US3668489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency doubler motor drive and motor
Assignee: General Electric Co
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Filing: 1971-04-16
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Granted: 1972-06-06
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Expires: 1991-04-16
Abstract
Abstract A frequency doubler induction motor drive circuit supplied from a line frequency power source for driving a two-pole induction motor at 7,200 rpm. The drive circuit supplies a 120 Hz waveform to the motor and eliminates the expense of rectifiers and smoothing filters. The crossover points of the 60 Hz waveform are detected, and a gating and timing circuit applies gating pulses to suitably connected silicon controlled rectifiers at the maximum points of the 60 Hz waveform to produce the 120 Hz waveform.
Inventors
- 👤 David M Erdman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:46
CPC Classifications
H; H02; H02P; H02P27/00; H02P27/04; H02P27/06
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
224 words
A frequency doubler induction motor drive for supplying drive power to a single phase induction motor at a frequency which is twice that of a single phase a.c. power source, and having first and second line terminals; the motor having first, second and third motor terminals, a first stator winding connected between the first and second motor terminals, and a second stator winding connected between the secOnd and third motor terminals, said drive comprising:means for connecting said first line terminal to the second motor terminal; a first switching circuit comprising first and second oppositely poled, parallel-connected controlled rectifiers; means for connecting said first switching circuit between said second line terminal and the first motor terminal; a second switching comprising third and fourth oppositely poled, parallel-connected controlled rectifiers; means for connecting said second switching circuit between said second line terminal and the third motor terminal; a commutating capacitor connected between the first and third motor terminals; and logic means for generating gating pulses for rendering each controlled rectifier conducting only during a different quarter cycle of each cycle of the a.c. power source so that four flux reversals occur in the first and second stator windings during each cycle of said a.c. power source, whereby the induction motor is supplied with drive power having a frequency which is twice that of the a.c. power source.
Claim 2
Dependent Claim
224 words
A frequency doubler induction motor drive for supplying drive power to a single phase induction motor at a frequency which is twice that of a single phase a.c. power source, and having first and second line terminals; the motor having first, second and third motor terminals, a first stator winding connected between the first and second motor terminals, and a second stator winding connected between the secOnd and third motor terminals, said drive comprising:means for connecting said first line terminal to the second motor terminal; a first switching circuit comprising first and second oppositely poled, parallel-connected controlled rectifiers; means for connecting said first switching circuit between said second line terminal and the first motor terminal; a second switching comprising third and fourth oppositely poled, parallel-connected controlled rectifiers; means for connecting said second switching circuit between said second line terminal and the third motor terminal; a commutating capacitor connected between the first and third motor terminals; and logic means for generating gating pulses for rendering each controlled rectifier conducting only during a different quarter cycle of each cycle of the a.c. power source so that four flux reversals occur in the first and second stator windings during each cycle of said a.c. power source, whereby the induction motor is supplied with drive power having a frequency which is twice that of the a.c. power source.
Claim 3
Dependent Claim
113 words
A frequency doubler induction motor drive as defined in claim 1 wherein said controlled rectifiers comprise silicon controlled rectifiers each having a gate electrode; and wherein said logic means comprises:means for generating complementary first and second trains of said gating pulses, each of said gating pulses having a pulse width equal to one-half cycle of the a.c. power source and beginning and ending at a peak voltage of the a.c power source; means for applying said first train of gating pulses to the gate electrodes of said first and second controlled rectifiers; and means for applying said second train of gating pulses to the gate electrodes of said third and fourth controlled rectifiers.
Claim 4
Dependent Claim
136 words
A frequency doubler induction motor drive as defined in claim 2 wherein said logic means further comprises:means for generating a train of control pulses corresponding to each occurrence of zero voltage of the a.c. power source; means responsive to said control pulses for generating a first train of logic pulses each having a pulse width equal to one-half cycle of the a.c. power source and beginning and ending at the zero voltage times of the a.c. power source; means responsive to said control pulses and including delay means for generating a second train of logic pulses each having a pulse width equal to one quarter cycle of the a.c. power source; and logic gates responsive to said first and second trains of logic pulses for producing said complementary first and second trains of said gating pulses.
Claim 5
Dependent Claim
203 words
A frequency doubler motor drive for supplying drive power to a motor stator at a frequency which is twice that of an a.c. power source and having first and second line terminals; first, second and third motor terminals; a first stator winding connected between said first and second motor terminals; and a second stator winding connected between said second and third motor terminals, said drive also having: means for connecting said first line terminal to said second motor terminal; a first switching circuit comprising bilateral switching means; means for connecting said first switching circuit between said second line terminal and said first motor terminal; a second switching circuit comprising bilateral switching means; means for connecting said second switching circuit between said second line terminal and said third motor terminal; and logic means for generating gating pulses for rendering the bilateral switching means conducting only during preselected portions of each cycle of applied a.c. power so that flux reversals occur in the first and second stator winding during each cycle of applied a.c. power; whereby a.c. power impressed upon the bilateral switching means may be supplied to the motor as drive power having a frequency which is twice that of the a.c. power source.
Claim 6
Dependent Claim
203 words
A frequency doubler motor drive for supplying drive power to a motor stator at a frequency which is twice that of an a.c. power source and having first and second line terminals; first, second and third motor terminals; a first stator winding connected between said first and second motor terminals; and a second stator winding connected between said second and third motor terminals, said drive also having: means for connecting said first line terminal to said second motor terminal; a first switching circuit comprising bilateral switching means; means for connecting said first switching circuit between said second line terminal and said first motor terminal; a second switching circuit comprising bilateral switching means; means for connecting said second switching circuit between said second line terminal and said third motor terminal; and logic means for generating gating pulses for rendering the bilateral switching means conducting only during preselected portions of each cycle of applied a.c. power so that flux reversals occur in the first and second stator winding during each cycle of applied a.c. power; whereby a.c. power impressed upon the bilateral switching means may be supplied to the motor as drive power having a frequency which is twice that of the a.c. power source.
Claim 7
Dependent Claim
101 words
A frequency doubler motor drive as defined in claim 4 wherein said bilateral switching means comprise solid state devices each having a gate eleCtrode, and wherein said logic means comprises: means for generating complementary first and second trains of said gating pulses, each of said gating pulses having a pulse substantially equal in width to one-half cycle of the a.c. power source and beginning and ending at a peak voltage of said a.c. power source; and means for applying said first and second trains of gating pulses respectively to the gate electrodes of said first and second bilateral switching means respectively.
Claim 8
Dependent Claim
140 words
A frequency doubler motor drive as defined in claim 5 wherein said logic means further comprises: means for generating a train of control pulses corresponding to each occurrence of zero voltage of the a.c. power source; means responsive to said control pulses for generating a first train of logic pulses each having a pulse substantially equal in width to one-half cycle of the a.c. power source and beginning and ending at the zero voltage times of the a.c. power source; means responsive to said control pulses and including delay means for generating a second train of logic pulses each having a pulse substantially equal in width to one quarter cycle of the a.c. power source; and logic gates responsive to said first and second trains of logic pulses for producing said complementary first and second trains of said gating pulses.
Claim 9
Dependent Claim
169 words
A dynamoelectric machine package comprising: a frequency doubler motor drive having input termination means for connection with a source of a.c. power, an output stage, and output termination means connected to the output stage; the output stage comprising a pair of closely coupled windings; and a dynamoelectric machine magnetic core; said motor drive comprising first bilateral switching means connected between an input termination means and an output termination means, and second bilateral switching means connected between another input termination means and another output termination means; and logic means for generating gating pulses for rendering the bilateral switching means conducting only during preselected portions of each cycle of applied a.c. power so that flux reversals may occur in the pair of closely coupled windings during each cycle of a.c. power applied to the bilateral switching means thereby to provide drive power having a frequency which is twice that of the a.c. power source for utilization in maintaining a desired cyclically varying magnetic flux distribution in the dynamoelectric machine magnetic core.
Claim 10
Dependent Claim
169 words
A dynamoelectric machine package comprising: a frequency doubler motor drive having input termination means for connection with a source of a.c. power, an output stage, and output termination means connected to the output stage; the output stage comprising a pair of closely coupled windings; and a dynamoelectric machine magnetic core; said motor drive comprising first bilateral switching means connected between an input termination means and an output termination means, and second bilateral switching means connected between another input termination means and another output termination means; and logic means for generating gating pulses for rendering the bilateral switching means conducting only during preselected portions of each cycle of applied a.c. power so that flux reversals may occur in the pair of closely coupled windings during each cycle of a.c. power applied to the bilateral switching means thereby to provide drive power having a frequency which is twice that of the a.c. power source for utilization in maintaining a desired cyclically varying magnetic flux distribution in the dynamoelectric machine magnetic core.
Claim 11
Dependent Claim
48 words
The structure of claim 7 wherein the output stage closely coupled windings are wound on the dynamoelectric machine core and closely coupled thereon, whereby flux reversals occurring in the pair of closely coupled windings maintain the desired cyclically varying magnetic flux distribution in the dynamoelectric machine magnetic core.
Claim 12
Dependent Claim
36 words
The structure of claim 8 wherein at least one motor winding is accommodated on the dynamolelectric machine core and the closely coupled windings are connected in parallel circuit relation with the at least one motor winding.
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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) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |