Design considerations of transverse flux linear machines for eelectromagnetic launch applications

This paper deals with the design of transverse flux linear machines (TFLM) targeting electromagnetic launch (EML) applications, and the issues pertinent to its topology selection, design optimization and thermal modeling are discussed. By overall comparison of practical topologies and technologies of the TFLM, a tubular moving-magnet topology with separated flux paths is believed to be more appropriate. Design optimization is then performed to maximize the thrust force under specific volumetric constraints. It is shown that the thrust force is more sensitive to the stator segment length, instead of the magnet thickness. Regarding the overload requirement inherently in EML systems, special focus is given on the thermal characteristics of the TFLM at overload conditions, and it is proven that the machine shows appreciable overload capability. Measurements carried out on a prototype TFLM have validated the predictions.