Waveform control pulse magnetization for HTS bulk magnet

9th International Workshop on Processing and Applications of Superconducting (RE)BCO Large Grain Materials

物理学;材料科学

Ida, Tetsuya^1 ; Shigeuchi, Koji^2 ; Okuda, Sayo^3 ; Watasaki, Masahiro^4 ; Izumi, Mitsuru^5

National Institute of Technology, Hiroshima College, Hiroshima

725-0231, Japan^1

Chiba University, Chiba

263-8522, Japan^2

Toyohashi University of Technology, Aichi

441-8580, Japan^3

Sumitomo Chemical Co., Ltd., Ehime

792-8521, Japan^4

Tokyo University of Marine Science and Technology, Tokyo

135-8533, Japan^5

关键词: Electromagnetic power;    Feedback systems;    High magnetic fields;    High magnetic flux density;    High temperature superconducting;    Pulsed magnetic fields;    Rotating machine;    Trapped magnetic flux;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/695/1/012009/pdf
DOI  :  10.1088/1742-6596/695/1/012009

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

For the past 10 years, we have studied high-temperature superconducting (HTS) bulk magnets for use in electromagnetic rotating machines. If the magnetic field effectively magnetizes the HTS bulk, then the size of the motor and generator can be reduced without a reduction in output. We showed that the melt-textured Gd-Ba-Cu-O HTS bulk effectively traps a high magnetic field using waveform control pulse magnetization (WCPM). WCPM makes it possible to generate any pulsed magnetic field waveform by appropriately changing the duty ratio of the pulse width modulation. By chopping so that the pulsed magnetic field has a period of about 1ms, the WCPM technology enables active control of the rise time and suppresses magnetic flux motion that decreases magnetization efficiency. This method is also useful for any HTS bulk magnet, and the high magnetic flux density is trapped in the HTS bulk by a single pulse magnetic field. We developed a magnetizer that has a feedback system from the penetrated magnetic flux density to realize WCPM. In this research, using only a single pulse magnetic field of WCPM method at 77K, an HTS bulk with a 45mm diameter and 19mm thickness trapped a maximum magnetic field of 1.63T, which is more than 90% of the trapped magnetic flux density by FC magnetization. This result suggests that the pulse magnetizing method can replace the conventional field-cooled method and promote the practical use of HTS magnets for electromagnetic power applications.