Experimental and analytical determination of proximity losses in a high-speed PM machine

This paper presents a methodology for analysing ac winding loss effects which can be significant when considering high-power density, high-efficiency and high-speed machine designs. A combination of finite element analysis (FEA) and experimental measurement has been employed to evaluate the components that contribute to the overall winding power loss. A number of conductor profiles and conductor arrangements have been investigated to give a more general insight into the ac winding phenomena. An experimental approach based on a partially wound stator is employed to allow different winding and conductor arrangements to be evaluated in a timely and accurate manner, as compared with numerical analysis or hardware tests on the complete machine assembly. The outcomes identify the temperature variation of ac winding loss, which can reduce with increasing temperature, and proposes an effective modelling and test method through which the effects can be quantified and experimentally verified.