Fluid-filled capacitor with pressure interrupter means and internal compressible air chamber

摘要

A capacitor has a polymer housing and a wound metallized film capacitive element received in the housing, with leads connected to terminals on the cover of the housing through a pressure responsive interrupter assembly. An air chamber is provided in the housing, confining a compressible volume of air, and insulating fluid fills the remaining volume of the housing, substantially immersing the capacitive element. The air chamber is advantageously defined by a piston slidably mounted in the housing. Upon a high pressure condition caused by failure of the capacitive element, the volume of air is compressed to cushion the onset of the high pressure, protecting the case from rupture prior to operation of the pressure responsive interrupter assembly.