Patent US4032824A successfully refreshed from Google Patents.
US4032824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variable-speed 3-phase drive
Assignee: Siemens AG
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Filing: 1975-12-15
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Granted: 1977-06-28
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Expires: 1995-12-15
Abstract
Abstract A variable-speed three-phase drive is disclosed. The drive includes a switchable, undersynchronous converter cascade for driving two mechanically coupled asynchronous motors which have slip ring rotors and which can be connected separately to a three-phase network. The slip ring rotors of the two asynchronous motors are connected, respectively, with the three-phase terminals of different uncontrolled rectifiers. The latter two rectifiers, together with two inverters and two other rectifiers, are arranged in a ring circuit in such a manner that two rectifiers are always followed by an inverter. In accord with the invention, a switch is provided for connecting the three-phase terminals of the two rectifiers which are disposed on the respective cathode sides of the two inverters, and for also connecting the three-phase terminals of the two rectifiers which are disposed on the respective anode sides of the two inverters.
Inventors
- 👤 Harald Elger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:40
CPC Classifications
H; H02; H02P; H02P5/00; H02P5/74; H02P5/747
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
225 words
A variable-speed three-phase drive for use with a three-phase network, said drive comprising: first and second asynchronous motors each adapted to be connected to said network and each having a slip ring rotor; first and second uncontrolled rectifiers, each of said rectifiers having a DC terminal connected to a DC terminal of the other and each having three-phase terminals connected to the rotor of a different one of said motors; third and fourth uncontrolled rectifiers, each of said rectifiers having a DC terminal connected to a DC terminal of the other and each having three-phase terminals; first and second inverters each having three-phase terminals adapted to be connected to said network, said first inverter having DC terminals which are connected with respective DC terminals of said first and said third uncontrolled rectifiers and said second inverter having DC terminals which are connected with respective DC terminals of said second and fourth uncontrolled rectifiers, whereby said first and second inverters and said first and second and said third and fourth uncontrolled rectifiers form a ring circuit; and switch means for connecting together the three-phase terminals of the two uncontrolled rectifiers connected to the respective anode sides of said first and second inverters and for connecting together the three-phase terminals of the two uncontrolled rectifiers connected to the respective cathode sides of said first and second inverters.
Claim 2
Dependent Claim
225 words
A variable-speed three-phase drive for use with a three-phase network, said drive comprising: first and second asynchronous motors each adapted to be connected to said network and each having a slip ring rotor; first and second uncontrolled rectifiers, each of said rectifiers having a DC terminal connected to a DC terminal of the other and each having three-phase terminals connected to the rotor of a different one of said motors; third and fourth uncontrolled rectifiers, each of said rectifiers having a DC terminal connected to a DC terminal of the other and each having three-phase terminals; first and second inverters each having three-phase terminals adapted to be connected to said network, said first inverter having DC terminals which are connected with respective DC terminals of said first and said third uncontrolled rectifiers and said second inverter having DC terminals which are connected with respective DC terminals of said second and fourth uncontrolled rectifiers, whereby said first and second inverters and said first and second and said third and fourth uncontrolled rectifiers form a ring circuit; and switch means for connecting together the three-phase terminals of the two uncontrolled rectifiers connected to the respective anode sides of said first and second inverters and for connecting together the three-phase terminals of the two uncontrolled rectifiers connected to the respective cathode sides of said first and second inverters.
Claim 3
Dependent Claim
62 words
A drive in accordance with claim 1 in which: the anode of said first inverter is connected to said first uncontrolled rectifier and the cathode of said first inverter to said third uncontrolled rectifier; and the anode of said second inverter is connected to said fourth uncontrolled rectifier and the cathode of said first inverter is connected to said second uncontrolled rectifier.
Claim 4
Dependent Claim
46 words
A drive in accordance with claim 2 in which: each of said uncontrolled rectifiers is a three-phase bridge circuit; and said switch means interconnects the three phases of said first and fourth uncontrolled rectifiers and interconnects the three phases of said second and third uncontrolled rectifers.
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) | 1980-06-27 | 1980-12-27 | 1981-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-27 | 1984-12-27 | 1985-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-27 | 1988-12-27 | 1989-06-28 | $7700.00 | Window Closed / Lapsed |