Patent US2026172A successfully refreshed from Google Patents.
US4030006A
Expired / Lapsed
US
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Speed controllable drive for an asynchronous motor
Assignee: Siemens AG
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Filing: 1975-04-10
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Granted: 1977-06-14
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Expires: 1995-04-10
Abstract
Abstract A speed controllable three phase drive including an asynchronous motor having a slip ring rotor which can be connected to a three phase network and a d.c. motor mechanically coupled to the asynchronous motor with the d.c. motor fed through an uncontrolled rectifier connected to the slip ring of the asynchronous motor has a controlled static converter in series with the uncontrolled rectifier and d.c. motor. In an alternate embodiment the d.c. motor is replaced by a static converter motor fed by a controlled inverter connected to the uncontrolled rectifier. The controlled static converter is coupled to the three phase network to result in a three phase drive with a greater speed range and a lower reactive power requirement as compared to subsynchronous static converter cascades.
Inventors
- 👤 Harald Elger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 13:17
CPC Classifications
H; H02; H02P; H02P27/00; H02P27/04; H02P27/048; H02P23/00; H02P23/0004; H02P27/045; H02P27/06; H02P2207/00; H02P2207/01
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
128 words
A speed controllable three phase drive comprising: a. an asychronous motor having a slip ring rotor; b. means for coupling the stator of said asynchronous motor to a three phase network; c. a three phase synchronous motor having its shaft mechanically coupled to the shaft of said asynchronous motor; d. an uncontrolled rectifier having its a.c. input coupled to the slip rings of said asynchronous motor; e. a controlled inverter made up of a plurality of controlled rectifiers in a bridge arrangement feeding said three phase synchronous motor with its a.c. output; and f. a controlled static converter having an a.c. input coupled to said three phase network, the d.c. terminals of said controlled static converter, said controlled inverter and said rectifier coupled in series with each other.
Claim 2
Dependent Claim
128 words
A speed controllable three phase drive comprising: a. an asychronous motor having a slip ring rotor; b. means for coupling the stator of said asynchronous motor to a three phase network; c. a three phase synchronous motor having its shaft mechanically coupled to the shaft of said asynchronous motor; d. an uncontrolled rectifier having its a.c. input coupled to the slip rings of said asynchronous motor; e. a controlled inverter made up of a plurality of controlled rectifiers in a bridge arrangement feeding said three phase synchronous motor with its a.c. output; and f. a controlled static converter having an a.c. input coupled to said three phase network, the d.c. terminals of said controlled static converter, said controlled inverter and said rectifier coupled in series with each other.
Claim 3
Dependent Claim
18 words
Apparatus according to claim 1 wherein said uncontrolled rectifier comprises a plurality of rectifiers in a bridge arrangement.
Claim 4
Dependent Claim
19 words
Apparatus according to claim 1 wherein said controlled static converter comprises a plurality of rectifiers in a bridge arrangement.
Claim 5
Dependent Claim
14 words
Apparatus according to claim 3 wherein said controlled converter is a line commutated converter.
Claim 6
Dependent Claim
29 words
Apparatus according to claim 1 and further including a choke in the series circuit making up the feed circuit for said means having the characteristic of a d.c. motor.
Claim 7
Dependent Claim
19 words
Apparatus according to claim 1 wherein said controlled static converter is coupled to three phase network through a transformer.
Claim 8
Dependent Claim
41 words
Apparatus according to claim 1 wherein said means coupling the stator of said asynchronous motor to the three phase network comprises a switch and further including an additional switch, independently operated, coupling said controlled static converter to said three phase network.
Claim 9
Dependent Claim
11 words
Apparatus according to claim 1 wherein said inverter is load controlled.
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) | 1980-06-13 | 1980-12-13 | 1981-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-06-13 | 1984-12-13 | 1985-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-06-13 | 1988-12-13 | 1989-06-14 | $7700.00 | Window Closed / Lapsed |