US6498449B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low ripple torque control of a permanent magnet motor without using current sensors
Assignee: GM Global Technology Operations LLC
•
Filing: 2000-09-18
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Granted: 2002-12-24
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Expires: 2020-09-18
Abstract
Abstract A method and apparatus for controlling the torque of and reducing torque ripple in a permanent magnet motor without using current sensors. By eliminating the need for current sensors, low frequency torque ripple is reduced. A voltage mode control method is implemented to control the motor. In response to the position and speed of the rotor and a torque command signal, a controller develops motor voltage command signals indicative of the voltage required to produce the desired motor torque. A rotor position encoder determines the angular positions of the rotor. From the angular positions of the rotor, a speed measuring circuit determines the speed of the rotor. The position and speed signals are applied to the controller. The controller uses this information and develops the motor voltage command signals indicative of the voltage needed to produce the desired motor torque. An inverter is coupled between a power source and the controller. The circuit applies phase voltages to the motor, in response to the motor voltage command signals, to produce the desired motor torque.
Inventors
- 👤 Shaotang Chen
- 👤 Chandra Sekhar Namuduri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:18
CPC Classifications
H; H02; H02P; H02P6/00; H02P6/10; B; B62; B62D; B62D5/00; B62D5/04; B62D5/0457; B62D5/046; H02P21/00; H02P21/22; H02P6/06; H02P6/08; H02P6/14; H02P6/16; H02P6/17
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
105 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; and applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced.
Claim 2
Independent Claim
105 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; and applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced.
Claim 3
Independent Claim
179 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced.
Claim 4
Independent Claim
179 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced.
Claim 5
Independent Claim
190 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced; and wherein said controller does not employ current or voltage feedback.
Claim 6
Independent Claim
190 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced; and wherein said controller does not employ current or voltage feedback.
Claim 7
Independent Claim
236 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein the determining the amplitudes for the input motor phase voltages comprises calculating the amplitudes according to a control equation comprising: V = 1 R cos δ + ( ω L s ) sin δ ( R 2 + ( ω L s ) 2 3 K e T cmd + K e ω m R ) where V=amplitude of the input voltage of the motor; R=resistance of the motor windings; X s =reactance of motor phase winding; K e =E/ω m which is EMF constant; ω m =speed of the motor; T cmd =torque command signal; and δ=angle between EMF phasor {right arrow over (E)} and voltage phasor {right arrow over (V)}.
Claim 8
Independent Claim
236 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein the determining the amplitudes for the input motor phase voltages comprises calculating the amplitudes according to a control equation comprising: V = 1 R cos δ + ( ω L s ) sin δ ( R 2 + ( ω L s ) 2 3 K e T cmd + K e ω m R ) where V=amplitude of the input voltage of the motor; R=resistance of the motor windings; X s =reactance of motor phase winding; K e =E/ω m which is EMF constant; ω m =speed of the motor; T cmd =torque command signal; and δ=angle between EMF phasor {right arrow over (E)} and voltage phasor {right arrow over (V)}.
Claim 9
Independent Claim
207 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein the determining the amplitudes for the input motor phase voltages comprises calculating the amplitudes according to a control equation comprising: V ref =K 1 T cmd +K 2 ω m where V ref =normalized voltage for generating the pulse width modulation signals to control the inverter; K 1 = 6 R 3 K e V dc ; T cmd =torque command signal; K 2 = 6 K e V dc ; K e =E/ω m which is EMF constant; R=resistance of the motor windings; V dc =the DC supply voltage; and ω m =speed of the motor.
Claim 10
Independent Claim
207 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein the determining the amplitudes for the input motor phase voltages comprises calculating the amplitudes according to a control equation comprising: V ref =K 1 T cmd +K 2 ω m where V ref =normalized voltage for generating the pulse width modulation signals to control the inverter; K 1 = 6 R 3 K e V dc ; T cmd =torque command signal; K 2 = 6 K e V dc ; K e =E/ω m which is EMF constant; R=resistance of the motor windings; V dc =the DC supply voltage; and ω m =speed of the motor.
Claim 11
Dependent Claim
167 words
A power steering assist system comprising: a steering wheel and column; an electric motor comprising a motor controller, said electric motor adapted to impart rotational force to said steering column; a power steering controller adapted to control said electric motor in a manner effective in providing power steering assist to an operator of said steering wheel; and wherein said electric motor controller operates by a method comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein said determining does not employ current or voltage feedback.
Claim 12
Dependent Claim
167 words
A power steering assist system comprising: a steering wheel and column; an electric motor comprising a motor controller, said electric motor adapted to impart rotational force to said steering column; a power steering controller adapted to control said electric motor in a manner effective in providing power steering assist to an operator of said steering wheel; and wherein said electric motor controller operates by a method comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein said determining does not employ current or voltage feedback.
Claim 13
Independent Claim
301 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced; and wherein the controller calculates the amplitudes according to a control equation comprising: V = 1 R cos δ + ( ω L s ) sin δ ( R 2 + ( ω L s ) 2 3 K e T cmd + K e ω m R ) where V=amplitude of the input voltage of the motor; R=resistance of the motor windings; X s =reactance of motor phase winding; K e =E/ω m which is EMF constant; ω m =speed of the motor; T cmd =torque command signal; and δ=angle between EMF phasor {right arrow over (E)} and voltage phasor {right arrow over (V)}.
Claim 14
Independent Claim
301 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced; and wherein the controller calculates the amplitudes according to a control equation comprising: V = 1 R cos δ + ( ω L s ) sin δ ( R 2 + ( ω L s ) 2 3 K e T cmd + K e ω m R ) where V=amplitude of the input voltage of the motor; R=resistance of the motor windings; X s =reactance of motor phase winding; K e =E/ω m which is EMF constant; ω m =speed of the motor; T cmd =torque command signal; and δ=angle between EMF phasor {right arrow over (E)} and voltage phasor {right arrow over (V)}.
Claim 15
Independent Claim
273 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced; and wherein the controller calculates the amplitudes according to a control equation comprising: V ref =K 1 T cmd +K 2 ω m where V ref =normalized voltage for generating the pulse width modulation signals to control the inverter; K 1 = 6 R 3 K e V dc ; T cmd =torque command signal; K 2 = 6 K e V dc ; K e =E/ω m which is EMF constant; R=resistance of the motor windings; V dc =the DC supply voltage; and ω m =speed of the motor.
Claim 16
Independent Claim
273 words
An apparatus for controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced; and wherein the controller calculates the amplitudes according to a control equation comprising: V ref =K 1 T cmd +K 2 ω m where V ref =normalized voltage for generating the pulse width modulation signals to control the inverter; K 1 = 6 R 3 K e V dc ; T cmd =torque command signal; K 2 = 6 K e V dc ; K e =E/ω m which is EMF constant; R=resistance of the motor windings; V dc =the DC supply voltage; and ω m =speed of the motor.
Claim 17
Dependent Claim
238 words
A power steering assist apparatus comprising: a steering wheel and column; an electric motor comprising a motor controller, said electric motor adapted to impart rotational force to said steering column; a power steering controller adapted to control said electric motor in a manner effective in providing power steering assist to an operator of said steering wheel; and wherein said motor controller further comprises: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor and wherein said controller does not employ current or voltage feedback; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced.
Claim 18
Dependent Claim
238 words
A power steering assist apparatus comprising: a steering wheel and column; an electric motor comprising a motor controller, said electric motor adapted to impart rotational force to said steering column; a power steering controller adapted to control said electric motor in a manner effective in providing power steering assist to an operator of said steering wheel; and wherein said motor controller further comprises: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor and wherein said controller does not employ current or voltage feedback; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced.
Claim 19
Independent Claim
114 words
A method for reducing torque ripple in a sinusoidally excited permanent magnet motor, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein said determining does not employ current or voltage feedback.
Claim 20
Independent Claim
114 words
A method for reducing torque ripple in a sinusoidally excited permanent magnet motor, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein said determining does not employ current or voltage feedback.
Claim 21
Independent Claim
193 words
An apparatus for reducing torque ripple in a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor, and wherein said controller does not employ current or voltage feedback; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced.
Claim 22
Independent Claim
193 words
An apparatus for reducing torque ripple in a sinusoidally excited permanent magnet motor having known motor parameters, comprising: a position encoder associated with the motor for sensing an angular position of the motor and providing a motor angular position signal indicative thereof; a speed measurement circuit associated with the position encoder for measuring a speed of the motor and providing a motor speed signal indicative thereof; a controller in communication with the position encoder for receiving the motor angular position signal and in communication with the speed measurement circuit for receiving the motor speed signal, the controller providing, in response to the known motor parameters, the motor angular position signal, the motor speed signal, and a torque command signal, voltage command signals, the torque command signal being indicative of a desired torque on the motor, and wherein said controller does not employ current or voltage feedback; and an inverter in communication with the controller for receiving the voltage command signals and in communication with a power source, the inverter applying, in response to the voltage command signals, input motor phase voltages to the motor, wherein the desired torque on the motor is produced.
Claim 23
Independent Claim
115 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein said determining does not employ current or voltage feedback.
Claim 24
Independent Claim
115 words
A method of controlling a sinusoidally excited permanent magnet motor having known motor parameters, comprising: generating a motor angular position signal indicative of an angular position of the motor; generating a motor speed signal indicative of a speed of the motor; determining, in response to the known motor parameters, the motor angular position signal, the motor speed signal, a torque command signal, and amplitudes for input motor phase voltages, the torque command signal being indicative of a desired torque on the motor; applying the input motor phase voltages at the amplitudes determined to the motor, wherein the desired torque on the motor is produced; and wherein said determining does not employ current or voltage feedback.
Claim 25
Dependent Claim
37 words
The method of claim 2 wherein the determining further comprises determining phases of the input motor phase voltages so that the phases of the input motor phase voltages are in phase with respective back-emfs of the motor.
Claim 26
Dependent Claim
19 words
The method of claim 13 wherein the determining phases of the input motor phase voltages utilizes pulse width modulation.
Claim 27
Dependent Claim
18 words
The apparatus of claim 3 wherein the voltage command signals control amplitudes of the input motor phase voltages.
Claim 28
Dependent Claim
37 words
The apparatus of claim 3 wherein the voltage command signals control phases of the input motor phase voltages so that the phases of the input motor phase voltages are in phase with respective back-emfs of the motor.
Claim 29
Dependent Claim
44 words
The apparatus of claim 3 wherein the controller further includes a pulse width modulation circuit for controlling the phases of the input motor phase voltages so that the phases of the input motor phase voltages are in phase with respective back-emfs of the motor.
Claim 30
Dependent Claim
11 words
The apparatus of claim 3 wherein the controller comprises a microprocessor.
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