Patent US3678335A successfully refreshed from Google Patents.
US3678335A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit breaker for high voltage direct current
Assignee: ABB Norden Holding AB
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Filing: 1971-06-01
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Granted: 1972-07-18
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Expires: 1991-06-01
Abstract
Abstract In a switching device for HVDC comprising two series-connected breaker units, the operating release of the device comprises a time delay means controlled by the voltage of the HVDC network. When breaking at voltages above a certain level, one of the breaker units opens a predetermined time before the other one, thus reducing the switching over-voltage. Below said level, however, the breaker units open simultaneously.
Inventors
- 👤 Walter Pucher
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:36
CPC Classifications
H; H01; H01H; H01H33/00; H01H33/02; H01H33/59; H01H33/596; H01H33/04; H01H33/16; H01H33/166; H02; H02H; H02H3/00; H02H3/02; H02H3/021; H02H7/00; H02H7/26; H02H7/268; H01H33/14
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
105 words
Electric switching device for a high voltage direct current line (3), said device comprising at least two series-connected breaker units of the type producing a counter voltage, in which the release circuit of the switching device comprises a voltagecontrolled time delay means (11) which by means of a voltagesensitive member is arranged to be influenced by the potential of the line in such a way that when breaking at voltages above a certain level one of the breaker units opens before the other one and is thus solely responsible for breaking the current, whereas at voltages below said level, both the breaker units open simultaneously.
Claim 2
Dependent Claim
105 words
Electric switching device for a high voltage direct current line (3), said device comprising at least two series-connected breaker units of the type producing a counter voltage, in which the release circuit of the switching device comprises a voltagecontrolled time delay means (11) which by means of a voltagesensitive member is arranged to be influenced by the potential of the line in such a way that when breaking at voltages above a certain level one of the breaker units opens before the other one and is thus solely responsible for breaking the current, whereas at voltages below said level, both the breaker units open simultaneously.
Claim 3
Dependent Claim
19 words
Switching device according to claim 1, in which each of said breaker units consists of a separate circuit breaker.
Claim 4
Dependent Claim
44 words
Switching device according to claim 1, in which the release circuit is arranged to be directly influenced by the voltage-sensitive member in such a way that the switching device is automatically released if the potential on the DC line drops below a certain level.
Claim 5
Dependent Claim
56 words
Switching device according to claim 1, in which one of the breaker units is arranged to close later than the other breaker unit, a switching in resistor being connected in series with a contact device parallel to the later closing breaker unit, said contact device being closed only during a switching-in operation of the DC line.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |