Novel line-interactive uninterruptible power supply

In the paper, a novel uninterruptible power supply (UPS) is proposed with the performance of input current harmonic suppression, input power factor correction and output voltage regulation. This UPS comprises two power converters, a shunt power converter and a series power converter. The shunt power converter is connected to the utility via a link inductor, for providing a compensating voltage, to suppress the input current harmonic and improve the input power factor. The series power converter is connected serially to the load to provide a clean and regulated output voltage. A voltage-mode control algorithm with fast response and simple control circuit is proposed to control the shunt power converter. The series power converter is controlled by a current-mode control to ensure the quality of output voltage. A single-phase prototype is developed and tested to verify the performance of the proposed UPS. Experimental results show that the proposed UPS has expected performance.