Stand-Alone UPS System Reliability Analysis and Design Rules for its Improvement

The Internet of Things (IoT) is quickly becoming the backbone of today’s digital infrastructure, and it is increasingly dependent on Edge Computing to provide critical enterprise services. These environments therefore require higher levels of availability (much like data centres). The UPS plays a key role, as the power infrastructure is critical in supporting all elements of IoT, Edge Computing and critical enterprise services. A solution providing high availability is based on a scalable, rack-based UPS with an intrinsic superior reliability (MTBF). A UPS front access for fast and riskless maintenance to reduce the repair time (MTTR) is also a necessary feature. The combination of high MTBF and low MTTR values results in the required high availability value: improving the UPS reliability is therefore a key point. This paper analyses and calculates the influence of the UPS structure on its reliability, describes the main strategies and design rules to be implemented to reach an elevated MTBF and presents the practical results which can be obtained.