Numerical simulations on the AC loss of REBCO stacks under rotating magnetic fields  

作　　者：Yuan Wang Jin Fang Timothy Haugan Rodney A.Badcock James G.Storey Zhenan Jiang 

机构地区：[1]School of Electrical Engineering,Beijing Jiaotong University,Beijing 100044,China [2]The Air Force Research Laboratory,Aerospace Systems Directorate,1950 Fifth St.Bldg 18,Wright-Patterson AFB,OH 45433,United States of America [3]Paihau-Robinson Research Institute,Victoria University of Wellington,Wellington,Lower Hutt 5011,New Zealand

出　　处：《Superconductivity》2024年第3期34-44,共11页超导（英文）

基　　金：New Zealand Ministry of Business,Innovation and Employment under the Advanced Energy Technology Platform program“High power electric motors for large scale transport”contract number RTVU2004;in part supported by the Air Force Office of Scientific Research under award number FA2386-22-1-4054;Yuan Wang acknowledges financial supports from the Chinese Scholarship Council(CSC)and the CSC/Victoria University of Wellington Scholarship.

摘　　要：AC loss presents a significant challenge for high-temperature superconducting (HTS) rotating machines. To date, the behaviour of total AC loss (Qtol) (with current) and magnetization loss (Qm) (without current) in a single HTS tape under rotating magnetic fields (RF) have been explored. However, a research gap remains in understanding how these findings translate to the more complex HTS windings of rotating machines. Further exploration is needed to understand the loss behaviour of more complex HTS structures, such as HTS stacks. In this work, Qtol and Qm, in the HTS stacks under RF and a perpendicular AC standing wave magnetic field are numerically investigated. Two different RF models are considered: one is the Uni-RF model, characterized by a uniform field with equal field amplitudes and phases at each position, and the other is a non-uniform field created by a rotating Halbach array, referred to as the Hal-RF model. The dependence of AC loss on parameters such as the number of tapes in the stacks, tape width (2a), and the inclination angle (α) of tapes, which refers to the angle between the normal direction of the stack and the vertical direction, have been explored. The number of tapes in the stacks ranges from 1 to 16, α ranges from 0° to 90°, and the tape width includes 4 mm and 40 mm. Additionally, different rotating field directions are also considered. Interestingly, the analytical values from Brandt and Indenbom equation for Q_(m) of a superconducting strip (BI-strip) are close to Q_(m) results of the stacks under the standing wave at high fields, while they are over twice as high as those in the Hal-RF model at 1 T. This suggests the BI-strip equation is not reliable for predicting Q_(m) under RF at high fields. We also show in the Hal-RF model that different rotation directions of the field lead to varying Q_(m) and Qtol when asymmetric Jc (B, θ) data are applied. Moreover, it has been observed that the inclination angle has no impact on Q_(m) under uniform RF while significantly impacts both Q_

关 键 词：STACKS Rotating magnetic field Magnetization loss Total AC loss finite element method(FEM) 

分 类 号：TM26[一般工业技术—材料科学与工程]