Electricity: measuring and testing – Impedance – admittance or other quantities representative of... – Lumped type parameters
Patent
1994-03-25
1995-10-24
Karlsen, Ernest F.
Electricity: measuring and testing
Impedance, admittance or other quantities representative of...
Lumped type parameters
364576, G01R 3134, G01R 2316
Patent
active
054613299
ABSTRACT:
A method and circuitry for sampling periodic amplitude modulations in a nonstationary periodic carrier wave to determine frequencies in the amplitude modulations. The method and circuit are described in terms of an improved motor current signature analysis. The method insures that the sampled data set contains an exact whole number of carrier wave cycles by defining the rate at which samples of motor current data are collected. The circuitry insures that a sampled data set containing stationary carrier waves is recreated from the analog motor current signal containing nonstationary carrier waves by conditioning the actual sampling rate to adjust with the frequency variations in the carrier wave. After the sampled data is transformed to the frequency domain via the Discrete Fourier Transform, the frequency distribution in the discrete spectra of those components due to the carrier wave and its harmonics will be minimized so that signals of interest are more easily analyzed.
REFERENCES:
patent: 2591738 (1952-04-01), Spencer
patent: 2624770 (1953-01-01), Yetter
patent: 4156846 (1979-05-01), Harrold et al.
patent: 4303882 (1981-12-01), Wolfinger
patent: 4305132 (1981-12-01), Tsuboshima et al.
patent: 4527101 (1985-07-01), Zavis et al.
patent: 4678990 (1987-07-01), Bicknell et al.
patent: 4744041 (1988-05-01), Strunk et al.
patent: 4751657 (1988-06-01), Imam et al.
patent: 4761703 (1988-08-01), Kliman et al.
patent: 4808932 (1989-02-01), Schulz, Jr. et al.
patent: 4965513 (1990-10-01), Haynes et al.
patent: 4978909 (1990-12-01), Hendrix et al.
patent: 5049815 (1991-09-01), Kliman
patent: 5252915 (1993-10-01), Sedding et al.
"Condition Monitoring of Machinery Using Motor Current Signature Anly" Kryter, et al., Sound and Vibration, Sep. 1989, pp. 14-21.
"An On-Line Computer Based Current Monitoring System for Rotor . . . " Thomson, et al. Turbomachinery International Nov. 1987, pp. 17-24.
Id. Case Study of a Method for Diagnosing AC Industion Motors Using Spectrum Analysis, Jim Reis Entek Scientific Corp., pp. 40-44.
Proceedings of 1st Inter. mach. Mon. and Diag. Conf. Broken Bar Detector For . . . Motors Kliman, Koegl et al. 674-682 (1989).
Bunch Stanley L.
Linehan Daniel J.
Lyster Carl T.
Cutler Jeffrey N.
Karlsen Ernest F.
Martin Marietta Energy Systems Inc.
Skinner Martin J.
Spicer James M.
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