US6756757B2
Expired / Lapsed
US
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Control system and method for a rotating electromagnetic machine
Assignee: Emerson Electric Co
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Filing: 2002-05-21
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Granted: 2004-06-29
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Expires: 2022-05-21
Abstract
Abstract A system and method for controlling a rotating electromagnetic machine. The rotating machine, such as a permanent magnet motor or switched reluctance motor, includes a stator having a plurality of phase windings and a rotor that rotates relative to the stator. A drive is connected to the phase windings for energizing the windings. The control system includes an estimator connectable to the machine for receiving signals representing the phase winding voltage and rotor position. The estimator outputs parameter estimations for an electrical model of the machine based on the received voltage and rotor position. A torque model receives the parameter estimations from the estimator to estimate torque for associated rotor position-phase current combinations of the machine. A controller outputs a control signal to the drive in response to a torque demand and rotor position signals and the torque model. In certain embodiments, a solver uses the torque model to generate energization current profiles according to desired machine behavior, such as smooth torque and/or minimal sensitivity to errors in rotor position measurement.
Inventors
- 👤 Joseph G. Marcinkiewicz
- 👤 Michael I. Henderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:44
CPC Classifications
H; H02; H02P; H02P23/00; H02P23/14; H02P21/00; H02P21/14; H02P21/20; H02P6/00; H02P6/10
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
114 words
A method for controlling a rotating electromagnetic machine, the machine including a stator and a rotor that rotates relative to the stator, the stator including a plurality of phase windings, the method comprising: receiving feedback regarding the rotor position relative to the stator; receiving feedback regarding energization of the phase windings; developing a first mathematical model based on the rotor position and energization feedback to describe electrical behavior of the machine; developing a second mathematical model via a mathematical transform of the first mathematical model to describe torque characteristics of the machine; receiving a torque demand signal; and calculating a phase energization current value via the second mathematical model and the torque demand signal.
Claim 2
Independent Claim
114 words
A method for controlling a rotating electromagnetic machine, the machine including a stator and a rotor that rotates relative to the stator, the stator including a plurality of phase windings, the method comprising: receiving feedback regarding the rotor position relative to the stator; receiving feedback regarding energization of the phase windings; developing a first mathematical model based on the rotor position and energization feedback to describe electrical behavior of the machine; developing a second mathematical model via a mathematical transform of the first mathematical model to describe torque characteristics of the machine; receiving a torque demand signal; and calculating a phase energization current value via the second mathematical model and the torque demand signal.
Claim 3
Dependent Claim
19 words
The method of claim 1 , further comprising energizing the phase windings with the calculated phase energization current value.
Claim 4
Dependent Claim
16 words
The method of claim 2 , wherein the phase windings are energized with a balanced feed.
Claim 5
Dependent Claim
13 words
The method of claim 1 , wherein the first mathematical model is non-linear.
Claim 6
Dependent Claim
30 words
The method of claim 3 , wherein the electrical behavior described by the first mathematical model includes the relationship between voltage, current and rotor position over the predetermined operating range.
Claim 7
Dependent Claim
22 words
The method of claim 1 , wherein the first mathematical model describes electrical behavior of the machine over a predetermined operating range.
Claim 8
Dependent Claim
23 words
The method of claim 1 , wherein the first and second mathematical models include components that comprise products of polynomials and trigonometric functions.
Claim 9
Dependent Claim
19 words
The method of claim 1 , wherein the first and second mathematical models include components that comprise orthogonal functions.
Claim 10
Dependent Claim
15 words
The method of claim 1 , wherein the first mathematical model includes parameters estimated recursively.
Claim 11
Dependent Claim
20 words
The method of claim 8 , wherein collected data older than a predetermined age is not used in parameter estimation.
Claim 12
Dependent Claim
22 words
The method of claim 1 , further comprising generating a lookup table correlating torque demand values with the phase energization current values.
Claim 13
Dependent Claim
27 words
The method of claim 1 , wherein calculating the phase energization current value includes calculating the phase energization current value in accordance with a desired machine behavior.
Claim 14
Dependent Claim
15 words
The method of claim 12 , wherein the desired machine behavior includes minimizing torque ripple.
Claim 15
Dependent Claim
22 words
The method of claim 13 , wherein the phase energization current is further calculated to reduce sensitivity to rotor position measurement errors.
Claim 16
Dependent Claim
15 words
The method of claim 1 further comprising updating the second mathematical model aft predetermined times.
Claim 17
Dependent Claim
17 words
The method of claim 15 , wherein the predetermined times occur when the machine is not operating.
Claim 18
Dependent Claim
19 words
The method of claim 1 , wherein developing the second mathematical model includes modeling the non-load dependent cogging torque.
Claim 19
Dependent Claim
107 words
The method of claim 17 , wherein modeling the non-load dependent cogging torque comprises: spinning the rotor unloaded at a predetermined angular velocity; measuring the phase windings voltage and current: determining the rotor positions associated with the voltage and current measurements; developing a first mathematical model based on the measured voltage and rotor position to describe electrical behavior of the machine; developing a second mathematical model via a mathematical transform of the first mathematical model to describe torque characteristics of the machine; energizing the windings such that the rotor holds a predetermined position; and calculating the cogging torque for the predetermined position via the second mathematical model.
Claim 20
Independent Claim
143 words
A system for controlling a rotating electromagnetic machine including a stator having a plurality of phase windings, a rotor that rotates relative to the stator, and a drive connected to the phase windings for energizing the windings, the control system comprising: an estimator connectable so the machine for receiving signals representing the phase winding voltage and rotor position; the estimator outputting parameter estimations for an electrical model of the machine based on the received voltage and rotor position; a torque model receiving the parameter estimations from the estimator, the torque model outputting estimates of torque for associated rotor position-phase current combinations; and a controller having input terminals for receiving a torque demand signal and the rotor position signal, the controller adapted to output a control signal to the drive in response to the torque demand and rotor position signals and the torque model.
Claim 21
Independent Claim
143 words
A system for controlling a rotating electromagnetic machine including a stator having a plurality of phase windings, a rotor that rotates relative to the stator, and a drive connected to the phase windings for energizing the windings, the control system comprising: an estimator connectable so the machine for receiving signals representing the phase winding voltage and rotor position; the estimator outputting parameter estimations for an electrical model of the machine based on the received voltage and rotor position; a torque model receiving the parameter estimations from the estimator, the torque model outputting estimates of torque for associated rotor position-phase current combinations; and a controller having input terminals for receiving a torque demand signal and the rotor position signal, the controller adapted to output a control signal to the drive in response to the torque demand and rotor position signals and the torque model.
Claim 22
Dependent Claim
16 words
The system of claim 19 , wherein the estimator outputs the model parameters at predetermined times.
Claim 23
Dependent Claim
19 words
The system of claim 20 , wherein the predetermined times comprise times when the rotating machine is not operational.
Claim 24
Dependent Claim
34 words
The system of claim 19 , further comprising a solver coupled to the torque model and the controller, the solver calculating phase current profiles to energize the machine to achieve a predetermined machine behavior.
Claim 25
Dependent Claim
15 words
The system of claim 22 , wherein the predetermined machine behavior includes minimizing torque ripple.
Claim 26
Dependent Claim
22 words
The system of claim 23 , wherein the phase energization current is further calculated to reduce sensitivity to rotor position measurement errors.
Claim 27
Dependent Claim
24 words
The system of claim 22 , wherein the current profiles calculated by the solver are stored in a lookup table accessible by the controller.
Claim 28
Dependent Claim
16 words
The system of claim 22 , wherein the solver updates the current profiles at predetermined times.
Claim 29
Dependent Claim
162 words
A rotating electromagnetic machine system, comprising: a stator; a plurality of phase windings situated in the stator, a rotor situated so as to rotate relative to the stator, a rotor position sensor outputting a signal representing the rotor position relative to the stator, a drive connected to the phase windings for energizing the windings; an estimator connected to the phase windings and the rotor position sensor to receive signals representing the phase winding voltage and rotor position, the estimator outputting parameter estimations for an electrical model of the machine based on the received voltage and rotor position; a torque model receiving the parameter estimations from the estimator, the torque model outputting estimates of torque for associated rotor position-phase current combinations; and a controller having input terminals for receiving a torque demand signal and the rotor position signal, the controller adapted to output a control signal to the drive in response to the torque demand and rotor position signals and the torque model.
Claim 30
Dependent Claim
162 words
A rotating electromagnetic machine system, comprising: a stator; a plurality of phase windings situated in the stator, a rotor situated so as to rotate relative to the stator, a rotor position sensor outputting a signal representing the rotor position relative to the stator, a drive connected to the phase windings for energizing the windings; an estimator connected to the phase windings and the rotor position sensor to receive signals representing the phase winding voltage and rotor position, the estimator outputting parameter estimations for an electrical model of the machine based on the received voltage and rotor position; a torque model receiving the parameter estimations from the estimator, the torque model outputting estimates of torque for associated rotor position-phase current combinations; and a controller having input terminals for receiving a torque demand signal and the rotor position signal, the controller adapted to output a control signal to the drive in response to the torque demand and rotor position signals and the torque model.
Claim 31
Dependent Claim
35 words
The system of claim 27 , further comprising a solver coupled to the torque model and the controller the solver calculating phase current profiles to energize the phase windings to achieve a predetermined machine behavior.
Claim 32
Dependent Claim
24 words
The system of claim 28 , wherein the current profiles calculated by the solver me stored in a lookup table accessible by the controller.
Claim 33
Dependent Claim
17 words
The system of claim 27 , wherein the driver energizes the phase winding: with a balanced feed.
Claim 34
Independent Claim
140 words
A method of determining a non-load dependent cogging torque in a permanent magnet motor having a stator, a plurality of stator windings having terminals connectable to a source of power for energizing the windings, a rotor situated to rotate relative to the stator, the method comprising: spinning the rotor unloaded at a predetermined angular velocity; measuring voltage and current at the motor terminals; determining the rotor positions associated with the voltage and currant measurements; developing a first mathematical model based on the measured voltage and rotor position to describe electrical behavior of the machine; developing a second mathematical model via a mathematical transform of the first mathematical model to describe torque characteristics of the machine; energizing the windings such that the rotor holds a predetermined position; and calculating the cogging torque for the predetermined position via the second mathematical model.
Claim 35
Independent Claim
140 words
A method of determining a non-load dependent cogging torque in a permanent magnet motor having a stator, a plurality of stator windings having terminals connectable to a source of power for energizing the windings, a rotor situated to rotate relative to the stator, the method comprising: spinning the rotor unloaded at a predetermined angular velocity; measuring voltage and current at the motor terminals; determining the rotor positions associated with the voltage and currant measurements; developing a first mathematical model based on the measured voltage and rotor position to describe electrical behavior of the machine; developing a second mathematical model via a mathematical transform of the first mathematical model to describe torque characteristics of the machine; energizing the windings such that the rotor holds a predetermined position; and calculating the cogging torque for the predetermined position via the second mathematical model.
Claim 36
Dependent Claim
25 words
The method of claim 31 , further comprising calculating the cogging torque for a plurality of predetermined positions about a complete revolution of the rotor.
Claim 37
Dependent Claim
16 words
The method of claim 31 , wherein spinning the rotor unloaded comprises spinning the rotor unenergized.
Claim 38
Dependent Claim
18 words
The method of claim 31 , wherein the rotor is spun at a plurality of predetermined angular velocities.
Claim 39
Independent Claim
158 words
A system for controlling a rotating electromagnetic machine including a stator having a plurality of phase windings, a rotor that rotates relative to the stator, and a drive connected to the phase windings for energizing the windings the control system comprising: an estimator connectable to the machine for receiving signals representing the phase winding voltage and rotor position; the estimator outputting parameter estimations for an electrical model of the machine based on the received voltage and rotor position at predetermined times, the predetermined times including times when the rotating machine is not operational; a torque model receiving the parameter estimations from the estimator, the torque model outputting estimates of torque the associated rotor position-phase current combinations; and a controller having input terminals for receiving a torque demand signal and the rotor position signal, the controller adapted to output a control signal to the drive in response to the torque demand and rotor position signals and the torque model.
Claim 40
Independent Claim
158 words
A system for controlling a rotating electromagnetic machine including a stator having a plurality of phase windings, a rotor that rotates relative to the stator, and a drive connected to the phase windings for energizing the windings the control system comprising: an estimator connectable to the machine for receiving signals representing the phase winding voltage and rotor position; the estimator outputting parameter estimations for an electrical model of the machine based on the received voltage and rotor position at predetermined times, the predetermined times including times when the rotating machine is not operational; a torque model receiving the parameter estimations from the estimator, the torque model outputting estimates of torque the associated rotor position-phase current combinations; and a controller having input terminals for receiving a torque demand signal and the rotor position signal, the controller adapted to output a control signal to the drive in response to the torque demand and rotor position signals and the torque model.
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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) | 2007-06-29 | 2007-12-29 | 2008-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-06-29 | 2011-12-29 | 2012-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-06-29 | 2015-12-29 | 2016-06-29 | $7700.00 | Window Closed / Lapsed |