June 28, 2015 to July 2, 2015
JW Marriott Starr Pass Resort
Etc/GMT-7 timezone

R&D status of highly efficient Stirling-type cryocooler for superconducting drive motor

Jun 29, 2015, 11:45 AM
Tucson Ballroom E

Tucson Ballroom E

Contributed Oral Presentation CEC-03 - Cryocoolers (Non-Aerospace) C1OrA - Cryocoolers for Superconducting Applications


Mr Jun Watanabe (Kyoto University)


In this paper, we try to develop highly efficient Stirling-type cryocooler for the next generation drive motor. Target motor is a High Temperature Superconducting Induction/Synchronous Motor (HTS-ISM). Although basic structure of HTS-ISM is almost the same as that of the conventional squirrel-cage induction motor, it can rotate at synchronous speed by use of the superconducting rotor windings. It has been clarified that the torque density can be enormously enhanced at the synchronous rotation. By enhancing torque density, it is possible to realize the direct-drived operation without transmission gears. The transmission system brings some loss because the gears always rotate during the driving. In order to improve the overall energy conversion efficiency of power-train system, the direct-drive motor is expected to be realized. On the other hand, HTS-ISM has been operated in liquid nitrogen. This method, however, has several disadvantages such as the mechanical loss due to the viscosity of liquid nitrogen, the safety reason, etc. Therefore, we have studied the conducting cooling system. It is necessary to develop small sized high power cryocooler in order to realize the high efficiency of overall HTS-ISM power-train system. Generally speaking, Stirling-type cryocooler has advantages in terms of size and efficiency. We firstly designed, fabricated, and tested the actuator at various frequency and in several wave patterns, and we realized the high efficiency of the actuator. Next, we set up pulse-tube cryocooler to this compressor, and measured the cooling capacity of this Stirling-type cryocooler. Experimental and analysis results are to be reported and discussed. *This work has been supported by Japan Science and Technology Agency under the program of Advanced Low Carbon Technology Research and Development Program (JST-ALCA).*

Primary author

Mr Jun Watanabe (Kyoto University)


Prof. Naoyuki Amemiya (Kyoto University) Mr Shuhei Iriyama (Kyoto University) Dr Taketsune Nakamura (Kyoto University) Mr Takuro Ogasa (Kyoto University) Mr Yoshimasa Ohashi (AISIN SEIKI , Co., Ltd)

Presentation materials