Energy management and control of solar aided UPS

Abstract

Solar photovoltaic (PV) powered UPS system requires a smart control and energy management techniques along with battery charger for efficient power transfer and energy storage. This paper presents the energy management system and controller design of the solar aided UPS implemented with the half-bridge converter. Designed DC-DC converter employs the voltage mode control using Maximum Power Point Tracking (MPPT) and the battery charging control loop. The control objective is to balance the power · ow from the PV module to the battery and the load such that the PV power is utilized effectively and the battery is charged with three charging stages. Unlike conventional UPS systems, the control technique prioritizes solar power over grid to charge the battery. To improve the battery efficiency and life time different SOC levels have been chosen and energy management is done by monitoring the SOC.