US4328447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
DC Motor speed regulator
Assignee: General Electric Co
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Filing: 1980-07-29
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Granted: 1982-05-04
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Expires: 2000-07-29
Abstract
Abstract A speed regulating circuit which regulates motor speed without the use of a speed feedback signal by adjusting the magnitude of motor current so as to maintain a predetermined relationship between motor voltage and current. A function generator generates a current reference signal as a function of motor terminal voltage. The relationship between terminal voltage and motor current is established by curve fitting of the motor volt-amp family of curves for constant motor speeds. The current reference signal controls a motor current control circuit, preferably a time ratio or chopper circuit in order to adjust motor current and to regulate motor speed. A closed loop current control loop is associated with the chopper circuit for adjusting motor current to the current reference value.
Inventors
- 👤 Richard K. Davis
- 👤 Joe C. Lambert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:41
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; H02P7/2913
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
182 words
An open-loop speed regulator system for regulating the rotational speed of a rotor of a DC electric motor having series connected armature and field windings including controllable switching means for periodically interconnecting the motor and a DC source, said control system comprising: (a) gating control means for controlling the duty factor of the switching means as a function of a current command signal, said gating control means being connected to supply periodic ON and OFF commands to the switching means for controlling said duty factor: (b) means for generating a first signal representative of current in the motor; (c) means for generating a second signal representative of terminal voltage appearing across the series combination of motor armature and field windings; (d) function generator means for receiving said second signal and for generating a third signal having a magnitude which is a predetermined function of the magnitude of said second signal; (e) means connected for summing said first signal and said third signal for generating said current command signal; and, (f) means for coupling said current command signal to said gating control means.
Claim 2
Dependent Claim
182 words
An open-loop speed regulator system for regulating the rotational speed of a rotor of a DC electric motor having series connected armature and field windings including controllable switching means for periodically interconnecting the motor and a DC source, said control system comprising: (a) gating control means for controlling the duty factor of the switching means as a function of a current command signal, said gating control means being connected to supply periodic ON and OFF commands to the switching means for controlling said duty factor: (b) means for generating a first signal representative of current in the motor; (c) means for generating a second signal representative of terminal voltage appearing across the series combination of motor armature and field windings; (d) function generator means for receiving said second signal and for generating a third signal having a magnitude which is a predetermined function of the magnitude of said second signal; (e) means connected for summing said first signal and said third signal for generating said current command signal; and, (f) means for coupling said current command signal to said gating control means.
Claim 3
Dependent Claim
25 words
The control system of claim 1 and including means for varying the magnitude of said second signal whereby the speed of the rotor is varied.
Claim 4
Dependent Claim
67 words
The control system of claim 2 wherein the relationship between said second signal and said third signal is defined by I=K.sub.1 V.sub.M +K.sub.2 V.sub.M.sup.N, wherein, I represents the magnitude of said third signal, K 1 and K 2 are constant multipliers determined by the electrical characteristics of the motor, V M represents the magnitude of said second signal, and N is a number between 2 and 5.
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) | 1985-05-03 | 1985-11-02 | 1986-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-03 | 1989-11-02 | 1990-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-03 | 1993-11-02 | 1994-05-04 | $7700.00 | Window Closed / Lapsed |