Instantaneous Voltage Drop Compensation for UPS System Connected in Parallel with Batteries and Ultracapacitors

This paper proposed an UPS system which is connected in parallel with batteries and ultracapacitors to compensate an instantaneous voltage drop. The topology of the main circuit uses six active switching devices to decrease size and cost of systems. And the proposed UPS system is implemented for 3 [kVA] class. The experimental results shows that the proposed UPS system consist of batteries and ultracapacitors, can compensate a fast instantaneous voltage drop and it has high power factor and low distortion in output voltage and input current.