Development of superconducting magnetic bearing for flywheel energy storage system

• Published in: Cryogenics (Guildford) Vol. 80; pp. 234 - 237
• Main Authors: Miyazaki, Yoshiki, Mizuno, Katsutoshi, Yamashita, Tomohisa, Ogata, Masafumi, Hasegawa, Hitoshi, Nagashima, Ken, Mukoyama, Shinichi, Matsuoka, Taro, Nakao, Kengo, Horiuch, Shinichi, Maeda, Tadakazu, Shimizu, Hideki
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.12.2016; Elsevier BV
• Subjects: Carbon fiber reinforced plastics; Coiling; Coils; Cooling; Energy; Energy storage; Flywheels; High temperature; Storage; Storage capacity; Superconductivity
• ISSN: 0011-2275; 1879-2235
• DOI: 10.1016/j.cryogenics.2016.05.011

•The world largest-class FESS with a SMB has been completed and test operation has started.•The SMB was capable of supporting the flywheel, having the weight of 4000kg.•The HTS bulks were cooled by the low pressure helium gas without any contact.•The levitation test has lasted for many hours and the SMB has been operated stably for 500h.•It is possible to apply this system for railways to store the regenerative braking energy which would be cancelled. We have been developing a superconducting magnetic bearing (SMB) that has high temperature superconducting (HTS) coils and bulks for a flywheel energy storage system (FESS) that have an output capability of 300kW and a storage capacity of 100kWh (Nagashima et al., 2008, Hasegawa et al., 2015) [1,2]. The world largest-class FESS with a SMB has been completed and test operation has started. A CFRP flywheel rotor that had a diameter of 2m and weight of 4000kg had a capability to be rotated at a maximum speed of 6000min−1. The SMB using superconducting material both for its rotor and stator is capable of supporting the flywheel that had the heavy weight and the high seed rotation mentioned above. This paper describes the design of the SMB and results of the cooling test of the SMB.