US3657607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impedance-increasing method and apparatus as part of a hvdc circuit breaker
Assignee: Raytheon Co
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Filing: 1971-03-09
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Granted: 1972-04-18
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Expires: 1991-03-09
Abstract
Abstract The high voltage DC circuit breaker must generate a variable impedance which increases gradually from negligibly small, when the breaker is closed, to infinitely large, after it has been opened. This invention describes a novel impedance-increasing method comprising serially connected resistance and switch means and a capacitor which shunts both. The switch means, which must be capable of opening and closing a high voltage, is programmed to rapidly switch on and off with increasing offtime so that the time averaged impedance of the DC circuit is increased to an offswitched condition.
Inventors
- 👤 Wolfgang Knauer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 08:35
CPC Classifications
H; H01; H01H; H01H33/00; H01H33/02; H01H33/59; H01H33/596
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
118 words
A high voltage DC circuit breaker, said circuit breaker comprising a line switch and an impedance-increasing means connected in parallel to said line switch so that, when said line switch is opened, current is transferred to said impedanceincreasing means, the improvement comprising: said impedance-increasing means comprising a cyclically operable switch and an energy-absorbing resistor in series with said cyclically operable switch and means to operate said cyclically operable switch, a rate of voltage rise limiting capacitor connected in parallel to said series combination of said cyclically operable switch and said energy-absorbing resistor, so that the time averaged impedance of said impedanceincreasing means increases as said cyclically operable switch is operated to have an increasing ratio of offswitch time.
Claim 2
Dependent Claim
118 words
A high voltage DC circuit breaker, said circuit breaker comprising a line switch and an impedance-increasing means connected in parallel to said line switch so that, when said line switch is opened, current is transferred to said impedanceincreasing means, the improvement comprising: said impedance-increasing means comprising a cyclically operable switch and an energy-absorbing resistor in series with said cyclically operable switch and means to operate said cyclically operable switch, a rate of voltage rise limiting capacitor connected in parallel to said series combination of said cyclically operable switch and said energy-absorbing resistor, so that the time averaged impedance of said impedanceincreasing means increases as said cyclically operable switch is operated to have an increasing ratio of offswitch time.
Claim 3
Dependent Claim
17 words
The circuit breaker of claim 1 wherein said cyclically operable switch is a crossed field switch device.
Claim 4
Dependent Claim
24 words
The circuit breaker of claim 2 wherein a rate of voltage rise limiting capacitor is connected in parallel to said crossed field switching device.
Claim 5
Dependent Claim
58 words
The circuit breaker of claim 3 wherein a triggered gap switching device has reactance means in series therewith, said triggered gap switching device and said reactance means being connected in parallel to said capacitor in parallel to said crossed field switching device so that onswitching of said triggered gap causes resonant pulsing of said crossed field switching device.
Claim 6
Dependent Claim
24 words
The circuit breaker of claim 1 wherein said switch means comprises a triggered vacuum gap switch device having said energy-absorbing resistance in series therewith.
Claim 7
Dependent Claim
47 words
The circuit breaker of claim 5 wherein there are first and second triggered vacuum gap switch devices connected in parallel to each other through reactance means so that said second triggered vacuum gap switch device induces a current zero in said first triggered vacuum gap switch device.
Claim 8
Dependent Claim
71 words
The circuit breaker of claim 6 wherein said reactance means comprises capacitive means connected between said first and second triggered vacuum gap switch devices so that said capacitive means is charged by voltage drop in said circuit breaker and said charge on said capacitive means is discharged through one of said triggered vacuum gap switch devices to impress a current zero on the other of said triggered vacuum gap switch devices.
Claim 9
Dependent Claim
77 words
The process for increasing the impedance in a high voltage DC circuit breaker comprising the steps of: cyclically opening and closing a switch having a resistance in series therewith, through which switch and resistance pass the current in the circuit breaker to be interrupted, with increasing ratio of switch open time to switch closed time; and reactiVely damping current flow through the switch and the resistance to limit rate of voltage rise upon opening of the switch.
Claim 10
Dependent Claim
77 words
The process for increasing the impedance in a high voltage DC circuit breaker comprising the steps of: cyclically opening and closing a switch having a resistance in series therewith, through which switch and resistance pass the current in the circuit breaker to be interrupted, with increasing ratio of switch open time to switch closed time; and reactiVely damping current flow through the switch and the resistance to limit rate of voltage rise upon opening of the switch.
Claim 11
Dependent Claim
20 words
The process of claim 8 wherein said reactively limiting step comprises the step of capacitively limiting rate of voltage rise.
Claim 12
Dependent Claim
37 words
The process of claim 9 wherein closing is accomplished by the step of causing an electric discharge between spaced electrodes and switch opening is accomplished by the step of terminating the electric discharge between the spaced electrodes.
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) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |