There is provided a pressboard for high-voltage devices, the pressboard having a density of 0.6-1.3 g/cm.sup.3 according to IEC60641-2, and including 1-15% microfibrillated cellulose, MFC, based on the total dry weight of the pressboard. There is also provided an insulation element including such pressboard, wherein the pressboard is impregnated with an electrically insulating compound. There is also provided use of such insulation element in a high-voltage device as well as a high-voltage device comprising such insulation element, wherein the high-voltage device may be a power transformer.

There is provided a pressboard for high-voltage devices, the pressboard having a density of 0.6-1.3 g/cm.sup.3 according to IEC60641-2, and including 1-15% microfibrillated cellulose, MFC, based on the total dry weight of the pressboard. There is also provided an insulation element including such pressboard, wherein the pressboard is impregnated with an electrically insulating compound. There is also provided use of such insulation element in a high-voltage device as well as a high-voltage device comprising such insulation element, wherein the high-voltage device may be a power transformer.

An aramid-mica composite insulating nanopaper and a preparation method thereof are disclosed. A mixture of mica and urea is subjected to a solid-phase ball milling, to obtain nano mica modified with amino groups on the surface, which is then assembled with the aramid nanofiber by stepwise suction filtration according to the present disclosure, to form an ordered nanopaper, thereby obtaining an aramid-mica composite insulating nanopaper with ultra-high insulation performances.

An aramid-mica composite insulating nanopaper and a preparation method thereof are disclosed. A mixture of mica and urea is subjected to a solid-phase ball milling, to obtain nano mica modified with amino groups on the surface, which is then assembled with the aramid nanofiber by stepwise suction filtration according to the present disclosure, to form an ordered nanopaper, thereby obtaining an aramid-mica composite insulating nanopaper with ultra-high insulation performances.

An aramid-based paper comprising at least 90 wt. % of aramid material, the aramid material including at least one of aramid shortcut and aramid fibrid, the paper including at most 40 wt. % aramid pulp, calculated on the total amount of aramid material, wherein the paper includes 0.1-10 wt. % of polyamido-amine epichlorohydrin (PAE). It has been found that the incorporation of 0.1-10 wt. % of polyamido-amine epichlorohydrin (PAE) into an aramid-based paper including at least 90 wt. % of aramid material calculated on the weight of the paper not including the PAE, the aramid material including at least one of aramid shortcut and aramid fibrid, the paper including at most 40 wt. % aramid pulp, leads to a surprising improvement of the z-strength and the tear strength of the paper.

The present invention is to provide a power cable with a termination connection box, in which the occurrence of heterojunction interfaces between the power cable and the termination connection box are reduced to prevent accumulation of space charges and an electric field may be mitigated.

The present invention is to provide a power cable with a termination connection box, in which the occurrence of heterojunction interfaces between the power cable and the termination connection box are reduced to prevent accumulation of space charges and an electric field may be mitigated.

A cellulose based pressboard for insulation in an electrical power transformer, the pressboard includes polyvinylamine (PVAm), and polyacrylamide (PAM), in a combined amount of between 0.01% and 20% by weight of the pressboard.

A cellulose based pressboard for insulation in an electrical power transformer, the pressboard includes polyvinylamine (PVAm), and polyacrylamide (PAM), in a combined amount of between 0.01% and 20% by weight of the pressboard.

A multiple parallel conductor that is easy to produce and use and has a plurality of twisted, insulated individual conductors. The individual conductors are arranged above one another in a plurality of sub-conductor bundles arranged next to one another. A strip is applied to the multiple parallel conductor on a side surface of the multiple parallel conductor in the longitudinal direction of the multiple parallel conductor, on which strip spacer plates are arranged so as to be distributed in the longitudinal direction, and the multiple parallel conductor together with the strip and the spacer plates is wrapped with a wrapping.