Eddy Current Loss Calculation of High-Speed Permanent Magnet Machine With New Type of Powder Block Hierarchy Structure Rotor

The high-speed permanent magnet machine (HSPMM) is faced with two key problems: the high rotor temperature rise caused by the rotor eddy current loss and the rotor linear speed limitation caused by the rotor stress concentration and the low tensile strength of magnetic materials. To solve the above problems, a HSPMM based on powder block hierarchical structure (PBHS) rotor is proposed in this article. To calculate the eddy current loss of PBHS rotor, an analytical calculation model of eddy current loss based on the penetration depth of multilayer composite structure is proposed, and the loss distribution of each part of HSPMM with PBHS rotor is calculated. Finally, the eddy current losses of the two rotors are compared through loss separation experiments. The comparison results indicate that PBHS rotor can effectively reduce rotor eddy current losses. The experimental results have verified the correctness of the loss analysis, providing a theoretical basis for the design and optimization of PBHS rotor HSPMM.