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US3878448A
Expired / Lapsed
US
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Control circuit for a thyristor rectifier
Assignee: ABB Norden Holding AB
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Filing: 1973-06-05
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Granted: 1975-04-15
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Expires: 1993-06-05
Abstract
Abstract A thyristor rectifier for high voltages includes a number of seriesconnected thyristors each of which has a control device. A control circuit for the whole rectifier includes a control pulse transmitter and a signal emitter for each thyristor which emits an indicating signal when the voltage in the conducting direction of the relevant thyristor reaches a predetermined value. The control circuit includes an input circuit to which signals for ignition of the whole thyristor rectifier are connected. The signal emitters and input circuit are connected to an AND-gate. The different signal emitters are connected to the AND-gate by an OR-gate. The OR-gate is connected to the AND-gate by a flip-flop and the output side of the AND-gate is connected to the flip-flop in such a way that a signal from the OR-gate energizes the flipflop while a signal from the AND-gate switches it off.
Inventors
- 👤 Per-Olof Jackson
- 👤 Lars-Erik Juhlin
- 👤 Brent Ostlund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:37
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/08; H02M1/088; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/19
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
119 words
Thyristor rectifier for high voltage comprising a plurality of series-connected thyristors (10-1n), each provided with a control device (1) and a control circuit for the whole rectifier, the control devices being controlled from a control pulse transmitter (8) in the control circuit and provided with a signal emitter which emits an indicating signal when the voltage in the conducting direction of the relevant thyristor reaches a certain value and the control circuit comprising an input circuit (20) to which signals for ignition of the whole thyristor rectifier are connected, in which an AND-gate (6) connects said signal emitter and said input circuit to said control pulse transmitter, and an OR-gate (3) connects the different signal emitters to the ANDgate.
Claim 2
Dependent Claim
119 words
Thyristor rectifier for high voltage comprising a plurality of series-connected thyristors (10-1n), each provided with a control device (1) and a control circuit for the whole rectifier, the control devices being controlled from a control pulse transmitter (8) in the control circuit and provided with a signal emitter which emits an indicating signal when the voltage in the conducting direction of the relevant thyristor reaches a certain value and the control circuit comprising an input circuit (20) to which signals for ignition of the whole thyristor rectifier are connected, in which an AND-gate (6) connects said signal emitter and said input circuit to said control pulse transmitter, and an OR-gate (3) connects the different signal emitters to the ANDgate.
Claim 3
Dependent Claim
60 words
Thyristor rectifier according to claim 1, in which a flip-flop (4) connects said OR-gate (3) to said AND-gate (6) and means is provided connecting the output side of said AND-gate to said flip-flop in such a way that a signal from the OR-gate causes the flip-flop to be energized, whereas the subsequent signal from the AND-gate switches the flip-flop off.
Claim 4
Dependent Claim
19 words
Thyristor rectifier according to claim 1, including a delay circuit (5) connecting said OR-gate (3) to said AND-gate (6).
Claim 5
Dependent Claim
21 words
Thyristor rectifier according to claim 1, including a pulse former (7) connecting said AND-gate (6) to the control pulse transmitter (8).
Claim 6
Dependent Claim
23 words
Thyristor rectifier according to claim 4, in which the pulse former includes means to emit control pulses with a given length and frequency.
Claim 7
Dependent Claim
44 words
Thyristor rectifier according to claim 1, in which said input circuit comprises an OR-gate (20), to which the normal ignition signal (21) of the thyristor rectifier, as well as the ignition signal from a recovery protection device (22) for the thyristors (10-1n) are connected.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |