Cost-effective bidirectional chopper-based battery link UPS with common input-output bus line and its control scheme

This paper presents a nonisolated prototype of an input-output common bus line UPS circuit topology using IGBT modules, which incorporates a bidirectional power converter circuit for battery bank interface, as well as its related-specific current-mode control strategy. The steady-state operating principle of the power conversion circuit system topologies and control strategy are described herein. Feasible experimental results of this cost-effective and high-performance UPS topology with a two-quadrant chopper-fed battery bank are illustrated for a 3 kVA UPS and discussed as compared with a conventional UPS with battery bank connected to an HVDC bus.