Autonomous Operation of Single Stage Solar PV-BES Based Microgrid

Abstract

This paper deals with the autonomous operation of solar photovoltaic (PV) and battery energy storage (BES) based microgrid. The single stage PV system is incorporated to the DC link of voltage source converter (VSC). The BES is incorporated across the DC link through a bidirectional converter for load management. VSC operates on a voltage control algorithm in standalone mode. A perturb and observe approach is implemented to achieve the peak power from a solar PV array. The charging and discharging currents of battery, are controlled by the bidirectional converter. The solar PV-BES microgrid in standalone mode, controls the power requirement by the loads and maintains the frequency and voltage within stipulated limits. The implementation of bidirectional converter has reduced the battery rating as compared to the battery incorporation across the DC link of VSC directly. The operation of proposed microgrid is observed satisfactory in steady state and dynamic conditions and validated through test results on a developed prototype.