Influence of thermal stability of sintered NdFeB on electric machine design and its appropriate selection

The appearance of rare earth permanent magnet,especially sintered NdFeB materials,promoted the development of permanent magnet machines.However,the irreversible demagnetization problems of NdFeB materials have been perplexing the extensive applications of NdFeB permanent magnet machines.In order to solve the problem,the influence of thermal stability of sintered NdFeB materials on design of permanent magnet machines and volume of permanent magnet materials was analyzed.Based on the measurement and analysis of many NdFeB permanent magnet materials,the selecting standard,which could calculate the thermal stability through magnetic parameters,was put forward.It is verified that the proposed method ensures the reasonable design and operating reliability of permanent magnet machines.