Dynamic Performance Analysis of a Photovoltaic Power Plant with Integrated Storage for Microgrids Dynamic Support

Abstract

This paper presents a solution to improve the dynamic performance of the frequency-control process in autonomous microgrids by means of photovoltaic (PV) power plants. An energy storage system was integrated in the PV power plant primarily to enhance the power-control capability of the PV system. Because the the focus of this paper is on how the PV-storage system can provide dynamic frequency support in the microgrid, a frequency controller was added to the control scheme of the voltage source converter (VSC) that interfaced the PV power plant with the microgrid. The PV response to frequency deviations was adapted from the existing Romanian grid code and, according to the system’s characteristics, a modified power-frequency curve was proposed. The system being studied was examined through both simulations and experiments, and the results showed that, when the storage system was enabled, the PV power plant improved the microgrid’s dynamic frequency response.