Influence of the welding process on the magnetic properties of a slot-less permanent magnet synchronous machine stator core

In this paper, the influence of the welding process during the manufacturing of small, slot-less permanent magnet synchronous machines (PMSMs) is studied. The focus lies on the change of the magnetic properties and the iron losses in thin, high quality Si-alloyed electrical steel sheets (NO 20). It is shown that the welding process changes the magnetic material properties significantly and increases the specific iron losses. Experimental results are provided for magnetic flux densities up to 1.3T and frequencies in the range of 0.1Hz to 200 Hz.