[WB5] Assembled Conductors

3:45 PM - 4:15 PM JST(6:45 AM - 7:15 AM UTC)

[WB5-03-INV] Development of UROCOIC Conductors by Helical Fusion Co., Ltd.

*Junichi Miyazawa¹, Yoshiro Narushima², Yuta Onodera², Tomosumi Baba², Shinji Hamaguchi², Nagato Yanagi², Hirotaka Chikaraishi², Hiroki Chikuma¹, Hitoshi Tamura¹, Takuya Goto¹ (1. Helical Fusion Co., Ltd. (Japan), 2. National Institute for Fusion Science (Japan))

Keywords:

REBCO,Stacked tape conductors,Joint resistance,Fusion

Helical Fusion Co., Ltd. (HF) is a Japanese fusion startup established in 2021. HF aims to realize the social implementation of fusion energy through the development of helical fusion reactors. HF has developed a unique high-temperature superconducting (HTS) UROCOIC (Unitized Reinforcing Outer Cover On Internal Components) conductor. The UROCOIC conductor consists of simple stacks of REBCO tape and reinforcing tape, which are bundled together with cooling tubes using a component called an ‘armor.’ The UROCOIC conductor offers excellent flexibility, making it particularly suitable for the manufacture of coils for fusion reactors that require twisting or bending, such as helical or modular stellarator fusion reactors.HF received an SBIR (Small/Startup Business Innovation Research) grant from the MEXT (Ministry of Education, Culture, Sports, Science and Technology) in 2023 and is currently developing UROCOIC conductors under a five-year plan. This plan involves the manufacture and electrical testing of double pancake coils with an outer diameter of approximately 0.6 m, as well as the manufacture and electrical testing of helical coils with a major diameter of approximately 2 m. A double pancake coil using UROCOIC conductors has already been manufactured, and preparations are underway for testing in September 2025. In manufacturing this coil, new technologies such as the ‘Faro shuffle connection method’ and ‘atmospheric pressure plasma pretreatment’ were developed. Preparations are also underway for the UROCOIC helical coil, and manufacturing of a helical coil winding machine has already begun.