| 摘要 |
PURPOSE:To keep corona starting voltage to a numerical value which is higher than that of a rated voltage by 200% or more, by causing insulating gas having its atmospheric pressure at about 1atm. P to remain at a cavity part in an inside of a capacitor element and sealing the peripheral part of the element by making a setting-reaction of a synthetic resin take place, while applying pressure to the synthetic resin at a pressure that is greater than atmospheric pressure when the above peripheral part is molded with the synthetic resin. CONSTITUTION:A capacitor 7 is put in a mold 6 to be molded which is set in a vacuum container 1 and water vapor and the like in the container are removed by heating with a heater 5 while operating a vacuum pump 2 and the inside atm. P of the container is raised at 1atm. P or more, for example, up to 1.5atm. P by making insulating gas, for example, an SF6 gas flow in the container and it is kept as it is. Then, pressure of the SF6 gas is decreased up to atmospheric pressure. After that, a synthetic resin, for example, an epoxy resin is injected in the mold 6 to coat the peripheral part of the capacitor element and then its element is surrounded with the epoxy resin. Then the epoxy resin is thermally set in a state that the inside atmospheric pressure of the capacitor element is raised to more than 1atm. P, for example, up to 1.5atm. P by making air flow in the element by an air compressor 8. In this way the inside of the capacitor element comes to a state where the SF6 gas is sealed in gaps arranged inside the above element. |
