Electrical machine with dual insulated coil assembly

摘要

An electrical coil assembly for use in a flooded electrical machine operating in an electrically conductive and/or chemically aggressive medium incorporates an electrical cable coil winding 208 and a laminated magnetic core 202. The electrical coil winding is wound of electrical cable 210 with dielectric insulation 214 that is also a waterproof molecular barrier and is covered with at least one layer of waterproof adhesive material 216. The magnetic core is substantially surrounded with a dielectric insulation layer 204, which is covered with at least one layer of waterproof adhesive material 206. The combination of dielectric insulation and waterproof adhesive layers provide protection against the ingress of water and accordingly reduce risk of electrical fault and failure of the electrical coil assembly in submerged service. Encapsulation material 422 and an anti-fouling or fouling release layer 417 may be provided. A dielectric plate 418 e.g. fibreglass, may also cover the windings. A method for manufacturing an electrical coil assembly is disclosed and winding layouts are disclosed to minimise dielectric stress. Materials for the layers are disclosed and the coil may also be used in a transformer or inductor.