Power quality, load and efficiency in UPS installations

Uninterruptible Power Supplies ensure a reliable supply to critical loads. Double-conversion topology is often the preferred choice following its superior protection, but it offers limited efficiency. Energy efficiency challenges following global warming concerns are pushing energy-intensive applications to improve the operating efficiency of their UPS systems. This paper explores the impact of utility power quality and load characteristics on UPS efficiency, by providing data collected on a number of remotely monitored sites scattered throughout the world. Emerging high-efficiency operating modes are introduced and evaluated in light of the resulting typical operating conditions for UPS installations.