Aiming at the problem of rapid and frequent fluctuation of grid voltage under high proportion wind power interconnection

a multi-time scale optimal control method of reactive power and voltage based on MPC（Model Predictive Control） is proposed. Based on the day-ahead optimal arrangement of discrete reactive power compensation equipment

the voltage is controlled by continuous reactive power compensation equipment within the intra-day time scale

which adopts the idea of rolling optimization and correcting control based on MPC. Firstly

the grid voltage foresting model based on sensitivity is established to forecast the voltage states at multiple future moments. Then

the intra-day rolling optimization model is built with the minimum expected voltage control deviation at multiple future moments as its optimization objective

based on which

the reactive power control planning of continuous reactive power compensation equipment is obtained. The intra-day MPC of reactive power and voltage is realized by correcting the voltage control deviation. Finally

a wind power cluster system in "three northern"regions of China is taken as the example

whose simulative results verify the feasibility and effectiveness of the proposed method in improving the voltage control level by comparing with the traditional voltage control method.