Control method for voltage and reactive power control system

The invention discloses a control method for a voltage and reactive power control system. The control method comprises the steps that before the voltage and reactive power control system reads the voltage of a sampling network system, the communication state between the voltage and reactive power control system and a voltage sampling device is judged, and when it is judged that the voltage and reactive power control system and the voltage sampling device are in communication, the voltage of the network system is collected, and the working area of the voltage of the network system is distinguished. According to the method, before thee working area of the voltage of the normal network system is judged, the communication detection and judging processes for the voltage and reactive power control system and the voltage sampling device are conducted, the problem that communication interruption of the voltage sampling device causes false adjustment of the voltage and reactive power control system is avoided, normal actions of the voltage and reactive power control system are guaranteed, and safe operation of a power grid is guaranteed.