Varying magnet type and stack length in a surface PM soft magnetic composite machine

摘要

This paper examines the effect of varying the magnet type and stack length of a surface PM machine using soft magnetic composite pole-pieces. Firstly, the finite-element modelling and testing of a 9 slot, 8 pole, 400 W machine with a bonded rare-earth magnet ring is described. Secondly, the use of alternative magnet types and the effect of stack length changes on the machine loss and material cost are investigated using a combination of analytical and finite-element results.