Uninterruptible Power Supply System Configurations: Reliability & Cost-Benefit Analysis

The paper presents the system’s reliability study for the different configurations of Uninterruptible Power Supply (UPS) systems. The five main UPS system design configurations namely: Capacity, Isolated Redundant, Parallel Redundant, Distributed Redundant, and System plus System Redundant were considered and comparisons on the resultant system’s reliability parameters together with the system’s reliability sensitivity analysis were discussed in detail. UPS reliability parameters such as failure rates, Mean Time Between Failures, and Availability can be estimated from the proposed system’s reliability estimation methods. Cost/benefit analysis that considers the cost of outage and the cost of UPS system is then being carried out to ensure that the UPS design configuration and application satisfies the power requirements at the right cost.