Thermal Process in Compound-Structure Permanent-Magnet Synchronous Machine

The mathematical model of the thermal process in compound-structure permanent-magnet synchronous machine is considered in the work. The compound-structure permanent-magnet synchronous machine (CS-PMSM), comprising a double rotor machine (DRM) and a permanent-magnet (PM) motor. For CS-PMSM, it is very important to know the temperature rise and heat dissipation, especially when CS-PMSM is operating at full load. From a mathematical point of view, an compound-structure permanent-magnet synchronous machine is viewed in the form of a complex nine-layer area. In this area, as a mathematical model of the thermal process, a boundary-value problem with external and internal heat sources in a cylindrical coordinate system is proposed. A feature of the mathematical model is that at the boundaries of the layers, the condition of perfect thermal contact is used in the form of equality of derivatives in the direction of a given vector. The problem is solved by the finite element method. The multilayer continuous region is represented as a grid of a separable triangulation domain. After triangulation, the solution of the differential problem is reduced to solving a system of algebraic equations with a sparse matrix of the system. The paper also considered another approach to the study of thermal processes in CS-PMSM, which uses the method of parallel structures.