An uninterruptible power supply

Abstract

The function of an uninterruptable power supply (UPS) is to maintain a power source available in situations where a mains failure would mean loss of information or serious malfunctions in critically vital systems. It may also provide protection against mains power supply disturbances. The aim of this thesis was to construct a UPS that can be used for a computer or most other loads within the same power range. The pulse width modulation UPS built has closed loop control of the output voltage and has alarms to detect mains failure and low battery conditions and the capability to turn itself off before the batteries could be damaged due to over discharging.