US3657622A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control for adjusting and regulating the speed of an electric motor
Assignee: REULAND ELECTRIC Co INDUSTRY
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Filing: 1970-04-30
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Granted: 1972-04-18
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Expires: 1990-04-30
Abstract
Abstract Control means for adjusting and regulating the speed of an alternating current electric motor of the wound rotor type, wherein the motor stator is connected to an alternating current power line, and the circuit leads of the rotor winding are connected through gate controlled solid-state switching elements which are operable to rapidly close and open the rotor winding circuit so as to produce pulsed power, and by varying the duration of the produced pulses the average torque will be varied and the motor speed regulated. The gate controlled switching elements are automatically controlled in response to changes in a sensed signal resulting from a comparison of a speed sensitive transducer output voltage with a reference voltage which can be adjustably set according to the desired motor speed. Changes in the reference voltage thus provide for adjustment of the motor speed, while the variations of the transducer voltage in relation to the adjusted reference voltage provide for speed regulation at the selected motor speed.
Inventors
- 👤 Frank E Reuland
- 👤 Richard R Palm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:41
CPC Classifications
H; H02; H02P; H02P25/00; H02P25/16; H02P25/24; H02P25/26
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
181 words
Speed control means for an electric motor having a stator field winding and a power delivery rotor with a winding in magnetically coupled relation with the stator field winding, comprising: a. gating means connected in circuit with said rotor winding, and being selectively operable to connect said rotor winding so as to be short-circuited and open-circuited, said gating means including a gate control triggering circuit; b. means for controlling said triggering circuit in response to a sensed signal which varies as a function of rotor speed changes, said means comprising integrator means connected with the motor rotor circuit for providing output pulses proportional to rotor power and which are determinative of the conduction angle of the rotor winding during half-cycle periods; and electronic comparator means having an output controllably connected with said triggering circuit, said comparator having one input connected to receive the output of said integrator, and another input connected to a DC reference voltage adjustable according to the desired motor speed; and c. means for resetting the integrator means to zero on each half-cycle of the sensed rotor signal.
Claim 2
Dependent Claim
181 words
Speed control means for an electric motor having a stator field winding and a power delivery rotor with a winding in magnetically coupled relation with the stator field winding, comprising: a. gating means connected in circuit with said rotor winding, and being selectively operable to connect said rotor winding so as to be short-circuited and open-circuited, said gating means including a gate control triggering circuit; b. means for controlling said triggering circuit in response to a sensed signal which varies as a function of rotor speed changes, said means comprising integrator means connected with the motor rotor circuit for providing output pulses proportional to rotor power and which are determinative of the conduction angle of the rotor winding during half-cycle periods; and electronic comparator means having an output controllably connected with said triggering circuit, said comparator having one input connected to receive the output of said integrator, and another input connected to a DC reference voltage adjustable according to the desired motor speed; and c. means for resetting the integrator means to zero on each half-cycle of the sensed rotor signal.
Claim 3
Dependent Claim
141 words
Speed control means for an electric motor having a stator field winding and a power delivery rotor with a winding in magnetically coupled relation with the stator field winding, comprising: a. gating means connected in circuit with said rotor winding, and being selectively operable to connect said rotor winding so as to be short-circuited and open-circuited, said gating means including a gate control triggering circuit; and b. means for controlling said triggering circuit comprising a DC reference voltage adjustable to preset the motor speed to a desired value, a DC voltage analog of the motor speed, and a differential lead-lag network having inputs connected to said reference voltage and said analog voltage and being operative to provide an output DC voltage control signal in said triggering circuit proportional to the power required to maintain thE preset speed under variable load conditions.
Claim 4
Dependent Claim
141 words
Speed control means for an electric motor having a stator field winding and a power delivery rotor with a winding in magnetically coupled relation with the stator field winding, comprising: a. gating means connected in circuit with said rotor winding, and being selectively operable to connect said rotor winding so as to be short-circuited and open-circuited, said gating means including a gate control triggering circuit; and b. means for controlling said triggering circuit comprising a DC reference voltage adjustable to preset the motor speed to a desired value, a DC voltage analog of the motor speed, and a differential lead-lag network having inputs connected to said reference voltage and said analog voltage and being operative to provide an output DC voltage control signal in said triggering circuit proportional to the power required to maintain thE preset speed under variable load conditions.
Claim 5
Dependent Claim
89 words
Control means according to claim 5 including comparator circuits each having one input connected to receive the output of one of the integrator circuits, and another input connected with the output of the differential lead-lag network whereby, when the input from the differential lead-lag circuit for the power required to maintain the preset speed during each cycle and the input from the associated integrator for the remaining power available in the same cycle are equal, the comparator output will actuate the connected triggering circuit to deliver the power required.
Claim 6
Dependent Claim
49 words
Control means according to claim 3, including reset circuit means for controlling the operation of the integrator circuits and the comparator circuits during each cycle in each of the three phases so as to maintain a constant preset speed irrespective of fluctuations of load, voltage, temperature or power factor.
Claim 7
Dependent Claim
170 words
Speed control means for an electric motor having a stator field winding and a power delivery rotor with a winding in magnetically coupled relation with the stator field winding, comprising: a. gating means connected in circuit with said rotor winding, and being selectively operable to connect said rotor winding so as to be short-circuited and open-circuited, said gating means including a gate control triggering circuit; b. means for controlling said triggering circuit comprising a DC reference voltage adjustable to preset the motor speed to a desired value and a DC voltage analog of the motor speed, and which are connected as inputs to a differential lead-lag network to provide an output DC voltage control signal proportional to the power required to maintain the preset speed under variable load conditions; and c. integrator circuits respectively having an input connected with one phase of the rotor circuit and an output signal that is proportional to the remaining power available in each cycle of the connected phase, regardless of the voltage or frequency.
Claim 8
Dependent Claim
170 words
Speed control means for an electric motor having a stator field winding and a power delivery rotor with a winding in magnetically coupled relation with the stator field winding, comprising: a. gating means connected in circuit with said rotor winding, and being selectively operable to connect said rotor winding so as to be short-circuited and open-circuited, said gating means including a gate control triggering circuit; b. means for controlling said triggering circuit comprising a DC reference voltage adjustable to preset the motor speed to a desired value and a DC voltage analog of the motor speed, and which are connected as inputs to a differential lead-lag network to provide an output DC voltage control signal proportional to the power required to maintain the preset speed under variable load conditions; and c. integrator circuits respectively having an input connected with one phase of the rotor circuit and an output signal that is proportional to the remaining power available in each cycle of the connected phase, regardless of the voltage or frequency.
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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) | 1975-04-18 | 1975-10-18 | 1976-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-18 | 1979-10-18 | 1980-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-18 | 1983-10-18 | 1984-04-18 | $7700.00 | Window Closed / Lapsed |