Advanced thermal management of stator-mounted PM machines

This thesis investigates the electromagnetic performance and thermal behaviour of stator-mounted permanent magnet (PM) machines, with a focus on various cooling methods.The electromagnetic performances of five stator-mounted PM machines are evaluated using Pareto fronts obtained through a multi-objective genetic algorithm, exploring the relationships among maximum torque, copper loss, and PM volume. The thermal performance of three representative stator-mounted PM machines, along with a surface-mounted PM machine, is analysed under both natural cooling and water-jacket cooling at different rotor speeds. For active cooling methods, forced air cooling and forced liquid cooling are applied to a modular FSPM machine. In the forced air cooling study, the effects of inlet conditions, flux gap width, and rotor speed are examined. For forced liquid cooling, three modified liquid cooling techniques are proposed. Furthermore, two coolants are tested in semi-flood cooling, and a series of simulations under different flux gap widths are conducted to assess their effectiveness.