US3735226A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Constant torque and inertia control for armature current regulated dc motor with field weakening
Assignee: Westinghouse Electric Corp
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Filing: 1972-02-04
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Granted: 1973-05-22
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Expires: 1992-02-04
Abstract
Abstract Constant and acceleration torque (inertia) compensating signals are combined with armature current feedback to develop a current control signal for regulating the armature current of a direct current motor so that output torque both is kept constant for and weakened motor shunt fields, and during system speed changes.
Inventors
- 👤 J Pittner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:08
CPC Classifications
H; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/298; H02P7/2985
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
142 words
In combination with a motor control system for a direct current motor with field weakening where the motor field current is kept constant in a first regulation state when the motor CEMF is below rated value and the CEMF is kept constant in a second regulation state as speed increases to rated value, a reference signal responsive to a speed signal for producing a first reference signal during said first regulation state and proportional to speed during said second regulation state; an inertial compensation generator responsive to said speed signal and to said first reference signal for producing an acceleration torque signal; means for translating said first reference signal to a constant torque signal; and means for combining said acceleration torque signal and said constant torque signal with a signal representing armature current to produce a current control signal for the system.
Claim 2
Dependent Claim
142 words
In combination with a motor control system for a direct current motor with field weakening where the motor field current is kept constant in a first regulation state when the motor CEMF is below rated value and the CEMF is kept constant in a second regulation state as speed increases to rated value, a reference signal responsive to a speed signal for producing a first reference signal during said first regulation state and proportional to speed during said second regulation state; an inertial compensation generator responsive to said speed signal and to said first reference signal for producing an acceleration torque signal; means for translating said first reference signal to a constant torque signal; and means for combining said acceleration torque signal and said constant torque signal with a signal representing armature current to produce a current control signal for the system.
Claim 3
Dependent Claim
43 words
The combination of claim 1 wherein said inertial compensation generator comprises first means for differentiating said speed signal and second means for producing an acceleration torque reference signal proportional to the product of said first reference signal and the derivative of system speed.
Claim 4
Dependent Claim
41 words
The combination of claim 1 wherein said reference signal generator includes first and second circuits for producing a constant signal and a signal proportional to speed, respectively, and a crossover circuit responsive to these signals for producing said first reference signal.
Claim 5
Dependent Claim
38 words
The combination of claim 3 wherein said cross-over circuit includes two diodes having first electrodes coupled to said first and second circuits, respectively, the second electrode of said diodes forming a junction to produce said first reference signal.
Claim 6
Dependent Claim
125 words
In combination with a direct current motor control system with field weakening wherein a current regulator maintains armature current proportional to a current reference signal and a field regulator establishes first regulation of motor field current when the motor CEMF is below rated value and second regulation for constant CEMF as motor speed increases to rated value, a first circuit for translating a system speed signal and a constant signal into a first reference signal during first regulation and proportional to speed during second regulation, means responsive to said first reference signal for producing constant torque and acceleration torque reference signals; and means for combining said constant torque and acceleration torque reference signals with said armature current signal to product a system current control signal.
Claim 7
Dependent Claim
125 words
In combination with a direct current motor control system with field weakening wherein a current regulator maintains armature current proportional to a current reference signal and a field regulator establishes first regulation of motor field current when the motor CEMF is below rated value and second regulation for constant CEMF as motor speed increases to rated value, a first circuit for translating a system speed signal and a constant signal into a first reference signal during first regulation and proportional to speed during second regulation, means responsive to said first reference signal for producing constant torque and acceleration torque reference signals; and means for combining said constant torque and acceleration torque reference signals with said armature current signal to product a system current control signal.
Claim 8
Dependent Claim
29 words
The combination of claim 5 wherein said acceleration torque signal is produced as the function of the product of said first reference signal and the derivative of system speed.
Claim 9
Dependent Claim
21 words
The combination of claim 5 wherein said constant torque signal is produced as a linear function of said first reference signal.
Claim 10
Dependent Claim
41 words
The combination of claim 7 wherein said first circuit includes a diode comparator responsive to a constant signal and a signal proportional to speed and for producing a constant reference signal during first regulation and proportional to speed during second regulation.
Claim 11
Dependent Claim
30 words
The combination of claim 6 wherein said acceleration torque signal is defined by the relationship: TM KpJDW/dt during first regulation and is proportional to TM K'' pW(JdW/dt) during second regulation.
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) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |