Design and Development of a Smart Solar Photovoltaic Uninterruptible Power Supply System

This project focuses on the research, development, and implementation of a solar Photo Voltaic (PV) Uninterruptible Power Supply (UPS) as a backup source of energy from the commonly used hydrocarbon or coal-fired in Botswana. These are the UPS system that will serve as a power backup for a connected load. The design consists of; a solar PV panel, solar charge controller, inverter circuit, and a 2-channel relay ‘for switching between the solar and main supplies.’ For the UPS system, a solar PV panel converts solar energy to electrical energy. The solar PV panel feeds a Direct Current (DC) output that charges a 12V battery which then connects an inverted circuit where the DC is converted to Alternating Current (AC). A step-up transformer is then used to increase the voltage from 12V to 230V. A relay is programmed to automatically switch between the solar supply and the AC main supply in case of failure of one of the sources and use the stored charge from the battery to supply the load when both sources fail.