Analytical Analysis and Cooling System Design of a High-Speed Permanent Magnet Motor Utilizing an Amorphous Metal Core

Due to the over-heating problems of the totally-enclosed high-speed permanent magnet synchronous machine (PMSM) with an amorphous alloy (AA) core, a hybrid cooling system is exhibited in this paper to balance the temperature rise based on a prototype rating 30000 rpm at 15kW. The analytical models of the cooling ability and the frictional loss generated in the rotor ducts are established with direct relations to the cooling-structure parameters. The sensitivity of each parameter to the temperature rise of the machine is analyzed, and the parameter scopes are then determined. The computational fluid dynamics (CFD) methods are employed to calculate the fluid flow and the temperature distribution of the machine. The influences of the numbers and sizes of the cooling ducts to the efficient cooling-air quantities and temperatures are analyzed. The feasible parameters were thus determined with the proper temperature rise distributed.