Research on reactive voltage control strategy for substations connected to photovoltaic systems

Abstract

The reactive voltage control of conventional substations is mainly realized by adjusting the switching of capacitors or reactors and changing the transformer ratio, which can only be controlled discretely. The PV inverter can carry out continuous reactive power control, and the reactive voltage control strategy of the conventional substation does not consider the reactive power control of the PV. In this paper, the nine-zone diagram control strategy of the traditional substation is used as a reference, and the reactive voltage optimization control strategy of a substation with a photovoltaic power generation system is constructed considering the characteristics that photovoltaic inverter can continuously regulate reactive power. Taking the internal power grid of an enterprise as an example, the simulation analysis verifies the effectiveness of the control strategy, which can ensure that the voltage and power factor of the grid-connected access point are qualified. At the same time, the voltage fluctuation of the grid-connected point can be reduced, and the network consumption can be reduced.