US3663945A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for providing ac electrical energy at a preselected frequency
Assignee: Oklahoma State University
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Filing: 1970-09-04
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Granted: 1972-05-16
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Expires: 1990-09-04
Abstract
Abstract A method and apparatus for providing AC electrical energy at a preselected frequency including a driven AC generator having an externally excitable field, means connected to the generator field for exciting the field at the preselected frequency whereby the generated AC output is modulated at the preselected frequency, and rectifier means connected to the generator output by which the modulated generator output is rectified to obtain AC output at the preselected frequency, the frequency of the AC output being independent of the speed of rotation of the AC generator.
Inventors
- 👤 William L Hughes
- 👤 Hansel J Allison
- 👤 Ramachandra G Ramakumar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:48
CPC Classifications
H; H02; H02M; H02M5/00; H02M5/40; H02M5/42; H02M5/44; H02M5/443; H02M5/45
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
57 words
A generator, comprising: a stator having armature windings; a rotor rotatably supported relative to said stator, said rotor having field windings; a transformer secondary rotated with said rotor and having electrical connection to said generator field windings; and a transformer primary stationarily supported adjacent said stator, said transformer when energized by AC voltage providing generator field excitation.
Claim 2
Dependent Claim
57 words
A generator, comprising: a stator having armature windings; a rotor rotatably supported relative to said stator, said rotor having field windings; a transformer secondary rotated with said rotor and having electrical connection to said generator field windings; and a transformer primary stationarily supported adjacent said stator, said transformer when energized by AC voltage providing generator field excitation.
Claim 3
Dependent Claim
25 words
A generator according to claim 1 including rectifier means affixed to said rotor having electrical connection to said transformer secondary and to said field windings.
Claim 4
Dependent Claim
69 words
A generator according to claim 1 including: means of exciting said transformer primary and thereby said generator field at a preselected frequency whereby said stator windings provide AC energy modulated at the preselected frequency; and rectifier means having a power input, and a power output, the power input being connected to said generator, the modulated output of said generator being rectified to provide AC energy at the preselected frequency.
Claim 5
Dependent Claim
27 words
Apparatus for providing AC electrical energy at a preselected frequency according to claim 3 in which said rectifier means is controlled in synchronization with the preselected frequency.
Claim 6
Dependent Claim
32 words
Apparatus for providing AC electrical energy at a preselected frequency according to claim 3 in which said rectifier means is controlled in response to the current flow at the rectifier means output.
Claim 7
Dependent Claim
55 words
Apparatus for providing AC electrical energy at a preselected frequency according to claim 5 including a current transformer means in series with said rectifier means power output, and means controlling said rectifier means in response to detected current flow in said current transformer to switch said rectifier means when the detected current flow is minimum.
Claim 8
Dependent Claim
78 words
Apparatus for providing AC electrical energy at a preSelected frequency according to claim 3 in which said AC generator is a three phase generator having three power output circuits each providing AC energy at a frequency higher than the preselected frequency and in equally spaced phased relationship and including: a full wave rectifier means connected to each of said three power output, said full wave power outputs being connected in series with said controlled rectifier means power input.
Claim 9
Dependent Claim
83 words
Apparatus for providing AC electrical energy at a preselected frequency according to claim 3 in which said AC generator is a three phase generator having three power output circuits each providing AC energy at a frequency higher than the preselected frequency and in equally spaced phased relationship, and in which the three power output circuits are connected in series with two of the power output circuits reversed, the seriesed connection providing said generator AC energy connected to said controlled rectifier means power input.
Claim 10
Dependent Claim
24 words
Apparatus for providing AC electrical energy at a preselected frequency according to claim 3 in which said rectifier means is a controlled rectifier means.
Claim 11
Dependent Claim
63 words
Apparatus for providing AC electrical energy according to claim 3 in which said generator includes two electrically and magnetically separated stator-armature portions and two electrically and magnetically separated rotor-fields rotated by the same shaft, and wherein a separate rectifier means is connected to each said stator-armature, the outputs of the rectifier means being combined to provide electrical energy output at the preselected frequency.
Claim 12
Dependent Claim
71 words
Apparatus for providing AC electrical energy according to claim 10 in which one of said generator fields is modulated by a voltage signal defined by the relationship A + B sin wt and the other of said generator fields is modulated by a voltage signal defined by the relationship - A + B sin wt, wherein ''''A'''' is a DC voltage component and ''''B sin wt'''' is an AC voltage component.
Claim 13
Dependent Claim
79 words
A generator for providing AC electrical energy at a preselected frequency, comprising: a rotated shaft; first and second electrically and magnetically separated rotor fields rotated by said shaft; first and second electrically and magnetically separated stator-armatures positioned adjacent said first and second rotor-fields respectively; means of modulating said fields at the preselected frequency; and separate rectifier means connected to each said stator-armature, the outputs of the rectifier means being combined to provide electrical energy output at the preselected frequency.
Claim 14
Dependent Claim
79 words
A generator for providing AC electrical energy at a preselected frequency, comprising: a rotated shaft; first and second electrically and magnetically separated rotor fields rotated by said shaft; first and second electrically and magnetically separated stator-armatures positioned adjacent said first and second rotor-fields respectively; means of modulating said fields at the preselected frequency; and separate rectifier means connected to each said stator-armature, the outputs of the rectifier means being combined to provide electrical energy output at the preselected frequency.
Claim 15
Dependent Claim
70 words
Apparatus for providing AC electrical energy according to claim 12 in which one of said generator fields is modulated by a voltage signal defined by the relationship A + B sin wt and the other said generator fields is modulated by a voltage signal defined by the relationship - A + B sin wt, wherein ''''A'''' is a DC voltage component and ''''B sin wt'''' is an AC voltage component.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |