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Patent US3883790A successfully refreshed from Google Patents.
US3883790A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Direct current power transmission
Assignee: ABB Norden Holding AB
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Filing: 1974-02-08
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Granted: 1975-05-13
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Expires: 1994-02-08
Abstract
Abstract A power transmission for high voltage direct current includes a direct current line and converter stations connected to the direct current line, with alternating current networks each connected to one of the converter stations. Each converter station includes at least two converters connected in parallel and is provided with a current control system to set the total current of the station as well as the current in the individual converters in accordance with a current order. Each station is provided with an arrangement for sensing the current and/or voltage on the d.c. line, which is connected to the current control system of the station and which reduces the current order set in the station in response to sudden interference in current and/or voltage. The station operating as an inverter is provided with an arrangement responsive to the disappearance of the current in one of the inverters of the station to limit the internal direct voltage of the other inverter to approximately zero.
Inventors
- 👤 Bertil Hammarlund
- 👤 Lars-Erik Juhlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:05
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/26; H02H7/268; H02J; H02J3/00; H02J3/36; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/162; H02M7/1623; H02M7/1626; H02M7/66; H02M7/68; H02M7/72; H02M7/75; H02M7/757; H02M7/7575; Y; Y02; Y02E; Y02E60/00; Y02E60/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
248 words
Power transmission for high voltage direct current comprising a direct current line (L) and convertor stations (LR, VR) connected thereto, each convertor station including a current control system, at least one station being a rectifier station and at least one station being an inverter station, the convertors in the inverter station being inverters, the convertors in the rectifier station being rectifiers, alternating current networks (V) at least one connected to each of said convertor stations, each convertor station comprising at least two convertors (1, 2) connected in parallel, each control system (6-8) including means to set the total current of the station as well as the current in the individual convertors in agreement with a predetermined current order (9), a telecommunication means (T) between said convertor stations for coordinating the total current of the stations, means for replacing said telecommunication line in case of a fault in it, said means comprising in each convertor station a means (11) to sense at least one of the magnitudes current or voltage on the d.c. line, means connected to said sensing means and to the current control system (8) of the station to reduce the current order set in the station in response to a sudden interference in at least one of the magnitudes current or voltage, and, in the inverter station, means (32, 42) responsive to current disappearance in one of the inverters of the station to reduce temporarily the internal direct voltage of the other inverter to approximately zero.
Claim 2
Dependent Claim
248 words
Power transmission for high voltage direct current comprising a direct current line (L) and convertor stations (LR, VR) connected thereto, each convertor station including a current control system, at least one station being a rectifier station and at least one station being an inverter station, the convertors in the inverter station being inverters, the convertors in the rectifier station being rectifiers, alternating current networks (V) at least one connected to each of said convertor stations, each convertor station comprising at least two convertors (1, 2) connected in parallel, each control system (6-8) including means to set the total current of the station as well as the current in the individual convertors in agreement with a predetermined current order (9), a telecommunication means (T) between said convertor stations for coordinating the total current of the stations, means for replacing said telecommunication line in case of a fault in it, said means comprising in each convertor station a means (11) to sense at least one of the magnitudes current or voltage on the d.c. line, means connected to said sensing means and to the current control system (8) of the station to reduce the current order set in the station in response to a sudden interference in at least one of the magnitudes current or voltage, and, in the inverter station, means (32, 42) responsive to current disappearance in one of the inverters of the station to reduce temporarily the internal direct voltage of the other inverter to approximately zero.
Claim 3
Dependent Claim
56 words
Power transmission according to claim 1, having in the rectifier station a line protection device (10) which includes means responsive to the cutting-out of one of the rectifiers in the station to disconnect said line protection device in the rectifier station (LR) for as long as the inverter station (VR) takes to alter its current order.
Claim 4
Dependent Claim
80 words
Power transmission according to claim 1, having in the rectifier station a line protection device (10) which includes means to perform a number of attempts at disconnection and connection in response to indication of a line fault, in which said current order reducing means of the rectifier station are responsive only after a number of attempts at disconnection and connection by the line protection device to reduce the current order of the current control system (8) of the rectifier station.
Claim 5
Dependent Claim
53 words
Power transmission according to claim 2, in which in the inverter station (VT), said means (32, 42) for temporarily reducing the voltage of an inverter which is not faulty to around zero is responsive to an excess of only the total current of the station over the current permissible for any remaining inverter.
Claim 6
Dependent Claim
42 words
Power transmission according to claim 4, in which the tele-communication means comprises a telecommunication line between the current systems of the stations, and means responsive to the cutting-out of said tele-communication line to increase the marginal current set in the inverter station.
Claim 7
Dependent Claim
36 words
Power transmission according to claim 1, including means responsive to the cutting-out of a rectifier in the rectifier station to increase the current order of the remaining rectifier to the current permitted for such remaining rectifier.
Claim 8
Dependent Claim
21 words
Power transmission according to claim 1, including means to reduce said current order to the maximum permissible for any remaining converter.
References Cited (Backward Citations)
US3431482A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |