Reactive voltage control system and method for wind power field of double-fed wind power-generating units

The invention provides a reactive voltage control system and a reactive voltage control method for a wind power field of the double-fed wind power-generating unit. The system comprises dispatching center equipment, a power management module for the wind power field and a plurality of controllers for the double-fed wind power-generating unit, wherein the dispatching center equipment is used for calculating a reactive power set value of the wind power field according to real-time monitored voltage and active power at a control point of the wind power field and a reference voltage; the power management module for the wind power field is used for distributing the reactive power set value in the wind power field; and the plurality of controllers for the double-fed wind power-generating unit are used for controlling corresponding double-fed wind power-generating unit to perform reactive power compensation according to the reactive voltage value of the double-fed wind power-generating unit distributed by the power management module for the wind power field. According to the reactive voltage control system and the reactive voltage control method for the wind power field of the double-fed wind power-generating unit, the reactive output capability of the double-fed wind power-generating unit can be fully exerted, the cost of reactive power compensation equipment of the wind power field is reduced, and the purpose of controlling the voltage of the wind power field is fulfilled by mutual coordination and control of the dispatching center equipment, the power management module for the wind power field and the plurality of controllers for the double-fed wind power-generating unit.