Research on transmission and distribution network reactive power/voltage coordinated control technology of large receiving-end urban power grid

In recent years, as distributed generation, new loads and new FACTS devices widely access, high sensitive power users increasing, the existing automatic voltage control (AVC) technology of urban power grid have been unable to meet the new requirements under the new situation on the control objectives, control strategy and control means. In the aspect of control objectives, it only meets the reactive power balance of partition and voltage qualified rate of control bus, doesn´t effectively reflect the user-end need of high quality power supply, therefore it is difficult to achieve the global optimal. In the aspect of voltage control means, it have not covered the Reactive Power device of distribution and demand side; In the aspect of voltage control strategy, it focuses on the transmission network optimization, and the control strategy applicable to the special structure features of distribution grid has not been established. Therefore, this article puts forward the coordinated control system that based on the existing three-level voltage control, expand reactive voltage control of distribution and demand side, and fully meet the requirements of the user-end static and dynamic voltage quality. Through perfectly choosing reasonable coordination variables, it finally constructs the entire network reactive power/voltage control system, which coordinates the transmission and distribution network control with multi-objective, multi-level, discrete and continuous coordination control.