Title:
MEASURING METHOD OF CURRENT, MAGNETIC FIELD OR CONNECTION RESISTANCE OF SUPERCONDUCTING LOOP
Document Type and Number:
Japanese Patent JP3175398
Kind Code:
B2
Abstract:
PURPOSE: To enable execution of measurement in a short time and with high accuracy by a method wherein an AC voltage induced in a rotary coil is inputted to a lock-in amplifier with a signal synchronous with the period of rotation of the rotary coil used as a reference signal.
CONSTITUTION: An induced voltage of a rotary coil 11 in a magnetic field of a superconducting loop 3 is made to branch in two, and one is amplified by a DC amplifier 18 and inputted as a reference signal to a measuring terminal 19A of a lock-in amplifier 19, while the other AC voltage is inputted to a measuring terminal 19B. The lock-in amplifier 19 passes only a signal of a frequency of a prescribed period, measures an output voltage thereof and displays it in a display part 19C. A current value of the superconducting loop 3 can be known from the ratio to a current of the superconducting loop 3. This measurement is executed a plurality of times consecutively, a rate of attenuation of the magnetic field is determined from the results of the measurement and the resistance of a connecting part 4 in the superconducting loop 3 is determined.
Inventors:
Mukaiyama Shinichi
Akio Kimura
Koji Mogami
Akio Kimura
Koji Mogami
Application Number:
JP10726293A
Publication Date:
June 11, 2001
Filing Date:
April 12, 1993
Export Citation:
Assignee:
THE FURUKAW ELECTRIC CO.,LTD.
International Classes:
G01R19/00; G01R27/02; G01R33/02; (IPC1-7): G01R33/02
Attorney, Agent or Firm:
Hiroshi Wakabayashi