Efficiency Evaluation of a Motor with SMC Core

We have investigated a motor with a stator made of SMC, soft magnetic composite material. The features of SMC are improvements in eddy current loss at the flux density changing, as SMC is made by a compaction of iron powder covered with insulated layer. Especially, downsizing of a motor core and simplification of production process of stator is expected by using the material.The material has a disadvantage in efficiency of motor driving as the iron loss is worse than that of conventional laminated core, but we found that the driving efficiency will be close to the laminated core. We expect also the improvement of further efficiency with the optimization of a 3-dimensional magnetic circuit.