Practical design considerations of stator lamination fixtures in permanent magnet machines

It is mechanically convenient to employ end plates and pulling bars to support the stator lamination in PM machines. However, the structure may degrade the electromagnetic performance of the machine if poorly designed. This paper shows that the pulling bar and the end plate structure could affect machines' performance through two mechanisms. Particularly, the conductive cage mechanism is more dangerous and is generally overlooked. The paper thus proposes three design rules to eliminate the adverse effect associated with the supporting structure of the stator lamination. Experimental and simulation validations confirm the effectiveness of proposed design rules.