Discussion on Output Characteristics of High-frequency UPS Driving High-power Inductive Load

When the power supply system of a hydraulic system was reformed, oscilloscopes and power quality testers were used to measure the output characteristics of UPS driving different numbers of motors. Tests showed that the output characteristics of UPS are the same as those of commercial power when driving a single motor, but the current waveform would periodically oscillate after driving two motors. Changing the impedance matching of the system neither suppresses this phenomenon nor changes the change period of current. Finally, two comparative tests were designed to drive different motors with UPS of the same model and different motors with UPS of other brands. The experimental results showed that the periodic change of current waveform is related to the inherent output characteristics of high-frequency UPS.