CA2171107C - Pulse width modulating motor controller - Google Patents

Pulse width modulating motor controller Download PDF

Info

Publication number
CA2171107C
CA2171107C CA002171107A CA2171107A CA2171107C CA 2171107 C CA2171107 C CA 2171107C CA 002171107 A CA002171107 A CA 002171107A CA 2171107 A CA2171107 A CA 2171107A CA 2171107 C CA2171107 C CA 2171107C
Authority
CA
Canada
Prior art keywords
power
motor
signal
power phase
rotor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CA002171107A
Other languages
French (fr)
Other versions
CA2171107A1 (en
Inventor
William A. Harris
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Honeywell Inc
Original Assignee
Honeywell Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Honeywell Inc filed Critical Honeywell Inc
Publication of CA2171107A1 publication Critical patent/CA2171107A1/en
Application granted granted Critical
Publication of CA2171107C publication Critical patent/CA2171107C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P6/00Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
    • H02P6/08Arrangements for controlling the speed or torque of a single motor
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02PCONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P25/00Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/08Reluctance motors

Abstract

A pulse width modulation controller for a variable speed variable torque electric motor. Inputs to the controller are a desired RPM
signal, a motor electrical signal which is a function of the RPM of the rotor of the motor and its angular position relative to the stator, and a torque feed back signal derived from the power phase winding circuits of the motor. The controller produces pulse width modulated power drive signals which are applied to power switches of the power phase winding circuits of the motor to allow electric current to flow through the power phase winding circuits when power phase enables signals produced by the controller sequentially enabling the power switch of a power phase winding circuit to do so. The duty cycle of the power drive signals is a function of the difference between the desired and actual RPM of the motor and the torque of the motor. The frequency of the power drive signals is a fixed integral multiple of the frequency of the power phase enable signals over the full operating range of RPMs of the motor.

Description

PULSE WIDTH MODULATING MOTOR CONTROLLER
( 1 ) Field of the Invention This invention is in the field of motor controllers for variable speed and variable ~ 5 torque electric motors, such as switched reluctance, or SR, motors and permanent magnet, or PM motors, but is not limited to such motors; and more particularly relates to improvements in controlling the pulse width modulation (PWM) of the power drive signals that determine the speed and torque of variable speed electric motors.
(2) Description of Related Art ' Recent developments in power semiconductor devices such as power MOSFETs and insulated gate thyristors (IGT)s have led to the development of electronically commutated motors for use in applications requiring variable speed drive motors.
Conunon examples of the types of electric motors the speed and torque of which are controlled by controllers which pulse width modulate the current flow through the power phase winding circuits of such motors, are SR motors and PM motors; however, the controller of this invention can be used with any electric motor that can be controlled by pulse width modulating the flow of electrical current through the motor's power phase windings. The cost and reliability of the pulse width modulation (PWM) controllers for electric motors compare favorably with those of more conventional controllers for variable speed motors.
Motors such as SR motors and PM motors conventionally have multiple poles on both the stator and rotor. In a SR motor, there are power phase windings on the stator poles, but no windings or permanent magnets on the rotor. Each pole of each pair of diametrically opposite stator poles of a SR motor have series connected windings that form an independent power phase winding. In a PM motor, permanent magnets are usually mounted on the rotor.
Torque to rotate the rotor is produced by switching current into each of the power phase windings in a predetermined sequence that is synchronized with the angular position of the rotor, to polarize an associated pair of stator poles. While generally the power phase windings are placed on poles of the stator, they can be placed on poles of the rotor if so desired. The resulting magnetic force attracts the nearest pair of rotor poles. In a SR
motor, current is switched off in each power, or stator, phase winding before the poles of the rotor nearest the excited stator poles rotate past the aligned position.
In such motors, the torque developed, while a function of the magnitude of the current flow in the stator windings, is independent of the direction of current flow so that unidirectional current pulses synchronized with the rotation of the rotor can be applied to the stator power phase windings by a converter using unidirectional current switching elements such as thyristors or power transistors. The desired commutation of current through the stator phase windings can be accomplished by producing a rotor position signal by means of a shaft position sensor; i.e., an encoder, or resolver, for example, which is driven by the motor's rotor. The rotor position signal is applied to the motor controller.
The motor controller also typically has applied to it a signal indicating the desired direction of rotation of the rotor and a speed set signal indicating the desired angular velocity of the rotor which is typically measured in revolutions per minute (RPM). Such speed and direction signals are controlled by a human operator, or an automated control system. In addition, a rotor position signal, which is also known as the motor electrical (Me) signal; and a torque, or current, feedback signals are also applied to the motor controller. Current for each of the power phase windings of a SR motor is derived from a unidirectional power source, and each of the power phase windings is connected in series with a power transistor to control the flow of current through its associated power phase winding. The motor controller produces pulse width modulation (PWM) power drive signals which are applied to the power transistors to turn them on and off The timing of such current flows relative to the position of the rotor causes the rotor to rotate, and the order in which the power phase windings are energized determines the direction of rotation of the rotor.
The power drive signals applied to the power transistors in series with power phase windings are pulse width modulated (PWM) to maintain current levels through the power phase windings at a level to cause the rotor to rotate at the desired RPM
while limiting the torque, or current, in the power phase windings to a predetermined maximum. It should "
be noted that the magnitude of the torque of a motor is a function of the magnitude of the current flowing through its power phase winding circuits. The magnitude of this current flow is sensed and used to produce a current, or torque, feedback signal which is applied to the motor controller. A prior art circuit for pulse «ridth modulating the power drive signal for a SR motor is illustrated in Fig. 9 of U.S. Patent 5,196,775.
A problem with prior art PWM motor controllers is that there is no fixed relationship between the frequency of the PWM power drive signals and the motor electrical, Me, or power phase commutation signals which results in a beat frequency (PWM-Me) that causes fluctuations at this beat frequency in the speed and torque of the motor. Such fluctuations in and of themselves are undesirable, and in addition they also increase the noise produced by a motor in which such fluctuations occur.
SUMMARY OF THE INVENTION
The present invention provides a pulse width modulation controller for a variable speed variable torque electric motor in which the motor controller produces PWM
power drive signals the frequency of which is a fixed integral multiple "n" of the frequency of the power phase commutation, or power phase enable, signals. These power phase enable signals determine the time period each power phase winding can be energized and the order, or sequence, in which they are energized which determines the direction of rotation of the rotor.
This invention provides a PWM controller for a variable speed and variable torque motor that produces PWM
power drive signals, the frequency of which is a fixed integral multiple of the frequency of the power phase enable signals also produced by the controller.
This invention discloses a PWM controller for an electric motor in which the frequency of the PWM power drive signal is a fixed integral multiple of the power phase enable signal over the complete operating ranges for the RPM
and the torque of the motor.

-3a-Further, this invention teaches a controller which reduces noise and variations in the speed and torque in a variable speed variable torque electric motor by maintaining constant the number of pulses of the PWM power drive signals controlling the flow of electrical current through each power phase winding circuit of a motor during the period of time that each power phase winding circuit can be energized.
In accordance with this invention, there is provided a pulse width modulation controller for an electric motor having a rotor, a stator, and a plurality of power phase (winding) circuits with each power phase circuit including a power switch, and means for producing a motor electrical (Me) signal which is a function of the revolutions per minute (RPM) of the rotor of the motor and its position relative to the stator of the motor;
comprising: circuit means responsive to the Me signal produced by the motor for producing a pulse width modulation signal; circuit means for producing power phase commutation signals the frequency of which has a fixed relationship to the frequency of said pulse width modulation signal, one power phase enable signal for each power phase winding circuit of the motor; circuit means for producing a speed error signal, said speed error signal being a function of the difference between the actual RPM of the rotor and a desired RPM; and pulse width modulation (PWM) circuit means for producing power drive signals for application to the power switch of each of the power phase winding circuits when each power switch is enabled by a power phase enable signal to receive said power drive signals, the frequency of the power drive signals produced by said PWM circuit means being that of the pulse width modulation signal, and the duty cycle of the power drive signals being a function of the speed error signal and of a power phase feedback signal -3b-produced by a power phase winding circuit when a power drive signal is applied to the power switch to energize said circuit, said power phase winding circuits being energized in sequence.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features and advantages of the invention will be readily apparent from the following description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be affected without departing from the spirit and scope of the novel concepts of the disclosure, and in which:
Fig. 1 is a schematic diagram of a prior art SR motor illustrating a conventional motor controller energizing a single stator phase winding of the motor;
Fig. 2 is a schematic cross section through a prior art PM motor.
Fig. 3 is schematic block diagram of a motor controller incorporating the invention for a SR motor;
Fig. 4 is a block diagram of the motor controller of Fig. 3;
Fig. 5 is a block diagram of the PWM current control and power switch logic circuit of Fig. 4; and Fig. 6 is a timing diagram showing the relationship between pulses of the power phase enable signals and pulses of the PWM power drive signals.
~RSC:RTPTTON OF THE INVENTION
For convenience, the operation of the pulse width modulation controller of this invention is described in conjunction with a switched reluctance motor. As pointed out above, the controller of this invention can be used with any type electric motor in which the speed and torque produced by the motor is controlled by pulse width modulation of the power flow through the power phase winding circuits of the motor such as a permanent magnet motor. Referring to Fig. 1, prior art SR motor 10 has a rotor 12 which has no windings, permanent magnets, or commutator. Stator 14 has a relatively small number of stator power phase windings 16 with only one such winding, 16A which includes a pair of series connected coils 18A1 and 18A2 being illustrated in Fig. 1. Rotor 12 is mounted on shaft 20 for rotation around an axis of rotation which coincides with the longitudinal axis of cylindrical sha$ 20. Rotor 12 is preferably made from a plurality of laminations formed, or stamped, from sheets of a magnetically permeable steel alloy.
Stator 14 likewise is preferably formed from a plurality of laminations made of a magnetically permeable steel alloy.
Stator 14, as illustrated in Fig. 1, has eight stator poles 22 and rotor 12 has six rotor poles 24. Coils 18 on diametrically opposite stator poles 22 are connected in series to form four power phase windings 16A, 16B, 16C, and 16D. For ease of illustration, phase windings 16B, 16C, and 16D are not shown in Fig. 1; instead, the stator poles associated with these phase windings are labeled "B", "C", and "D". In a SR motor, different combinations of numbers of stator and rotor poles may be used; for example, a six stator pole and a four rotor pole combination would constitute a three phase motor since it would k ; ~ y PCT/US94/10463 have three stator power phase windings; and an eight stator pole and a six rotor pole motor would constitute a four phase motor since it would have four stator power phase windings.
It should be noted that the number of stator and rotor poles is always an even number.
When a direct current flows through stator power phase winding 16A, both the stator 14 and the rotor 12 are magnetized. This produces a torque causing the rotor 12 to align a pair of its diametrically opposite poles 24 with the excited, or magnetized, stator poles 22A1 and 22A2. The polarity of the torque does not depend on the polarity of the current since the rotor 12 is always attracted to the stator 14 and rotates to an orientation that provides a minimum reluctance path between energized poles. Thus, a SR
motor requires only unipolar current through its power phase windings from power source 26.
Sequential excitation of the phase windings 16A-16D causes rotor 12 to rotate by synchronously aligning a pair of rotor poles 24 with the stator poles 22 whose power phase winding 16 are energized, or excited. While the power phase windings are typically sequentially energized with one phase being turned off concurrent with the next phase being turned on, the energization of the power phase windings may overlap with the succeeding phase being energized before the preceding phase is deenergized.
Rotor position sensor 28 provides controller 30 with information as to the position of rotor 12 relative to stator 14 necessary for synchronization of the rotation of rotor 12 and the sequential excitation, or energization, of stator power phase windings 16A-16D.
In Fig. l, only a basic electrical circuit for energizing stator power phase winding, or phase, 16A is illustrated. Similar circuitry is provided for phases 16B-16D, but are not illustrated. When switch pair 32 are closed, an electrical current builds up in phase 16A
from DC power source 26. When switch pair 32 are opened, the current transfers to diodes 34 which quickly remove and recover any stored energy as the result of energizing phase 16A.
Rotor 12 rotates in the opposite direction to the sequence in which stator phase windings 16A-16D are energized, or excited. Current pulses through phase windings 16A-16D are controlled by controller 30 in response to motor electrical (Me) timing signals produced by rotor position sensor 28 and are timed to occur at specific angles "q"
of rotor 12. Thus, the commutation of the current through stator phase windings 16A-16D
occur at specific rotor angles q with the object being to produce a relatively smooth rotational transition of a rotor pole 24 past an attracting stator pole 22. To accomplish this, Po .
WO 95108214 ~~ ~' ~ PCT/L1S94110463 each power phase winding is substantially deenergized before the attracting stator poles and the attracted rotor poles align.
The timing of when energizing current pulses flow through a stator power phase winding and the duration of such a period, is determined by controller 30 which produces power phase commutation, or power phase enable, signals which are a function of the rotor angle q and the RPM of the motor. The magnitude of the currents in the stator phase windings is controlled by pulse width modulating (PWM) the energizing current flowing through a given power phase winding while that power phase winding is enabled by a power phase enable signal, or pulse.
Referring to Fig. 2, prior art PM motor 36 has a rotor 38 on which are mounted two diametrically opposed permanent magnets 40, 41 with magnets 40 and 41 constituting rotor poles 42, 43. Rotor 3 8 is positioned within stator 44 for rotation with respect to the longitudinal axis of shaft 46 on which rotor 38 is mounted. Stator 44 in the embodiment illustrated in Fig. 2 is provided with two sets of diametrically opposed stator poles 48, 49.
Stator 44 has two stator power phase windings 50, 52 with each of the windings 50, 52 including a pair of series connected coils. Since PM motor 36 has a total of four stator poles, it is a two phase motor.
Other than having permanent magnets mounted on rotor 38, different numbers of stator and rotor poles, and the need to reverse the direction of current flow through the power phase windings 50, 52 each time the current is commutated. For additional information concerning PM motors, reference is made to "D.C. Motors, Speed Control, and Servo Systems; Engineering Handbook; published by Electrocraft Corp.; 3rd.
Edition, 1975.
In Fig. 3, motor 10, its rotor 12, stator, power phase windings, and rotor position sensor are essentially the same as illustrated in Fig. 1. Motor controller 56 has applied to its input terminal 58 a speed set signal, a DC voltage, which is a function of the desired RPM of rotor 12 of motor 10, and to input terminal 60 a direction of rotation signal the polarity of which represents the desired direction of rotation of rotor 12.
Electric current for energizing the coils of each of the power phase windings 16A-16D is derived from power source V+. Each of the power phase windings 16A-16D is connected in series with one of the power switches 62A-D, which are preferably power MOSFETs.
Motor controller 56 produces PWM power drive signals at output terminals 64A-D which are applied respectively to power switches 62A-D. The "on" portion of each pulse of the power drive signal turns on the power switch 62 to which it is applied permitting current to flow through the power phase winding connected in series with the power switch as well as through the one of resistors 66A-D connected in series with each of the power switches 62A-D. Power phase winding 16A, power switch 62A, and resistor 66A
collectively form power phase winding circuit 68A. Similarly power phase windings circuits 68B-D are each made up of a series connected power phase winding, a power switch, and a resistor.
The voltage drop across each of the resistors 66A-D is proportional to the mag~utude of the current flowing through its respective power phase winding circuit 68A-D and provides a measure of the magnitude of the current in any one of the phase windings at any given instant in time. The voltages across resistors 66A-D, constitute a power phase current, or torque feedback, signal, and are applied respectively to input terminals 70A-D of motor controller 56.
Rotor position sensor 28 which can be an encoder, or resolver, for example, produces the motor electrical (Me) signal the timing of the signals of which is a function of the angular position of rotor 12 with respect to stator 14, and the frequency of which is a function of the number of revolutions per minute (RPM) of rotor 12 multiplied by the number of rotor poles 24, six in the preferred example. The Me signal is applied to input terminal 72 of motor controller 56.
In Fig. 4, which is a block diagram in greater detail of motor controller 56, the Me signal applied to input terminal 72 of controller 56 is applied to phase comparator 74 of phase-locked loop, (PLL) 76. The output of voltage controlled oscillator, VCO, 78 of PLL
76 is the pulse width modulation, PWM, signal used in generating pulse width modulated power drive signals that are applied to power transistor 62A-D through output terminals 64A-D of controller 56, as will be explained below. The PWM signals are also applied to "= N" counter 80, the output of which is a power phase commutation signal. The output of = N counter 80 is applied as the second input to phase comparator 74 and also to the clock input terminal 82 of up-down counter 84.
The outputs at terminals A-D of up-down counter 84, power phase enable signals, determine the period of time during which each power phase winding of motor 10 can be energized, and the sequence in which they are to be energized. Counter 84, depending on ~ ~.'~ ~.1 ~ '~
the polarity of the signal applied to it through direction of rotation terminal 60 can be sequenced to count up; i.e. A, B, C, D; or to 'eourit down; i.e., D, C, B, A.
The direction of the count determines whether power phase windings 16A-16D are sequenced in a clockwise or counter clockwise direction, which in turn determines the direction of rotation of rotor 12. Thus, the motor direction command signal applied to input terminal 60 of controller 56 and thence to the up/down control terminal of counter 84 determines the direction of rotation of rotor 12 of motor 10.
The speed set signal, the magnitude of which is a function of the desired RPM
of motor 10, is applied to input terminal 58 of controller 56 and to the positive input terminal of operational amplifier (op-amp) 86. The output of source follower 88 of PLL
76 is applied to the negative input terminal of op amp 86. The magnitude of the voltage produced by source follower 88 of PLL 76 is an actual motor speed voltage signal, and is a function of the instantaneous RPM of rotor 12. The output of op-amp 86, a speed error signal, is positive if the RPM of rotor 12 is less than that specified by the speed set signal and negative if greater. The circuit including diode 90, transistor 92, and potentiometer 94 limits the magnitude of positive speed error signals to limit the maximum current in the power phase windings which in turn limits the maximum torque of motor 10. The speed error signal and PWM signals are applied to each of the PWM current control and power switch logic circuits 96A-D. The phase enable signals present at the A-D
output terminals of counter 84 are applied, respectively, to circuits 96A-D as are phase current feedback signals which are applied to input terminals 70A-D.
Referring to Fig. 5, each of the circuits 96A-D includes an op-amp 98A-D, a set-reset flip flop 100A-D, and an AND gate 102A-D. The PWM signals from PLL 76 are applied to the set terminal "S" of each of the flip flops 100A-D. The signal applied to the reset terminal "R" of flip flop 100A is the output of op-amp 98A of circuit 96A. The speed error signal from the circuit including op-amp 86 is applied to the negative input terminals of op-amps 98A-D, and the phase A current feedback signal, for example, is ' applied to the positive input terminal of op amp 98A.
When a pulse of the PWM signal applied to the set terminal S of flip flop 100A
goes positive, the "Q" output of flip flop 100A goes high and remains so until the voltage at its reset terminal R reaches a value that resets flip flop 100A. The time period between when the Q output goes high and flip flop 100A is reset and the Q output goes low is determined by how long it takes for the output of op-amp 98A to reach the magnitude required to reset flip flop 100A. This is determined by the magnitude and polarity of the speed error signal and the magnitude of the Phase A current feedback signal applied to op amp 98A. The greater the magnitude of the phase A current the narrower the positive portion, or duty cycle, of the pulses at the Q output of flip flop 78. If the speed error is negative, the wider the positive portions and the greater the duty cycle of the pulses, and if the speed error is positive, the smaller the duty cycle.
The Q output of flip flop 100a is applied as one input to AND gate 102A. The other input to AND gate 102A is the phase A enable signal available at the A
output terminal of counter 84. The output of AND gate .102A at terminal 64A is the Phase A
power drive signal that is applied to power transistor 62A. The operations of circuits 96B, 96C, and 96D are substantially identical with that of circuit 96A as set forth above. The result of the operation of circuit 96A, for example, is that the duration of the power on portion, or duty cycle, of each pulse of the power drive signal applied to power switch 62A is a function of the speed error signal and the power phase current, or torque, feedback signals from power phase winding circuit 68A.
In Fig. 6, signals S 1, S2, S3, and S4 illustrate the timing of the A, B, C, and D
power phase enable signals produced at the A. B, C, and D output terminals of counter 84.
Thus, when the B power phase enable signal is positive, AND gate 102B in Fig 5 is enabled so that PWM power drive signals present at the "Q" output of flip flop 100B are transmitted to the power transistor 62B of power phase winding circuit 68B.
With respect to signal SS and S6, the horizontal scale has been increased to better illustrate the shape and number of power drive pulses applied to power transistor 62A, for example, during the time period that the phase A enable pulse of S4 is positive, or on, and during which period AND gate 102A is enabled. Wave form SS illustrates the width, or duration, of the power on portion, or duty cycle, of each phase A power drive signal applied to power drive transistor 62A while the phase A enable pulse is positive and in particular when motor 10 is driving a normal load. Wave form S6 illustrates the width of the power on portion of each phase A power drive signal when motor 10 is driving a small load.
It should be noted that the number of power drive signals applied to a power transistor of a stator phase winding during the period each phase winding is enabled by a phase enable signal is a constant integral, five in the illustrated embodiment, at any motor WO 95/08214 , I'CT/US94/10463 speed and at any loading or torque up to a predetermined maximum torque.
Stated another way, the frequency of the power drive signals is a constant integral multiple of the frequency of the power enable, or power phase commutation, signals at any RPM
of the Y
motor. The limitation as to the maximum torque that motor 10 can generate prevents excessively large currents from flowing through the phase windings which could damage the motor.
Obviously many modification and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may be practiced other than as specifically described and illustrated.

Claims (20)

CLAIMS:
1. A pulse width modulation controller for an electric motor having a rotor, a stator, anal a plurality of power phase (winding) circuits with each power phase circuit including a power switch, and means for producing a motor electrical (Me) signal which is a function of the revolutions per minute (RPM) of the rotor of the motor and its position relative to the stator of the motor;
comprising:
circuit means responsive to the Me signal produced by the motor for producing a pulse width modulation signal;
circuit means for producing power phase commutation signals the frequency of which has a fixed relationship to the frequency of said pulse width modulation signal, one power phase enable signal for each power phase winding circuit of the motor;
circuit means for producing a speed error signal, said speed error signal being a function of the difference between the actual RPM of the rotor and a desired RPM; and pulse width modulation (PWM) circuit means for producing power drive signals for application to the power switch of each of the power phase winding circuits when each power switch is enabled by a power phase enable signal to receive said power drive signals, the frequency of the power drive signals produced by said PWM circuit means being that of the pulse width modulation signal, and the duty cycle of the power drive signals being a function of the speed error signal and of a power phase feedback signal produced by a power phase winding circuit when a power drive signal is applied to the power switch to energize said circuit, said power phase winding circuits being energized in sequence.
2. The pulse width modulation controller of claim 1 in which the fixed relationship between the power phase commutation signal and the frequency of the pulse width modulation signal is that the frequency of the power phase commutation signal is equal to 1/n times the frequency of the pulse width modulation signal and "n" is a positive integer.
3. The pulse width modulation controller of claim 2 in which the electric motor is a variable reluctance motor having a rotor with "R" poles where "R" is an even integer and Me frequency equals the RPM of the rotor multiplied by R.
4. The pulse width modulation controller of claim 3 in which each power phase winding includes means for producing a power phase feedback signal.
5. The pulse width modulation controller of claim 1 in which the electric motor is a permanent magnet motor.
6. A pulse width modulation controller for an electric motor having a rotor, a stator, and a plurality of power phase winding circuits with each power phase circuit including a power switch, and means for producing a motor electrical (Me) signal which is a function of the revolutions per minute (RPM) of the rotor of the motor and its position relative to the stator of the motor;
comprising:
circuit means responsive a Me signal produced by the motor for producing a pulse width modulation signal;
circuit means for producing a power phase commutation signal the frequency of which is 1/n times the frequency of said pulse width modulation signal, where "n"
is an integer greater than one;

circuit means to which the said phase commutation signal is applied for producing power phase enable signals, one power phase enable signal for each power phase winding circuit of the motor;
circuit means for producing a speed error signal, said speed error signal being a function of the difference between the actual RPM of the rotor and a desired RPM; and a plurality of pulse width modulation (PWM) circuit means, each of the PWM circuit means being associated with one of the power phase winding circuits of the motor and for producing for its associated power phase winding circuit a power drive signal for application to the power switch of its associated power phase winding circuit when a power phase enable signal is applied to one of said PWM circuit means, the frequency of the power drive signals produce by said PWM circuit means being that of the pulse width modulation signal, and the duty cycle of the power drive signals being a function of the speed error signal and of a power phase feedback signal produced by each power phase winding circuit when a power drive signal is applied to the power switch of a power phase winding circuit to energize said circuit, said power phase winding circuit being energized in sequence to cause the rotor of the motor to rotate.
7. The pulse width modulation controller for a variable speed variable torque electric motor of claim 6 in which the rotor of the motor has "R" poles and the stator has "S" poles, where "R" and "S" are even integers, and the power phase winding circuits are positioned on the stator poles.
8. The pulse width modulation controller for a variable speed variable torque electric motor of claim 7 in which the electric motor is a variable reluctance motor and the frequency of Me equals the RPM of the rotor multiplied by R.
9. The pulse width modulation controller for a variable speed variable torque electric motor of claim 8 in which the integer "n" equals 5.
10. The pulse width modulation controller for a variable speed variable torque electric motor of claim 8 in which the electric motor is a permanent magnet motor.
11. A pulse width modulation motor controller for a variable speed and variable torque electric motor including a stator having a first set of "S" diametrically opposed stator poles, a rotor mounted within the stator for rotation about an axis of rotation, said rotor having a second set of "R" diametrically opposed rotor poles, where "S" and "R" are even integers, each pair of diametrically opposed poles of one of the set of poles having a series connected power phase winding, means for producing a pulsed motor electrical (Me) signal the timing of the pulses of which is a function of the angular position of the rotor with respect to the stator, the frequency of which is a function of the revolutions per minute (RPM) of the rotor, and the number of rotor poles; power switch means connected in series with each of the power phase windings for permitting electrical current to flow through a power phase winding in response to a power on portion of a pulse of a power drive signal being applied to the switch means thereof; and circuit means connected to each of the power phase windings for producing a current feedback signal which is a function of the current flowing through any of the power phase windings at any instant in time; said motor controller comprising:

first circuit means to which is applied the Me signal for producing a pulse width modulation (PWM) signal which is in phase with the Me signal, and a second signal that is a function of the RPM of the rotor of the motor;
second circuit means to which is applied the voltage that is a function of the RPM of the rotor produced by the first circuit means, and a speed set voltage which is a function of the desired RPM of the rotor for producing a speed error signal;
third circuit means to which is applied the PWM
signal produced by the first circuit means for a power phase commutation signal, the frequency of which is 1/n times the frequency of the PWM signal applied thereto, where "n" is a positive integer greater than one;
fourth circuit means to which is applied the power phase commutation signal produced by the third circuit means for producing power phase enable signals, one for each power phase winding of the motor; and PWM current control and power switch logic means, one for each power phase winding of the motor to each of which is applied the speed error signal, the PWM signal, and to each of them respectively a power phase enable signal and a power phase current feedback signal, each of the PWM
current control and power switch logic means for producing a pulse width modulated power drive signal having a duty cycle and a frequency the duty cycle of which is a function of the speed error signal and the current feedback signal. and the frequency of which is "n" times the power phase enabling signal for application respectively to the power switch means connected in series with each power phase winding of the motor to control the electrical current flow sequentially through each of the power phase windings to cause the rotor to rotate.
12. The pulse width modulation motor controller of claim 11 in which a series connected power phase winding is placed around each pair of diametrically opposed stator windings.
13. The pulse width modulation motor controller of claim 12 in which "S" is greater than "R".
14. The pulse width modulation motor controller of claim 13 in which the first circuit means is a phase-locked-loop device.
15. The pulse width modulation motor controller of claim 14 in which the fourth circuit means is an up/down counter.
16. The pulse width modulation motor controller of claim 15 in which the electric motor is a variable reluctance motor.
17. The pulse width modulation motor controller of claim 15 in which the electric motor is a permanent magnet motor with permanent magnets positioned on the rotor.
18. A pulse width modulation controller for a switched reluctance motor; said motor having a stator having eight diametrically opposed stator poles; a rotor mounted within the stator for rotation about an axis of rotation, said rotor having six diametrically opposed rotor poles; each pair of diametrically opposed stator poles having a series connected power phase winding forming four stator power phase windings; means for producing a motor electrical (Me) signal the timing of the pulses of which is a function of the angular position of the rotor with respect to the stator, and the frequency of which is a function of the revolutions per minute (RPM) of the rotor multiplied by the number of rotor poles; power switch means connected in series with each of the stator phase windings for controlling flow of electrical current through each power phase winding in response to a power on portion of each pulse of a power drive signal applied to the switch means thereof; and circuit means connected to the stator power phase windings for producing a torque feedback signal which is a function of the current flowing through a stator power phase winding at any instant in time; said controller comprising:
circuit means to which is applied a speed set voltage which is a function of a desired RPM of the rotor of the motor and an actual speed voltage which is a function of the actual RPM of the rotor of the motor for producing a speed error signal;
a divide by "n" counter circuit having an input terminal and an output terminal:
phase-locked-loop (PLL) circuit means including a first signal input terminal to which is applied the Me signal produced by the motor controlled by the controller, a phase comparator input terminal, and a voltage-controlled oscillator (VCO) which produces a pulse width modulation (PWM) signal;
circuit means for applying the PWM signal produced by the VCO to the input terminal of the divide by "n"
counter circuit, the divide by "n" counter circuit producing power phase commutation signals at its output terminal;

circuit means for connecting the output terminal of the divide by "n" counter to the phase comparator input terminal of the PLL;
an up/down counter circuit to which is applied the power phase commutation signals for producing power phase enable signals for each of the power phase windings of the motor;
PWM duty cycle control means to which is applied the speed error signal and the torque feedback signals produced by the motor for varying the duration of the power on portion of each pulse of the PWM signal as a function of the difference between the speed error signal and the torque feedback signals for producing PWM power drive signals, the frequencies of which are the same as the frequency of the PWM signal at the VCO output terminal of the PLL; and logic and power switch control circuit means to which is applied the PWM power drive signals from the PWM
duty cycle control means and the phase enable signal produced by the divide by "n" counter for applying PWM power drive signals to the power circuit means of the motor to energize the phase winding sequentially and in synchronization with the rotation of the rotor.
19. The pulse width modulation controller of claim 18 in which "n" is a positive integer.
20. The pulse width modulation controller of claim 19 in which "n" equals five.
CA002171107A 1993-09-16 1994-09-16 Pulse width modulating motor controller Expired - Fee Related CA2171107C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/122,872 1993-09-16
US08/122,872 US5489831A (en) 1993-09-16 1993-09-16 Pulse width modulating motor controller
PCT/US1994/010463 WO1995008214A1 (en) 1993-09-16 1994-09-16 Pulse width modulating motor controller

Publications (2)

Publication Number Publication Date
CA2171107A1 CA2171107A1 (en) 1995-03-23
CA2171107C true CA2171107C (en) 2003-08-19

Family

ID=22405332

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002171107A Expired - Fee Related CA2171107C (en) 1993-09-16 1994-09-16 Pulse width modulating motor controller

Country Status (7)

Country Link
US (1) US5489831A (en)
EP (1) EP0719473B1 (en)
JP (1) JP3432226B2 (en)
CA (1) CA2171107C (en)
DE (1) DE69410476T2 (en)
TW (1) TW301819B (en)
WO (1) WO1995008214A1 (en)

Families Citing this family (108)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB9311176D0 (en) * 1993-05-29 1993-07-14 Univ Warwick Electric motor drive
JPH09121590A (en) * 1995-09-14 1997-05-06 Copeland Corp Rotary compressor provided with counter-current braking mechanism
GB2305518B (en) * 1995-09-26 1999-11-03 Custom Dev Ltd Electronic actuator position control
DE19781648T1 (en) * 1996-03-15 1999-04-01 Dana Corp System for controlling the operation of a switched reluctance motor between a multi-phase mode and a reduced phase mode
US5861727A (en) * 1996-04-17 1999-01-19 Dana Corporation System for controlling operation of a switched reluctance motor between multi-phase operating mode and a reduced phase operating mode
US6017143A (en) 1996-03-28 2000-01-25 Rosemount Inc. Device in a process system for detecting events
US8290721B2 (en) * 1996-03-28 2012-10-16 Rosemount Inc. Flow measurement diagnostics
US7949495B2 (en) * 1996-03-28 2011-05-24 Rosemount, Inc. Process variable transmitter with diagnostics
US7630861B2 (en) * 1996-03-28 2009-12-08 Rosemount Inc. Dedicated process diagnostic device
US7254518B2 (en) * 1996-03-28 2007-08-07 Rosemount Inc. Pressure transmitter with diagnostics
US6539267B1 (en) 1996-03-28 2003-03-25 Rosemount Inc. Device in a process system for determining statistical parameter
US6654697B1 (en) 1996-03-28 2003-11-25 Rosemount Inc. Flow measurement with diagnostics
US5821715A (en) * 1996-07-26 1998-10-13 Western Digital Corporation Pulsed alignment commutation state for sensorless motor start
US5956663A (en) * 1996-11-07 1999-09-21 Rosemount, Inc. Signal processing technique which separates signal components in a sensor for sensor diagnostics
US6434504B1 (en) 1996-11-07 2002-08-13 Rosemount Inc. Resistance based process control device diagnostics
US5828567A (en) * 1996-11-07 1998-10-27 Rosemount Inc. Diagnostics for resistance based transmitter
US6601005B1 (en) 1996-11-07 2003-07-29 Rosemount Inc. Process device diagnostics using process variable sensor signal
US6754601B1 (en) 1996-11-07 2004-06-22 Rosemount Inc. Diagnostics for resistive elements of process devices
US6449574B1 (en) 1996-11-07 2002-09-10 Micro Motion, Inc. Resistance based process control device diagnostics
US6519546B1 (en) 1996-11-07 2003-02-11 Rosemount Inc. Auto correcting temperature transmitter with resistance based sensor
GB9623865D0 (en) * 1996-11-15 1997-01-08 Switched Reluctance Drives Ltd An electric machine
CN1138193C (en) * 1996-12-31 2004-02-11 罗斯蒙德公司 Device in process system for validating control signal from from field device
JP3425369B2 (en) * 1997-09-24 2003-07-14 東芝テック株式会社 3 phase motor
CA2306767C (en) 1997-10-13 2007-05-01 Rosemount Inc. Communication technique for field devices in industrial processes
FR2778798B1 (en) * 1998-05-15 2000-07-28 Moulinex Sa METHOD FOR CONTROLLING AN ELECTRONICALLY SWITCHED ELECTRIC MOTOR, AND CONTROL CIRCUIT FOR IMPLEMENTING IT
US6198265B1 (en) 1998-06-19 2001-03-06 Unisem, Inc. Fixed frequency switching regulator with improved dynamic response
US6208216B1 (en) * 1998-09-28 2001-03-27 Mikko J. Nasila Phase-locked-loop pulse-width modulation system
US6611775B1 (en) 1998-12-10 2003-08-26 Rosemount Inc. Electrode leakage diagnostics in a magnetic flow meter
US6615149B1 (en) 1998-12-10 2003-09-02 Rosemount Inc. Spectral diagnostics in a magnetic flow meter
US8044793B2 (en) * 2001-03-01 2011-10-25 Fisher-Rosemount Systems, Inc. Integrated device alerts in a process control system
US7562135B2 (en) * 2000-05-23 2009-07-14 Fisher-Rosemount Systems, Inc. Enhanced fieldbus device alerts in a process control system
US6298454B1 (en) 1999-02-22 2001-10-02 Fisher-Rosemount Systems, Inc. Diagnostics in a process control system
US7206646B2 (en) * 1999-02-22 2007-04-17 Fisher-Rosemount Systems, Inc. Method and apparatus for performing a function in a plant using process performance monitoring with process equipment monitoring and control
US6633782B1 (en) 1999-02-22 2003-10-14 Fisher-Rosemount Systems, Inc. Diagnostic expert in a process control system
US6356191B1 (en) 1999-06-17 2002-03-12 Rosemount Inc. Error compensation for a process fluid temperature transmitter
DE19928357A1 (en) * 1999-06-21 2001-01-04 Sig Positec Bergerlahr Gmbh & Operating method for synchronous machine e.g. stepper motor, involves synchronizing switching frequency to integral multiple of control signal fundamental frequency, and tracking it when machine speed varies
US7010459B2 (en) * 1999-06-25 2006-03-07 Rosemount Inc. Process device diagnostics using process variable sensor signal
DE60014709T3 (en) 1999-07-01 2010-04-15 Rosemount Inc., Eden Prairie TWO-WIRE TRANSMITTER WITH SELF-TESTING AND LOW POWER
US6505517B1 (en) 1999-07-23 2003-01-14 Rosemount Inc. High accuracy signal processing for magnetic flowmeter
US6256185B1 (en) 1999-07-30 2001-07-03 Trombetta, Llc Low voltage direct control universal pulse width modulation module
US6701274B1 (en) 1999-08-27 2004-03-02 Rosemount Inc. Prediction of error magnitude in a pressure transmitter
US6556145B1 (en) 1999-09-24 2003-04-29 Rosemount Inc. Two-wire fluid temperature transmitter with thermocouple diagnostics
DE19955247A1 (en) * 1999-11-17 2001-05-31 Bosch Gmbh Robert Method for starting a sensorless and brushless DC motor
US6671459B1 (en) * 2000-06-30 2003-12-30 General Electric Company DC motor control method and apparatus
US6735484B1 (en) 2000-09-20 2004-05-11 Fargo Electronics, Inc. Printer with a process diagnostics system for detecting events
US8073967B2 (en) 2002-04-15 2011-12-06 Fisher-Rosemount Systems, Inc. Web services-based communications for use with process control systems
EP1366398A2 (en) * 2001-03-01 2003-12-03 Fisher-Rosemount Systems, Inc. Automatic work order/parts order generation and tracking
WO2002071173A2 (en) * 2001-03-01 2002-09-12 Fisher-Rosemount Systems, Inc. Data sharing in a process plant
US7720727B2 (en) * 2001-03-01 2010-05-18 Fisher-Rosemount Systems, Inc. Economic calculations in process control system
US6629059B2 (en) 2001-05-14 2003-09-30 Fisher-Rosemount Systems, Inc. Hand held diagnostic and communication device with automatic bus detection
US20020191102A1 (en) * 2001-05-31 2002-12-19 Casio Computer Co., Ltd. Light emitting device, camera with light emitting device, and image pickup method
US6740163B1 (en) * 2001-06-15 2004-05-25 Seagate Technology Llc Photoresist recirculation and viscosity control for dip coating applications
US6772036B2 (en) 2001-08-30 2004-08-03 Fisher-Rosemount Systems, Inc. Control system using process model
KR100439199B1 (en) * 2001-11-29 2004-07-07 (주)지엔더블유테크놀러지 Brushless dc motor having parallel connected windings and control circuit for it
JP3932408B2 (en) * 2002-02-01 2007-06-20 ミネベア株式会社 Brushless DC 1-phase motor pre-drive circuit
US7084597B2 (en) * 2002-06-03 2006-08-01 Denso Corporation Motor control apparatus
US7161314B2 (en) * 2002-10-07 2007-01-09 Denso Corporation Motor control apparatus having current supply phase correction
US6836087B2 (en) * 2003-01-29 2004-12-28 Wavecrest Laboratories, Llc Multiphase motor voltage control for phase windings of different wire gauges and winding turns
JP2004328991A (en) * 2003-04-09 2004-11-18 Nissan Motor Co Ltd Left and right wheel driving device for vehicle
US7290450B2 (en) * 2003-07-18 2007-11-06 Rosemount Inc. Process diagnostics
US7018800B2 (en) * 2003-08-07 2006-03-28 Rosemount Inc. Process device with quiescent current diagnostics
US7627441B2 (en) * 2003-09-30 2009-12-01 Rosemount Inc. Process device with vibration based diagnostics
US6954044B2 (en) * 2003-12-11 2005-10-11 Honeywell International Inc. Electric motor with speed control
US7112907B2 (en) 2003-12-12 2006-09-26 Siemens Vdo Automotive Inc. Flux modifier for a permanent magnet brush-type motor using wound field coils combined with permanent magnets
US7523667B2 (en) * 2003-12-23 2009-04-28 Rosemount Inc. Diagnostics of impulse piping in an industrial process
JP4583111B2 (en) 2004-08-31 2010-11-17 ルネサスエレクトロニクス株式会社 Motor drive control device and disk rotation system
US8005647B2 (en) 2005-04-08 2011-08-23 Rosemount, Inc. Method and apparatus for monitoring and performing corrective measures in a process plant using monitoring data with corrective measures data
US9201420B2 (en) 2005-04-08 2015-12-01 Rosemount, Inc. Method and apparatus for performing a function in a process plant using monitoring data with criticality evaluation data
US8112565B2 (en) * 2005-06-08 2012-02-07 Fisher-Rosemount Systems, Inc. Multi-protocol field device interface with automatic bus detection
US7272531B2 (en) * 2005-09-20 2007-09-18 Fisher-Rosemount Systems, Inc. Aggregation of asset use indices within a process plant
US20070068225A1 (en) * 2005-09-29 2007-03-29 Brown Gregory C Leak detector for process valve
US7953501B2 (en) 2006-09-25 2011-05-31 Fisher-Rosemount Systems, Inc. Industrial process control loop monitor
US8788070B2 (en) * 2006-09-26 2014-07-22 Rosemount Inc. Automatic field device service adviser
US7750642B2 (en) 2006-09-29 2010-07-06 Rosemount Inc. Magnetic flowmeter with verification
TWI334764B (en) * 2006-12-01 2010-12-11 Delta Electronics Inc Fan system and starting method thereof
CN101201059B (en) * 2006-12-12 2011-05-04 台达电子工业股份有限公司 Fan system and starting method therefor
US7598683B1 (en) 2007-07-31 2009-10-06 Lsi Industries, Inc. Control of light intensity using pulses of a fixed duration and frequency
US8903577B2 (en) 2009-10-30 2014-12-02 Lsi Industries, Inc. Traction system for electrically powered vehicles
US8604709B2 (en) 2007-07-31 2013-12-10 Lsi Industries, Inc. Methods and systems for controlling electrical power to DC loads
US8898036B2 (en) * 2007-08-06 2014-11-25 Rosemount Inc. Process variable transmitter with acceleration sensor
US8301676B2 (en) * 2007-08-23 2012-10-30 Fisher-Rosemount Systems, Inc. Field device with capability of calculating digital filter coefficients
US7702401B2 (en) 2007-09-05 2010-04-20 Fisher-Rosemount Systems, Inc. System for preserving and displaying process control data associated with an abnormal situation
US7590511B2 (en) * 2007-09-25 2009-09-15 Rosemount Inc. Field device for digital process control loop diagnostics
US8055479B2 (en) 2007-10-10 2011-11-08 Fisher-Rosemount Systems, Inc. Simplified algorithm for abnormal situation prevention in load following applications including plugged line diagnostics in a dynamic process
JP5165400B2 (en) * 2008-01-23 2013-03-21 オリンパス株式会社 Light source device
WO2010008398A1 (en) * 2008-07-18 2010-01-21 Flowserve Management Company Variable speed actuator
US10094485B2 (en) 2008-07-18 2018-10-09 Flowserve Management Company Variable-speed actuator
US10100827B2 (en) * 2008-07-28 2018-10-16 Eaton Intelligent Power Limited Electronic control for a rotary fluid device
US8596051B2 (en) * 2008-10-17 2013-12-03 Eaton Corporation Control valve actuation
US7921734B2 (en) * 2009-05-12 2011-04-12 Rosemount Inc. System to detect poor process ground connections
DE102009027346A1 (en) * 2009-06-30 2011-01-05 Robert Bosch Gmbh Method and electrical circuit for operating an electric motor, in particular a servomotor for a component of an internal combustion engine
WO2011049980A1 (en) * 2009-10-19 2011-04-28 Qm Power, Inc. Parallel magnetic circuit motor
US9385641B2 (en) * 2009-11-18 2016-07-05 Standard Microsystems Corporation System and method for inducing rotation of a rotor in a sensorless motor
US8896246B2 (en) * 2010-05-28 2014-11-25 Standard Microsystems Corporation Method for aligning and starting a BLDC three phase motor
US9207670B2 (en) 2011-03-21 2015-12-08 Rosemount Inc. Degrading sensor detection implemented within a transmitter
US9927788B2 (en) 2011-05-19 2018-03-27 Fisher-Rosemount Systems, Inc. Software lockout coordination between a process control system and an asset management system
DE102012009856B3 (en) * 2012-05-21 2013-05-29 Brose Fahrzeugteile Gmbh & Co. Kommanditgesellschaft, Hallstadt Drive assembly for adjusting e.g. tailgate of motor car, sets modulation switching frequency associated with motors to be different from each other at specific time, during the adjusting of provided continuously shifting frequency
US9052240B2 (en) 2012-06-29 2015-06-09 Rosemount Inc. Industrial process temperature transmitter with sensor stress diagnostics
US9207129B2 (en) 2012-09-27 2015-12-08 Rosemount Inc. Process variable transmitter with EMF detection and correction
US9602122B2 (en) 2012-09-28 2017-03-21 Rosemount Inc. Process variable measurement noise diagnostic
KR20140086496A (en) * 2012-12-28 2014-07-08 삼성전기주식회사 The method of controlling switch relectance motor and apparatus using the same
CN104201855B (en) * 2014-08-27 2016-08-24 中国矿业大学 A kind of four phase switch reluctance motor torque ripple two level suppressing method
DE102016106547A1 (en) * 2016-04-11 2017-10-12 Robert Bosch Gmbh SWITCHING DEVICE FOR AN ELECTRIC MOTOR, CONTROL DEVICE, STEERING SYSTEM
FR3055759B1 (en) 2016-09-02 2020-10-30 Mmt ag MECHATRONIC ASSEMBLY PILOT BY A PULSE WIDTH MODULATING SIGNAL
FR3081269B1 (en) 2018-05-17 2020-05-22 Sonceboz Automotive Sa MECATRONIC ASSEMBLY FOR DRIVING OR POSITIONING AN EXTERNAL MEMBER
US11499372B2 (en) * 2019-10-28 2022-11-15 Halliburton Energy Services, Inc. Downhole tractor control systems and methods to adjust a load of a downhole motor
TWI771099B (en) * 2021-07-12 2022-07-11 致新科技股份有限公司 Motor controller
US11764709B2 (en) 2021-07-15 2023-09-19 Global Mixed-Mode Technology Inc. Motor controller

Family Cites Families (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3436635A (en) * 1965-09-02 1969-04-01 Bendix Corp Pulse width modulated servo drive control system
US3569805A (en) * 1968-08-28 1971-03-09 Reliance Electric Co Synchronizing circuit
US3560827A (en) * 1969-05-09 1971-02-02 Security Trust Co Of Rochester System for controlling the velocity and position of a rotating member
US3753067A (en) * 1972-05-17 1973-08-14 Peripheral Systems Corp Motor speed regulation system
US4186334A (en) * 1978-02-07 1980-01-29 Tokyo Shibaura Denki Kabushiki Kaisha Control systems of alternating current motors
US4456859A (en) * 1978-04-12 1984-06-26 Janome Sewing Machine Co. Ltd. Sewing machine drive motor control system
DE2833593C2 (en) * 1978-07-31 1980-09-25 Siemens Ag, 1000 Berlin Und 8000 Muenchen Circuit arrangement for generating an electrical voltage signal which is proportional to a flux component in a rotating field machine
JPS5662092A (en) * 1979-10-24 1981-05-27 Hitachi Ltd Controlling system for inverter of induction motor
JPS5671855A (en) * 1979-11-15 1981-06-15 Sony Corp Playback device of disc
US4300081A (en) * 1980-03-14 1981-11-10 General Motors Corporation Motor voltage feedback for a servo motor control system
US4465961A (en) * 1981-06-15 1984-08-14 Zycron Systems, Inc. Motor control system
JPS5854885A (en) * 1981-09-25 1983-03-31 Sony Corp Control circuit for direct current motor
JPS597964A (en) * 1982-07-06 1984-01-17 Canon Inc Recording medium driving device
US4546293A (en) * 1982-08-24 1985-10-08 Sundstrand Corporation Motor control for a brushless DC motor
JPS5981712A (en) * 1982-11-02 1984-05-11 Canon Inc Control system
JPS60167688A (en) * 1984-01-26 1985-08-31 Canon Inc Rotating phase control circuit
DE3573497D1 (en) * 1984-03-08 1989-11-09 Meidensha Electric Mfg Co Ltd DIGITAL PWMED PULSE GENERATOR
JPS60241784A (en) * 1984-05-15 1985-11-30 Sanyo Electric Co Ltd Controller of dc servo motor
US4602201A (en) * 1984-06-05 1986-07-22 Westinghouse Electric Corp. PWM motor drive with torque determination
DE3578867D1 (en) * 1984-10-19 1990-08-30 Kollmorgen Corp VARIABLE RELUCTIVE MACHINE WITH VARIABLE SPEED.
JPS61240875A (en) * 1985-04-16 1986-10-27 Fanuc Ltd Controlling method for 3-phase induction motor
SE457307B (en) * 1986-06-17 1988-12-12 Ems Electronic Motor Systems PROCEDURE AND DEVICE FOR CONTROL OF A BRUSHLESS DC POWER MOTOR
US4734628A (en) * 1986-12-01 1988-03-29 Carrier Corporation Electrically commutated, variable speed compressor control system
US4924168A (en) * 1987-06-01 1990-05-08 Hitachi, Ltd. Control apparatus for PWM-controlled, variable voltage/variable frequency inverters
US4843288A (en) * 1988-03-28 1989-06-27 Rigidyne Corporation Phase locked motor control system for multiple disk drive units
US4897583A (en) * 1989-03-07 1990-01-30 Sundstrand Corporation Variable speed variable torque brushless DC motor
US5072166A (en) * 1990-06-18 1991-12-10 The Texas A&M University System Position sensor elimination technique for the switched reluctance motor drive
US5208740A (en) * 1991-05-30 1993-05-04 The Texas A & M University System Inverse dual converter for high-power applications
KR100234731B1 (en) * 1992-02-21 1999-12-15 구자홍 Position detecting device of a srm

Also Published As

Publication number Publication date
US5489831A (en) 1996-02-06
DE69410476T2 (en) 1998-12-10
EP0719473B1 (en) 1998-05-20
EP0719473A1 (en) 1996-07-03
WO1995008214A1 (en) 1995-03-23
TW301819B (en) 1997-04-01
CA2171107A1 (en) 1995-03-23
JPH09502860A (en) 1997-03-18
JP3432226B2 (en) 2003-08-04
DE69410476D1 (en) 1998-06-25

Similar Documents

Publication Publication Date Title
CA2171107C (en) Pulse width modulating motor controller
US4447771A (en) Control system for synchronous brushless motors
US5245256A (en) Closed loop control of a brushless DC motor at nominal speed
US6586898B2 (en) Systems and methods of electric motor control
EP0123807B1 (en) Driving and detection of back emf in permanent magnet step motors
US4368411A (en) Control system for electric motor
US5001405A (en) Position detection for a brushless DC motor
US4658194A (en) Closed loop control circuitry for step motors
JP4133054B2 (en) Braking control method and circuit for electronic commutator electric motor
US4884016A (en) Closed loop torque angle control of synchronous motor
US6121744A (en) Control apparatus for position control motor
US20070252540A1 (en) Systems for brushless dc electrical drive control
WO1990009700A1 (en) Control arrangement for a reluctance motor
US4746843A (en) Motor control circuit and drive amplifier for a permanent magnet DC torque motor
EP1219013B1 (en) State advance controller commutation loop for brushless d.c. motors
JPH11215894A (en) Stepping motor controller
Kusko et al. Definition of the brushless DC motor
JPH0236788A (en) Method and circuit for control of brushless electric motor
US5150030A (en) Motor driving device
CA2440381C (en) A brushless motor control system
JPS5843200A (en) Exciting system for step motor
US4882523A (en) Direct current motor commutation control
JP3427575B2 (en) DC brushless motor and its stopping method
US5554916A (en) Method of starting a sensorless motor
WO1987002527A2 (en) Device for automatic control of direct current motors

Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed

Effective date: 20130917