Energy storage system with PV generation and on-line UPS functions

In this paper, an energy storage system (ESS) with a photovoltaic (PV) generation and an on-line uninterruptible power supply (UPS) functions is proposed. The proposed system is composed of an inverter, a bidirectional converter, a PV converter, and a battery converter. The inverter provides a regulated sinusoidal output voltage to the load like the on-line UPS. The bidirectional converter operates as an inverter or a rectifier to transmit the power to and from the grid. The PV converter extracts the maximum power from the PV panels and sends it to the DC-bus. The battery converter is connected in parallel with the DC-bus.