A power capacitor includes a body that defines an interior space; and at least one capacitive device in the interior space. The capacitive device includes a first electrode; and a second electrode separated from the second electrode. The power capacitor also includes a dielectric nanofluid in the interior space and between the first electrode and the second electrode, the dielectric nanofluid including: a base dielectric fluid; and nanoparticles dispersed in the base dielectric fluid.

A capacitor provides a plurality of selectable capacitance values, by selective connection of six capacitor sections of a capacitive element each having a capacitance value. The capacitor sections are provided in a plurality of wound cylindrical capacitive elements. Two vertically stacked wound cylindrical capacitance elements may each provide three capacitor sections. There may be six separately wound cylindrical capacitive elements each providing a capacitor section. The capacitor sections have a common element terminal.

A capacitor provides a plurality of selectable capacitance values, by selective connection of six capacitor sections of a capacitive element each having a capacitance value. The capacitor sections are provided in a plurality of wound cylindrical capacitive elements. Two vertically stacked wound cylindrical capacitance elements may each provide three capacitor sections. There may be six separately wound cylindrical capacitive elements each providing a capacitor section. The capacitor sections have a common element terminal.

A capacitor comprising a first electrode and a second electrode where at least the first electrode comprises a ionically conductive material typically having both an electrical and ionic conductivity, such as an oxide. The capacitor further comprises a dielectric material contacting the first and second electrode and comprising a porous material having a surface area greater than 0.5 m.sup.2 of surface/gm of material, and further comprising a liquid containing ions within the pores of the porous material. In certain embodiments, the capacitor additionally comprises a first current collector in contact with the first electrode and a second current collector is contact with the second electrode, where the first and second current collector comprise an electrically conductive material.

An object is to provide a film that provides a capacitor excellent in safety function operability, and that has a high level of dielectric breakdown strength at high temperatures and good element-winding suitability. The object is achieved by a film containing a syndiotactic polystyrene resin and a polyphenylene ether resin, the content of the syndiotactic polystyrene resin in the film being 50 mass % or higher, the content of the polyphenylene ether resin in the film being 10 mass % or higher, wherein (A) the film contains titanium oxide particles as inorganic particles, and the content of the titanium oxide particles in the film is 0.55 mass % or higher and 3 mass % or lower, and/or (B) at least one surface of the film has a reduced peak height Spk of 0.05 ?m or more and 0.30 ?m or less.

It is an object to provide an electrically insulating oil composition that can maintain dielectric breakdown voltage high in a wide temperature range of ?50? C. to 65? C., and can suppress a decrease in dielectric breakdown voltage even in the case of use at high temperature for a long time, and there is provided an electrically insulating oil composition comprising 1,1-diphenylethane and benzyltoluene, wherein the proportion of a para isomer in the benzyltoluene is 45% by mass or more based on a total amount of the benzyltoluene.

The present invention provides a capacitor oil that can maintain breakdown voltage at a high level in a wide temperature range of 50 C. to 30 C., extremely unlikely precipitates as crystals in particular at 50 C. and thus has excellent properties both at normal temperature and a lower temperature. The capacitor oil of the present invention comprises 1,1-diphenylethane and benzyltoluene, wherein the mass ratio of 1,1-diphenylethane to benzyltoluene is 0.8 to 2.0, the total amount of the ortho-isomer and para-isomer in the benzyltoluene is 90 percent by mass or less, and the composition has a 40 C. kinematic viscosity of 3.00 mm.sup.2/s or lower.

A capacitor provides a plurality of selectable capacitance values, by selective connection of six capacitor sections of a capacitive element each having a capacitance value. The capacitor sections are provided in a plurality of wound cylindrical capacitive elements. Two vertically stacked wound cylindrical capacitance elements may each provide three capacitor sections. There may be six separately wound cylindrical capacitive elements each providing a capacitor section. The capacitor sections have a common element terminal.

Methods and systems are provided for impregnating capacitors and other receptacles with a fluid. In one example, a system may include a reservoir of a purified fluid to be used to impregnate one or more receptacles and a manifold configured to withstand an internal pressure differential to cause the purified fluid to infiltrate the manifold. The system may further include a convection oven in which the one or more receptacles and the manifold are located when the one or more receptacles are impregnated with the purified fluid.