Selection of Contactless-Power-Supply Housing Material Considering Eddy Current Loss, Thermal Load, and Structure Safety

This paper deals with the selection of the housing material of the contactless power supplier (CPS) used for the field winding power supply in wound field synchronous machine (WFSM). The housing of the CPS encloses the rotary transformer and the converter of secondary side. The housing prevents the damage of ferrite core in the rotary transformer and the secondary converter due to centrifugal force in the highest speed, 10,000 rpm. Therefore, the housing should have been designed considering not only strengthen, but also lighten. Furthermore, efficiency is also one of important characteristics in power transfer to improve the whole system efficiency. Taking account of aforementioned points, the stainless steel (SUS) and aluminum (Al), which are commonly used as housing materials, were under reviewed as CPS housing. After comparing the characteristic of CPSs according to housing material in term of eddy current loss, thermal characteristic, and mechanical stability, the appropriate housing material is suggested. After that, experimental results deriving from tests are presented to confirm the analysis results.