The capacitor used as the AC -Filter in the power electronic equipment; for example high-power UPS. In the circuit will use the DC-LINK capacitor C43/C42. The snubber capacitor of C51/52/54. in Generally, the output filter capacitor C45 is necessary. Sometimes we also use an X2 capacitor in the position of power input (1uF/275VAC etc.) Using metalized film capacitor replace electrolytic, it can better resistance the high dv/dt and high ripple current. It have a good self healing that can prolong the lifetime