Patent US3725742A successfully refreshed from Google Patents.
US3725742A
Expired / Lapsed
US
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Static circuit breaker
Assignee: General Electric Co
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Filing: 1972-02-23
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Granted: 1973-04-03
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Expires: 1992-02-23
Abstract
Abstract Disclosed is a 3-phase static circuit breaker including three phase switches, each switch including a pair of power thyristors connected in inverse parallel relationship with one another and a common commutation circuit. A common surge suppressing circuit for all the switches is also provided in the static circuit breaker.
Inventors
- 👤 E Pollard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:40
CPC Classifications
H; H02; H02H; H02H9/00; H02H9/04; H02H7/00; H02H7/10; H02H7/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
185 words
For use in a power system including an AC power source and a load, a bidirectional switch for conducting current between the source and the load and for interrupting the flow of such current upon command, said switch comprising: a. first and second thyristors connected in inverse parallel relationship with one another to form first and second load current conducting paths, each of said thyristors including an anode and a cathode; b. a first unipolarity conducting element having its anode connected to the anode of said first thyristor; c. a second unipolarity conducting element having its anode connected to the anode of said second thyristor, the cathodes of said first and second elements being connected to one another at a first point; d. a third unipolarity conducting element having its cathode connected to the cathode of said second thyristor; e. a fourth unipolarity conducting element having its cathode connected to the cathode of said first thyristor, the anodes of said third and fourth elements being connected to one another at a second point; and f. a commutation circuit connected between said first and second points.
Claim 2
Dependent Claim
185 words
For use in a power system including an AC power source and a load, a bidirectional switch for conducting current between the source and the load and for interrupting the flow of such current upon command, said switch comprising: a. first and second thyristors connected in inverse parallel relationship with one another to form first and second load current conducting paths, each of said thyristors including an anode and a cathode; b. a first unipolarity conducting element having its anode connected to the anode of said first thyristor; c. a second unipolarity conducting element having its anode connected to the anode of said second thyristor, the cathodes of said first and second elements being connected to one another at a first point; d. a third unipolarity conducting element having its cathode connected to the cathode of said second thyristor; e. a fourth unipolarity conducting element having its cathode connected to the cathode of said first thyristor, the anodes of said third and fourth elements being connected to one another at a second point; and f. a commutation circuit connected between said first and second points.
Claim 3
Dependent Claim
35 words
The bidirectional switch as specified in claim 1 wherein said commutation circuit comprises; i. a third thyristor connected in series with a capacitor, the cathode of said third thyristor being connected to said second point.
Claim 4
Dependent Claim
31 words
The bidirectional switch as specified in claim 2 additionally comprising: g. first impedance means connected in said first conducting path; and h. second impedance means connected in said second conducting path.
Claim 5
Dependent Claim
17 words
The bidirectional switch as specified in claim 3 wherein said first and second impedance means are inductors.
Claim 6
Dependent Claim
49 words
The bidirectional switch as specified in claim 3 wherein said first inductor is connected between the anode of said first thyristor and the cathode of said third element and wherein said second inductor is connected between the anode of said second thyristor and the cathode of said fourth element.
Claim 7
Dependent Claim
92 words
The bidirectional switch as specified in claim 1 additionally comprising; g. a fifth unipolarity conducting element diode whose anode is connected to the cathode of said second thyristor; h. a sixth unipolarity conducting element whose anode is connected to the cathode of said first thyristor and whose cathode is connected to the cathode of said fifth element at a third point; i. a seventh unipolarity conducting element whose cathode is connected to said second point; and j. surge suppressing means connected between said third point and the anode of said seventh Element.
Claim 8
Dependent Claim
38 words
The bidirectional switch as specified in claim 5 wherein said surge suppressing means comprises; i. an energy storage element and ii. an energy dissipating element, said energy dissipating element being connected in shunt with said energy storage element.
Claim 9
Dependent Claim
25 words
The bidirectional switch as specified in claim 6 wherein said energy storage element is a capacitor and wherein said energy dissipating element is a resistor.
Claim 10
Dependent Claim
159 words
The bidirectional switch as specified in claim 2 additionally comprising; g. a first inductor connected in said first conducting path between the anode of said first thyristor and the cathode of said third element; h. a second inductor connected in said second conducting path between the anode of said second thyristor and the cathode of said fourth element; i. a fifth unipolarity conducting element whose anode is connected to the cathode of said second thyristor; j. a sixth unipolarity conducting element whose anode is connected to the cathode of said first thyristor and whose cathode is connected to the cathode of said fifth element at a third point; k. a seventh unipolarity conducting element whose cathode is connected to said second point; l. surge suppressing means connected between said third point and the anode of said seventh element, said surge suppressing means comprising: i. a capacitor; and ii. a resistor, said resistor being connected in shunt with said capacitor.
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |