This article presents three topologies of active 3 Phase Power Factor Correction Circuits which satisfy the following basic requirements: (a) near unity Power Factor, (b) Input current harmonics of below 5% THD and 3% SHD, and (c) Isolated DC output from the input utility.
Often times users of power systems have an unclear notions regarding the configurations of power systems that provide features of redundancy, paralleling and the new notion of multiple source Fault Tolerant Power Supplies (FTPS).
Utility blackouts and brownouts are facts of life. Industry publications cite an average of 100 anomalies in utility power per month. The protection of sensitive equipment by the usage of AC stand alone UPS provides an easy solution, but as this article will show, this solution is far from being either cost effective or power efficient. An integrated DC UPS (DUPS) offers a substantially cheaper, more reliable and more efficient solution.
Most military vehicles with dedicated electronic system on board need a UPS to permit uninterrupted service. The UPS provides the backup time which permits to refuel a DC or AC generator which is the prime input source, or to shut dow in an orderly way if a malfunction occurs on the input feed. This paper outlines the design options for such a DC UPS, and the issues discussed need to be considered while formulating the requirements for such UPS. 1....