DocumentCode :
3623503
Title :
Evaluation of Josephson and Von Klitzing constants by frequency
Author :
F. Castelli
Author_Institution :
Dipartimento di Elettrotecnica, Milano Univ., Italy
fYear :
1993
Firstpage :
537
Lastpage :
540
Abstract :
The author investigates a new method to evaluate Josephson (Kj) and von Klitzing (Rk) constants. The evaluation is based on a comparison of electrical (Pe) to mechanical (Pm) power. The Pe and Pm are the powers of a dynamo, in the form of a DC brushless tachometer (DBT), driven by a brushless motor, at a frequency of rotation f. Pe/Pm to the square of, either the output voltage, V, or the current, I of the DBT, provides the ratios /spl alpha/ = V/sup 2f and /spl beta/ = I/sup 2/f. During two tests, a /spl alpha/ and /spl beta/ were respectively maintained and then evaluated by a linear regression of either V/sup 2/, or I/sup 2/, t f and the resistance by /spl radic/(/spl alpha/spl beta/). The expected one standard deviation or (1/spl sigma/) is /spl les/ 0.01 ppm.
Keywords :
"Frequency","Voltage","Force measurement","Switches","Resistors","Magnetohydrodynamic power generation","Brushless motors","Testing","Uncertainty","Velocity measurement"
Publisher :
ieee
Conference_Titel :
Instrumentation and Measurement Technology Conference, 1993. IMTC/93. Conference Record., IEEE
Print_ISBN :
0-7803-1229-5
Type :
conf
DOI :
10.1109/IMTC.1993.382585
Filename :
382585
Link To Document :
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