Coordination Control Strategy of Distribution Grid Voltage Based on Adjustable Resources in Substation Area

A voltage coordination control strategy based on adjustable resources in power distribution grid is presented for improving the precision of voltage deviation control in power distribution grid. Firstly, the mechanism of voltage change in distribution grid is analyzed, and the relation between reactive power and PCC voltage change is quantified. Then, the characteristics of photovoltaic(PV) output and user load are analyzed, and the line voltage deviation curve is obtained, which can be used to determine the installation location and capacity of the var compensation equipment. On this basis, the PV output is predicted according to different time scales, and the reactive power of the adjustable resources in the station is allocated to ensure the voltage deviation requirements of the bus and nodal points in the station area with the objective of voltage deviation and user economy. An example shows that the strategy used in this paper has higher precision than traditional voltage regulation. By introducing traditional reactive power compensation devices into the station and invoking the PV reactive power balance, this strategy reduces the installation amount of the station reactive power compensation devices, and improves the precision of voltage deviation correction according to the relation between reactive power and PCC voltage variation.