Patent US4811154A successfully refreshed from Google Patents.
US4811154A
Expired / Lapsed
US
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Apparatus for rapid recognition of short-circuits
Assignee: Siemens AG
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Filing: 1987-07-30
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Granted: 1989-03-07
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Expires: 2007-07-30
Abstract
Abstract The invention relates to a configuration for rapid detection of short-circuits and for generating an electrical trigger command with an electronic measuring and processing configuration for current values, which compared in a digital comparison circuit with predetermined limit values transmits the trigger command. The measuring configuration determines the current over time as well as the voltage of the grid and the resulting complex impedances and power. In addition to segmentation, standardization and scaling of the current and voltage values, a cross correlation function as well as the respective product and quotient of the Fourier transforms of the voltage and the current for frequency ranges associated with each other are determined, so that a respective power and impedance spectrum are obtained for evaluating the state of the installation.
Inventors
- 👤 Gerhard Trenkler
- 👤 Reinhard Maier
- 👤 Thomas Nippert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:58
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/08; G01R31/088; H; H02; H02H; H02H3/00; H02H3/40; H02H3/42
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
169 words
Apparatus for rapid detection of short-circuits in an electrical installation comprising means generating an electrical trigger command operating a circuit breaker of the electrical installation in the event of a short circuit comprising an electronic measuring and processing arrangement receiving instantaneous current and voltage values from the electrical installation, said measuring and processing arrangement comprising a digital comparison circuit comparing the current values to pre-settable limit values and transmitting the trigger command in the event the instantaneous current values exceed at least one of the limit values, the measuring and processing arrangement further comprising means for determining from measured variations of the current and the voltage of a power source of the electrical installation the complex impedances and power, said means for determining from the measured variations being coupled to said digital comparison circuit, whereby the detected complex impedances and power and compared to preset limit values of complex power and impedance and said trigger command is generated when at least one of said preset limit values is exceeded.
Claim 2
Dependent Claim
169 words
Apparatus for rapid detection of short-circuits in an electrical installation comprising means generating an electrical trigger command operating a circuit breaker of the electrical installation in the event of a short circuit comprising an electronic measuring and processing arrangement receiving instantaneous current and voltage values from the electrical installation, said measuring and processing arrangement comprising a digital comparison circuit comparing the current values to pre-settable limit values and transmitting the trigger command in the event the instantaneous current values exceed at least one of the limit values, the measuring and processing arrangement further comprising means for determining from measured variations of the current and the voltage of a power source of the electrical installation the complex impedances and power, said means for determining from the measured variations being coupled to said digital comparison circuit, whereby the detected complex impedances and power and compared to preset limit values of complex power and impedance and said trigger command is generated when at least one of said preset limit values is exceeded.
Claim 3
Dependent Claim
24 words
The apparatus recited in claim 1, further comprising means for converting current and voltage as a function of time into an associated frequency range.
Claim 4
Dependent Claim
21 words
The apparatus recited in claim 1 further comprising means for executing identification calculations and classifications of electrical parameters of the installation.
Claim 5
Dependent Claim
38 words
The apparaus recited in claim 3, further comprising means for tracking, as a function of the power source, superposed high-frequency interference voltages and interference currents of the electrical installation operationally with the electrical parameters and limit values automatically.
Claim 6
Dependent Claim
30 words
The apparatus recited in claim 3, further comprising means for tracking, as a function of the variations of the state of the power source, the electrical parameters and limit values.
Claim 7
Dependent Claim
21 words
The apparatus recited in claim 1, further comprising means for filtering the current and voltage values prior to further signal processing.
Claim 8
Dependent Claim
33 words
The apparatus recited in claim 6, further comprising means for converting the current and voltage values after filtering into digital number sequences and for executing further signal processing with digital electrical function modules.
Claim 9
Dependent Claim
21 words
The apparatus recited in claim 7, further comprising means for dividing the digital number sequences into a time sequence of segments.
Claim 10
Dependent Claim
35 words
The apparatus recited in claim 8, wherein the means for dividing comprises means for dividing the digital number sequences into a time sequence of segments having in each instance an equal number of measured values.
Claim 11
Dependent Claim
24 words
The apparatus recited in claim 8, wherein the means for dividing further comprises means for normalizing each particular segment to a diminishing arithmetic mean.
Claim 12
Dependent Claim
23 words
The apparatus recited in claim 8, wherein the means for dividing further comprises means for scaling proportional to the current and voltage values.
Claim 13
Dependent Claim
20 words
The apparatus recited in claim 8, further comprising means for examining the individual segments in overlapping time and in parallel.
Claim 14
Dependent Claim
20 words
The apparatus recited in claim 8, further comprising means for evaluating parameters characterizing the time sequence of the individual segments.
Claim 15
Dependent Claim
20 words
The apparatus recited in claim 1, further comprising means for performing a cross correlation of the voltage and current values.
Claim 16
Dependent Claim
32 words
The apparatus recited in claim 14, further comprising means for utilizing the maximum of the cross correlation and its position as a function of time for classifying the state of the installation.
Claim 17
Dependent Claim
19 words
The apparatus recited in claim 1, further comprising means for forming Fourier transforms of the voltage and current values.
Claim 18
Dependent Claim
31 words
The apparatus recited in claim 16, further comprising means for forming the conjugate-complex product of the Fourier transforms of the voltage and current values for frequency ranges associated with each other.
Claim 19
Dependent Claim
33 words
The apparatus recited in claim 17, further comprising means for utilizing the magnitude and the phase of individual frequency ranges of the conjugate-complex products for the classification of the state of the installation.
Claim 20
Dependent Claim
47 words
The apparatus recited in claim 12, further comprising means for forming the complex quotient of the Fourier transforms of the voltage and current values for the frequency ranges associated with each other as well as the magnitude and the phase of individual frequency ranges of the quotients.
Claim 21
Dependent Claim
22 words
The apparatus recited in claim 1, further comprising a plurality of digital function modules for parallel investigations of the current and voltages.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-03-06 | 1992-09-05 | 1993-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-06 | 1996-09-05 | 1997-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-06 | 2000-09-05 | 2001-03-07 | $7700.00 | Window Closed / Lapsed |