Influence of mica paper type and construction on the dielectric properties of VPI and resin rich high voltage insulation

Tests have shown that the quality of a high-voltage insulation is influenced by the type and quality of the mica paper used. A homogeneous and fine distribution of the mica scales as given in the calcined mica paper results in a higher dielectric strength compared to uncalcined mica paper. Other contributing factors are the carrier used, the type of application method employed, and the widths of the tapes, all of which can have a major effect on the electrical strength. Taking this into account, producers and users of high-voltage insulating materials may develop and select the optimum quality for a given insulation design requirement