Study on reactive voltage regulation and optimal control strategy of PV power station considering energy storage system

Most of the photovoltaic (PV) power plants in operation are equipped with a certain proportion of Static VAR Generator (SVG). The reactive power and voltage control system in PV power station achieves the control objectives of the dispatching mechanism by controlling SVG, without considering the reactive power and voltage regulation ability of the inverters themselves. To better exert the reactive power and voltage support ability of the PV inverters, reduce the SVG system investment and later O&M costs. It is necessary to introduce new voltage regulation methods. This paper focused on a hybrid reactive voltage regulation, method and control strategy based on energy storage system and PV inverters. By combine the good response characteristics of energy storage battery and optimizing the configuration and coordination control, it can not only respond to the second-level steady-state reactive power demand of PV power station, but also respond to the millisecond-level reactive power demand. The ability of second-order transient voltage fluctuation was verified by the example of Luneng Haixi Demonstration Project, which satisfies the power system requirements for ability and speed of reactive power regulation, and plays a role in replacing SVG to a certain extent.