Patent US4000464A successfully refreshed from Google Patents.
US4000464A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement for detecting ground leaks in the rotor circuit of a brushless synchronous machine excited by rotating rectifiers
Assignee: Siemens AG
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Filing: 1975-06-12
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Granted: 1976-12-28
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Expires: 1995-06-12
Abstract
Abstract The invention is directed to an arrangement for detecting ground leaks and includes two identical synchronous machines coupled to the rotor of a brushlessly excited synchronous machine. One of the identical machines is built as an outer-pole machine and the other as an inner-pole machine. The stator winding of the outer-pole machine is supplied with a constant direct current and its rotor winding is connected through a rectifier bridge to be between ground and the neutral point of the rotor of the brushlessly excited synchronous machine. The rectifier feeds the rotor winding of the inner-pole machine, and the voltage measured at the stator winding of the latter is a measure of the insulation resistance in the rotor circuit of the brushless synchronous machine.
Inventors
- 👤 Lothar Nussel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 09:23
CPC Classifications
H; H02; H02K; H02K19/00; H02K19/16; H02K19/36; G; G01; G01R; G01R31/00; G01R31/34
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
215 words
An arrangement for detecting ground leaks in the insulated rotor circuit of a brushless synchronous machine, the synchronous machine having a rotatable shaft and being excited by means of a rotating rectifier, the arrangement comprising: two identical synchronous machines arranged on the shaft of the brushless synchronous machine; one of said identical machines being built as an outer-pole machine and the other one of said identical machines being built as an inner-pole machine, said outer-pole machine having a stator winding and supply means for supplying a constant direct-current to said stator winding, said outer-pole machine further having a rotor winding wherein an alternating rotor current is developed, said rotor winding of the outer-pole machine being electrically connected to the insulation resistance of the rotor circuit of the brushless synchronous machine; rectifier means for rectifying the alternating-current of said rotor of said outer-pole machine; the other one of said identical machines being built as an inner-pole machine having a stator winding and having a rotor winding connected to said rectifier means for receiving said rotor current rectified by said rectifier means whereby a voltage is induced in said stator winding of said inner-pole machine which is dependent upon the current in the insulation of said brushless synchronous machine; and, measuring means for measuring said last-mentioned voltage.
Claim 2
Dependent Claim
215 words
An arrangement for detecting ground leaks in the insulated rotor circuit of a brushless synchronous machine, the synchronous machine having a rotatable shaft and being excited by means of a rotating rectifier, the arrangement comprising: two identical synchronous machines arranged on the shaft of the brushless synchronous machine; one of said identical machines being built as an outer-pole machine and the other one of said identical machines being built as an inner-pole machine, said outer-pole machine having a stator winding and supply means for supplying a constant direct-current to said stator winding, said outer-pole machine further having a rotor winding wherein an alternating rotor current is developed, said rotor winding of the outer-pole machine being electrically connected to the insulation resistance of the rotor circuit of the brushless synchronous machine; rectifier means for rectifying the alternating-current of said rotor of said outer-pole machine; the other one of said identical machines being built as an inner-pole machine having a stator winding and having a rotor winding connected to said rectifier means for receiving said rotor current rectified by said rectifier means whereby a voltage is induced in said stator winding of said inner-pole machine which is dependent upon the current in the insulation of said brushless synchronous machine; and, measuring means for measuring said last-mentioned voltage.
Claim 3
Dependent Claim
26 words
The arrangement of claim 1, said rectifier means being connected between said rotor winding of said outer-pole machine and said insulation of said brushless synchronous machine.
Claim 4
Dependent Claim
84 words
The arrangement of claim 1 wherein the brushless synchronous machine defines an electrical ground terminal and wherein the rotor circuit thereof includes a neutral node, said rectifier means being a rectified bridge having a pair of direct-current terminals and having a pair of alternating-current terminals, said rotor winding of said inner-pole machine being connected to said direct-current terminals and said rotor winding of said outer-pole machine being connected through said alternating-current terminals between said ground and said neutral node of said brushless synchronous machine.
Claim 5
Dependent Claim
18 words
The arrangement of claim 3, each of said two identical synchronous machines being configured as a single-phase machine.
Claim 6
Dependent Claim
18 words
The arrangement of claim 1, each of said two identical synchronous machines being configured as a single-phase machine.
Claim 7
Dependent Claim
22 words
The arrangement of claim 1, said identical synchronous machine being coupled to the end of said shaft of said brushless synchronous machine.
References Cited (Backward Citations)
SU178411A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-12-28 | 1980-06-28 | 1980-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-28 | 1984-06-28 | 1984-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-28 | 1988-06-28 | 1988-12-28 | $7700.00 | Window Closed / Lapsed |