No abstract

No abstract

No abstract

No abstract

electrical insulation for multi-stress and high repetition rate (high frequency operation) compact and/or high Surface flashover across solid insulators in vacuum voltage/power electrical systems [4].has found applications in the area of space power systems. One scenario where surface flashover in vacuum can be a Insulating materials play a significant role in the problem in space power systems is a spacecraft operating design and performance of high voltage power systems.in geosynchronous orbit (GEO) or low earth orbit (LEO) They can be used for both insulation purposes and for interacts with the local space environment resulting in the charge storage, in addition to other purposes like heat differential charging of the spacecraft to electrical conduction (as in liquids) and mechanical support (as in potentials of many hundreds to few thousand volts. When solids). Despite the basic understanding of electrical this charging reaches a critical value, surface flashover on breakdown of materials, electrical surface flashover the solid dielectric insulator may occur, resulting in loss phenomena, physical mechanisms responsible for the of high voltage isolation and damage to the space power initiation of such unwanted electrical activities within an systems on board. Similarly, surface flashover can also insulation system composed of such advanced materials occur across insulators in the utility power system in must be investigated before they can be commercially atmospheric pressures as well. In general, random available. The findings of such studies are essential for emission of a small number of electrons at the cathode the development of nano-electric and other advanced results in positive charging of the dielectric surface at the materials and the techniques to predict the reliability of triple junction, thus initiating surface flashover across the the advanced electrical systems which utilize these dielectric. materials.In this paper, we present experimental results of It is widely accepted that the surface flashover surface flashover characteristics of epoxy resin and epoxy phenomenon is due to field emission of electrons at the resin cast with powdered A1203. The samples used in the cathode 'triple-junction' (electrode/insulator/vacuum experiments were produced by using either epoxy resin of interface) when the applied field exceeds a certain known properties or by mixing known quantities of A1203 threshold value [5]. Random emission of a small number with epoxy. The electrode material placed over the of electrons at the cathode results in positive charging of dielectric samples was copper. The flashover studies the dielectric surface at the triple junction. Consequently, were conducted using DC and AC signals separately, and this creates an electron avalanche across the surface surface flashover voltage characteristics and the towards the anode, which is followed by an electrical breakdown voltage wave forms of samples were breakdown and plasma generation on the surface of the determined.dielectric. There are...