A Simplified Control Technique for High Power Factor Corrected Line-Interactive UPS with Tri-Port Transformer

This paper proposes a line-interactive UPS with simplified high power factor control. By applying a tri-port transformer (TPT), the commercial power supply, battery, and load are isolated. For this reason, high safety is obtained. Furthermore, a simplified power control achieves a high power factor and low noise. The proposed method was optimally designed for a 10kVA prototype and verified through experiments. As a result, it was confirmed that an input power factor of 0.98 or higher and a power efficiency of 87.5% can be achieved simultaneously. In addition, a seamless transition to backup operation was achieved, and a stable power supply was confirmed when an input failure occurred.