Fan control system

The invention relates to a fan control system comprising a driving motor used for driving a fan to rotate and a control device used for controlling the driving motor according to the position information of the fan, wherein the fan control system further comprises: a three-phase current sampling device used for sampling the three-phase sampling current of the driving motor, a current calculating device used for calculating the given calculating current passing the driving motor and an estimating device used for estimating the position information of the fan according to the three-phase sampling current and the given calculating current. By implementing the fan control system provided by the invention, the angle position and the rotating speed of the fan can be estimated through sampling the current output of one side of an inversion module; therefore, an SVPWM (Space Vector Pulse Width Modulation) control signal for controlling a power switching tube in the inversion module can be obtained; finally the purpos