Novel Method for the Determination of Eddy Current Losses in the Permanent Magnets of a High-Speed Synchronous Machine

This paper reviews several methods to identify the eddy current losses in the permanent magnets of a high-speed high power density synchronous machine for an aircraft application. The rotor losses of such a machine are of particular importance, as the cooling of the rotor is poor. They originate from higher time harmonics in the voltage supply of the machine from inverters and from the spatial harmonics due to the slot openings of the stator. Because a preliminary loss calculation should be possible without time-consuming finite-element simulations, especially during the design phase, a novel combined analytical-numerical method is shown and paired with another analytical method in order to consider the different loss sources and to save calculation time. The result is compared to a finite element simulation.