Электромагнитный и тепловой анализ электрических машин из композитных материалов

Abstract

The progress in improvement of the electrical, thermal, and mechanical properties of composite materials opens new possibilities for replacing metal components in constructing electrical machines. Owing to low density of the majority of these materials in comparison with conventional materials, it becomes possible to decrease the specific weight and achieve better processability due to minimal machining and the possibility of making parts having the finished shape. Studies of using composite materials in individual units of electrical machines show the possibility of minimizing material intensity, increasing energy density, and achieving better energy efficiency. One of possible ways to increase energy density and energy efficiency is to construct high-speed electrical machines that are able to generate maximum power with the minimum amount of active and structural materials. The characteristics of electrical machines are determined by losses, which in turn depend on the electromagnetic and thermal properties of the applied materials. In this respect, composite materials differ favorably from conventional materials. Thus, composite materials consist of plastic bases reinforced with fillers. By combining dissimilar materials, a new material is obtained, the properties of which may differ significantly from the properties of its individual components. The results from a comparative analysis carried out for three designs of electrical machines with different contents of composite materials are presented. Full electromagnetic and thermal analyses of these designs carried out using the finite element methods are given, their specific characteristics are determined, and their efficiencies are estimated. It has been found that the weight of an electrical machine that consists completely of composite materials is by 73% smaller than that of an electrical machine made of conventional materials. The efficiency of an electrical machine made fully of composite materials is 92%, a conclusion that confirms good prospects of applying composite materials in electrical machine components. The thermal analysis results confirm that an electrical machine made completely of composite materials will have full operability.