Variable pitch control method, device and system and wind generating set

The invention discloses a variable pitch control method, device and system and a wind generating set. The variable pitch control method comprises the steps that the wind direction of incoming flow of the operation environment of the wind generating set is obtained; the running state of the wind generating set and the rotating speed of an impeller of the wind generating set are obtained; acquiring an actual variable pitch control mode of the wind generating set according to the wind direction of the incoming flow; and calculating a pitch angle control instruction of the wind generating set according to the running state and the rotating speed of the impeller. According to the technical scheme, the upper wing faces of the blades are adjusted to be aligned to the prevailing wind direction or the opposite direction of the prevailing wind direction through the 360-degree variable pitch capacity of the blades, the rotating speed of the impeller can be controlled to change within the design range, and the problem of