a wind power plant monitoring (SCADA) system and a dispatching center main station form a wind power plant power control system network; and the wind power plant power controller receives active and voltage instructions from the dispatching center main station or underground in a communication way, performs unified cooperative control on the wind turbine, the reactive compensation apparatus, and a transformer gap gear, performs active power and reactive power regulation, and realizes stable control on frequencies and voltages.