What is the role of the capacitor in the UPS power supply?

How does it work? What does this wave of capacitive action mean?

The output capacitor is the filter capacitor of the PWM inverter output, which together with the inverter output transformer (or inductor) forms the filter circuit, rather than the compensation capacitor. Its size is determined by the manufacturer's design according to the filtering requirements, not calculated according to the output reactive power. Because of this filtering capacitor, the higher harmonics are filtered out and it is a fixed capacitor circuit for the fundamental waves. Regardless of whether there is a load at the UPS output or not, and regardless of the size of the load, the inverter will always deliver such a capacitive current. The inverter current can be reduced for inductive loads and increased for capacitive loads.

What is the role of the capacitor in the Ups Power Supply?

The cause of this problem is the numerical problem of the load power factor specified by the UPS at rated power. Dual conversion UPS is generally specified as 0.8 (or 0.7), under this condition the selected power device. But you could have set it to 1 and that would be different. The delta transformer UPS is the same, it is in the case of battery operation is the same as the double transformer high frequency machine UPS without output transformer. The choice of inverter power unit and high frequency machine is the same. Therefore, the load power factor of 1 is determined by the manufacturer at the design stage. Of course, because of this design, a 10kVA UPS can carry a load with a 10kW power factor of 1.