Magnetic losses in Bi2223 high temperature superconductors measured by AC and DC magnetization method

The properties of Bi2223 high temperature superconductor (HTS) tapes are improved in long length and high current-carrying capacity for its applications. But AC loss is still very high, which increases its economic feasibility in power engineering applications. Extensive investigations have shown that the mechanism of generation of AC loss in HTS is different from that in LTS because of its unique characteristics. In this study, AC losses in Bi2223 (HTS) tapes were measured by vibrating sample magnetometer at 77 K and AC susceptibility meter. The effects of different factors, such as, frequency and amplitude of AC applied magnetic field and/or amplitude of DC applied magnetic field, were investigated on the AC susceptibility in Bi2223 HTS tapes. Instead of Bean critical state model, flux dynamics were investigated to describe the experimental results.