WO2002066310A1 - Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple - Google Patents

Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple Download PDF

Info

Publication number
WO2002066310A1
WO2002066310A1 PCT/US2001/005012 US0105012W WO02066310A1 WO 2002066310 A1 WO2002066310 A1 WO 2002066310A1 US 0105012 W US0105012 W US 0105012W WO 02066310 A1 WO02066310 A1 WO 02066310A1
Authority
WO
WIPO (PCT)
Prior art keywords
variable
electric power
torque
assist torque
power steering
Prior art date
Application number
PCT/US2001/005012
Other languages
English (en)
Inventor
Shaotang Chen
David Graber
Original Assignee
Delphi Technologies, 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 Delphi Technologies, Inc. filed Critical Delphi Technologies, Inc.
Priority to PCT/US2001/005012 priority Critical patent/WO2002066310A1/fr
Publication of WO2002066310A1 publication Critical patent/WO2002066310A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
    • G01D5/244—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
    • G01D5/245—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains using a variable number of pulses in a train
    • G01D5/2454—Encoders incorporating incremental and absolute signals
    • G01D5/2455—Encoders incorporating incremental and absolute signals with incremental and absolute tracks on the same encoder
    • G01D5/2457—Incremental encoders having reference marks
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
    • B62D5/046—Controlling the motor
    • B62D5/0463—Controlling the motor calculating assisting torque from the motor based on driver input

Definitions

  • This disclosure relates to passive starting strategies, and more particularly, to passive starting strategies for a Torque-Ripple-Free Electric Power Steering system.
  • EPS Electric power steering
  • FTPS hydraulic power steering
  • the typical encoding scheme uses at least one encoding track for each of two high-resolution quadrature pulse-trains. In addition, at least three tracks are used for low-resolution commutation sensor signals, which are used for position estimation. It is desirable to reduce the size and cost of the encoder by reducing the number of tracks required on the encoder.
  • the commutation sensors in an EPS system are used only once, immediately following EPS system power-up. The commutation sensors provide some information that helps to provide an assisted torque for starting an EPS motor until the rotor reaches an indexed position.
  • a method for passively starting an EPS system includes disabling assist torque upon power-up, detecting an index pulse upon a movement of a steering column across one of a plurality of reference positions, enabling assist torque for the EPS system upon detecting the index pulse, receiving a variable input torque command indicative of an external steering input, and ramping a variable assist motor torque towards the variable input torque command after enabling assist torque for the EPS system, until the variable assist torque is substantially equal to the variable input torque command.
  • An exemplary EPS system apparatus includes a steering wheel for receiving operator inputs coupled to a steering column, a motor coupled to the steering column for applying torque assist to the column, an encoder coupled to the motor for determining the angular displacement of the steering column where the encoder comprises at least one track (e.g., two tracks) and a set of sensors for sensing the at least one track to generate a set of signals, a controller connected in signal communication between the encoder and the motor for receiving the set of signals from the encoder and controlling the motor in correspondence with a method for passively starting the electric power steering system.
  • the controller comprises an index pulse detector, an enabler responsive to the index pulse detector for enabling an amplifier, and an amplifier for ramping the variable assist torque in correspondence with a variable input torque command.
  • the variable input torque command may correspond to an operator input or to an automatic control signal, such as for hands- free operation.
  • TRF EPS torque-ripple-free electric power steering system
  • Figure 2 illustrates a schematic cross-sectional diagram of a motor of the TRF EPS of Figure 1;
  • FIG 3 illustrates an alternate embodiment sensor arrangement for a TRF EPS system
  • Figure 4 illustrates a sensor arrangement for the TRF EPS system of
  • FIG. 5 illustrates a set of encoder signals for the TRF EPS system of
  • Figure 1 Figure 6 illustrates passive starting for TRF EPS system of Figure 1;
  • FIG. 7 illustrates a flow-chart for passive starting of the TRF EPS system of Figure 1.
  • a torque-ripple-free (“TRF”) electric power steering (“EPS”) system includes a slot-less permanent magnet (“PM”) machine with a sinusoidal back-EMF (“sinusoidal motor”) and an electronic sinusoidal controller for supplying a sinusoidal current in synchronization with the back-EMF waveform.
  • reference numeral 10 generally designates a TRF EPS system for a motor vehicle.
  • a steering mechanism 12 is a rack-and-pinion type mechanism that includes a toothed rack (not shown) and a pinion gear (also not shown) located under a gear housing 14.
  • a steering wheel 16 is coupled to an upper steering shaft 18. As the steering wheel 16 is turned, the upper steering shaft 18, which is connected to a lower steering shaft 20 through a universal joint 22, turns the pinion gear. Rotation of the pinion gear moves the toothed rack, which moves tie rods 24 (only one shown) that, in turn, move steering knuckles 26 (only one shown), which turn wheels 28 (only one shown).
  • EPS assist is provided through an assist unit generally designated by reference numeral 30, which includes a controller 32 and an electric motor 34.
  • the controller 32 is powered by a vehicle power supply 36 through a supply line 38.
  • the controller 32 receives a signal indicative of the vehicle velocity on signal line 40.
  • Steering pinion gear angle is measured by position sensor 42 and fed to the controller 32 tlirough line 44.
  • Position sensor 42 may be an optical-encoding type of sensor, a variable resistance type of sensor, or any other suitable type of position sensor for performing the functions of position sensor 42.
  • the torque sensor 43 senses the torque applied to the steering wheel 16 by a vehicle operator.
  • the torque sensor 43 may include a torsion bar (not shown) and a variable-resistance type of sensor (also not shown) that outputs a variable resistance signal to controller 32 through line 46 in relation to the amount of twist on the torsion bar.
  • the controller 32 sends a command signal through line 48 to the electric motor 34.
  • the motor 34 supplies torque-assist to the steering system through a worm 50 and a worm gear 52, in order to provide a steering torque assist to the vehicle steering system in addition to a steering force exerted by the vehicle operator.
  • Patent Application entitled An Encoder For A Permanent Magnet Sinusoidal Brashless Motor having attorney docket number H-201810, filed on the same day and assigned to the same assignee as the present application; which is incorporated herein by reference.
  • a sinusoidal motor suitable for use in the TRF EPS system of Figure 1 may. contain several new elements and materials that have not been previously combined in a motor.
  • Figure 2 illustrates a cross section of the sinusoidal motor generally designated by the reference numeral 54, as used in the TRF EPS system of Figure 1.
  • the sinusoidal motor 54 includes a new stator 56 with (a) air-gap (slot-less) winding 58, (b) composite iron yoke 60, also acting as a housing; a new rotor 62 with a high energy magnet 64, (c) sinusoidal magnetization of the magnet, (d) molded composite plastic shaft 66, and a new high-resolution position sensor (not shown) with magnetic resistor ("MR") sensing elements and steel wheels (also not shown).
  • MR magnetic resistor
  • TRF EPS is a high-performance drive that meets particular cost limitations. Therefore, a new type of encoder is disclosed that combines high-resolution and low cost.
  • Optical encoders are temperature limited and susceptible to dirt.
  • Semiconductor-based magnetic sensors e.g., magnetoresistors
  • FIG. 3 the basic idea of a position sensor usable for the passive starting method is shown, which includes a two-in-one sensor system 70 using a set of magnetoresistors ("MR") 72, or other suitable magnetic sensors, mounted on a stationary permanent magnet 74.
  • the stationary permanent magnet 74 faces a preferably steel wheel 76 with two tracks, 78 and 80, each of which has teeth and slots on its periphery, as shown.
  • the teeth and slots modulate the magnet's field and thus produce variations in magnetic field, hence the preference for steel though other magnetically conductive or active materials may be substituted therefore.
  • the variations in magnetic field are sensed by the magnetoresistors 72.
  • the several tracks 78 and 80 on the steel wheel 76 allow a sensing mechanism using the set of magnetoresistors 72 to perform several functions at the same time.
  • the high- resolution track 80 provides two incremental signals to enable the generation of sinusoidal currents in the motor.
  • the other track 78 provides an absolute position signal at least once every electrical cycle. This absolute signal is used for generating an index pulse, or for motor commutation in order to direct the current to the appropriate phases, which are particularly important at startup.
  • the steel wheel 76 is mounted on a shaft 82, which is coupled to a rotor (not shown) of a motor (also not shown). It should be appreciated that the two tracks, the high- resolution track 80 and the other track 78 need not to be incorporated in a single structure as described in Figure 3.
  • the HI signal 85 may be generated at a location other than the location of the other track 78 as shown in Figure 3.
  • HI signal 85 is used for the generation of an index signal 90 as will be described in Figure 5.
  • any means that can generate a suitable index signal 90 will suffice for the purposes of the passive starting method.
  • a single sensor system 71 using a single set of magnetoresistors 72 mounted on a stationary permanent magnet 74 can also be used for the passive starting method.
  • the stationary permanent magnet 74 faces a steel wheel 76 with a single track 80, which has teeth and slots on its periphery, as shown.
  • the teeth and slots modulate the magnet's field and thus produce variations in magnetic field.
  • the variations in magnetic field are sensed by the magnetoresistors 72.
  • the single track 80 on the steel wheel 76 allows a sensing mechanism using the set of magnetoresistors 72 to perform several functions at the same time.
  • the single track 80 is a high-resolution track that provides two incremental signals to enable the generation of sinusoidal currents in the motor.
  • the index pulse is then produced by some means such as by building the high resolution track 80 in such a way that one of the incremental pulses look different, once per revolution.
  • the steel wheel 76 is mounted on a shaft that is coupled to a rotor (not shown) of a motor (also not shown).
  • the dimension of the stationary permanent magnet 74 which constitutes a substantial portion of a sensor system, is reduced to about half the volume in Figure 4 as compared to Figure 3. This reduction in dimension is significant because the reduction in size of the stationary permanent magnet 74 results in a concomitant and desirable savings in cost.
  • An encoder for a TRF EPS system has high resolution while keeping the sensor simple enough for economical production. '
  • the features on the wheel periphery are much smaller than the gap between the magnet and the wheel, the magnetic field modulation is insignificant and the signal generated may be too small to be useful.
  • the sensor resolution is therefore proportional to the sensor wheel diameter. In this particular application, a single MR would provide approximately 4 mechanical degrees of resolution, which is considered insufficient. Therefore, several MRs are used to generate additional signals and to thereby increase the resolution to a satisfactory level.
  • the starting procedure for the EPS system is as follows: Upon power-up of the EPS system, the single commutation signal HI 85 is sampled to determine an initial EPS system motor rotor position.
  • Figure 5 illustrates a set of encoder signals for the sinusoidal EPS system.
  • the numeral 84 designates the set of encoder signals.
  • Periodical signals EA 86 and EB 88 are high-resolution quadrature pulse-trains. The pulse-trains are used to determine the EPS motor rotating direction as well as to determine the increment of the EPS motor rotator position count.
  • An index signal 90 is a pulse indicating a predefined, usually zero, EPS motor rotor position that is used for resetting the EPS motor rotator position count. This index signal 90 is generated in response to the single commutation signal HI 85.
  • the method of generating the index signal 90 from the HI signal 85 includes using a hardware circuit and/or software to sample and process the transients in the HI signal.
  • the index signal can be an independent signal produced by a separate sensor and track, or contained in the incremental signals 86 and 88 by building the high resolution track 80 in such a way that one of the incremental pulses looks different once per revolution.
  • Time-mark TO represents the instant that electric power is supplied to the EPS system.
  • the EPS system starts off as being inactive or disabled, in that a motor voltage is zero from time TO to immediately before TI. During this period, the EPS system will not provide any torque assist to the driver's steering, and is waiting for the driver to steer manually to move the motor across the index position.
  • the EPS system encounters, for the first time, the index pulse 90, and immediately enables torque assist for the vehicle operator. To avoid any abrapt transients in assist torque, the EPS system starts ramping during the time interval TI to T2.
  • the TRF EPS starting method is a passive starting strategy for the sinusoidal EPS system.
  • the EPS system does not require the use of all commutation sensors for starting the motor.
  • the need to seek any assisted torque from the motor is disabled for an initial steering wheel movement.
  • the passive starting strategy relies fully on the vehicle operator's efforts in turning the steering wheel 16, which is coupled to the EPS motor, to thereby turn the motor rotor to the index position during a power-up initialization stage.
  • the EPS motor controller 32 provides zero assist torque until the first index pulse is encountered. Upon encountering the first index pulse, the controller 32 ramps the assist torque to a desired level.
  • the passive starting flow-chart is generally indicated by the reference numeral 92.
  • the flow-chart 92 starts at box 94. Once a start-up is detected, an EPS assist torque is set to zero at 96. If an index pulse 90 is detected at decision block 98, the controller 32 then enables assist torque from the EPS system or ramps the assist torque toward normal operating mode 100. If no index pulse 90 is detected, the flow-chart flows back along line 102 to the start of decision block 98 and waits until index pulse 90 is detected.
  • the assist torque is compared with an input torque command such as a derivative of a torque exerted upon the steering wheel 16 by a vehicle operator and transmitted to the steering shaft 18. Once the assist torque is equal or greater than that of the input torque coimnand, the assist torque is set to be equal to the input torque command at block 106. At this juncture, normal operation of the EPS system commences, and the instant passive starting procedure ends at block 108. However, if at decision block 104, the assist torque is less than that of the input torque command, the flowchart flows back along line 110 to the beginning of block 100 and ramping of assist torque continues. For example, see Figure 6 within the time segment of TI to T2.
  • the above flow-chart may be incorporated into a process wherein the process can be added to the existing EPS motor control process.
  • the torque command may be modified.
  • the assist torque is set to zero.
  • the process ramps the assist torque until it reaches the desired value.
  • the EPS system then enters into the normal operation with precise position information.
  • the passive starting process or method assumes that the index pulse signal 90 is generated without utilizing all three commutation signals, HI, H2 and H3. However, the index pulse 90 may be derived from one of the commutation signals, such as for example, HI. If so, at least one commutation sensor has to remain for the generation of the index pulse 90.
  • the single commutation sensor may be used to provide an estimation of the EPS system motor rotor initial position. But the error in this estimation is +90 degrees. This might produce a possible motor torque against the driver's steering effort. Therefore, an assist torque based on such position estimation is generally unsatisfactory for position estimation purposes in a TRF EPS system.
  • the TRF EPS passive starting strategy contemplates detection of an index pulse. Upon the detection of the index pulse, a ramping of a variable-assist torque ensues. The variable-assist torque is then compared with a variable-input torque command. The variable-assist torque preferably converges to the variable- input torque command.
  • the method for passively starting an EPS system may be implemented without the use of commutation signals, or with only one commutation signal if no index pulse is available separately.
  • the method includes detecting an index pulse. Upon the detection of the index pulse, the absolute position of the EPS motor will be obtained and assist torque will be generated by the EPS system. To avoid any abrupt torque transients, a ramping of a variable assist torque ensues. The variable assist torque is then compared with a variable input torque command. The variable assist torque is then set to equal to the variable input torque command.
  • the index pulse or signal 90 need not be derived from a commutation signal.
  • This method substantially reduces the need for commutation signals for a determination of an initial rotor position. It should be appreciated that the method may utilize only two quadrature incremental pulses and an index pulse in order to accomplish a desirable result.
  • the index pulse can be obtained by processing a single commutation signal.
  • the method is intended for application to EPS systems, it may also be applied to any motor that requires a starting process wherein a position of a rotor needs to be determined.
  • Passive starting of a TRF EPS system can be embodied in the form of computer-implemented processes and apparatuses for practicing those processes.
  • Passive starting of a TRF EPS system can also be embodied in the form of computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the disclosed method.
  • Passive starting of a TRF EPS system can also be embodied in the form of computer program code, for example, whether stored in a storage medium, loaded into or executed by a computer, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the disclosed method.
  • the computer program code segments configure the microprocessor to create specific logic circuits.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Power Steering Mechanism (AREA)
  • Steering Control In Accordance With Driving Conditions (AREA)

Abstract

La présente invention concerne un procédé et un appareil permettant de démarrer de manière passive un système de direction par alimentation électrique qui consiste à désactiver le couple d'assistance lors de la mise sous tension (96), à détecter une impulsion (98) d'indexation lors d'un mouvement de la colonne de direction parmi la pluralité des positions de référence, à activer le couple d'assistance destiné au système de direction par alimentation électrique lors de la détection de l'impulsion d'indexation, à recevoir une commande de couple d'entrée variable indicative d'une entrée de direction externe et à augmenter (100) un couple moteur d'assistance variable dans le sens de la commande de couple d'entrée variable après l'activation du système de direction jusqu'à ce qu'il soit sensiblement égal (106) à cette commande de couple d'assistance variable.
PCT/US2001/005012 2001-02-16 2001-02-16 Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple WO2002066310A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US2001/005012 WO2002066310A1 (fr) 2001-02-16 2001-02-16 Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2001/005012 WO2002066310A1 (fr) 2001-02-16 2001-02-16 Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple

Publications (1)

Publication Number Publication Date
WO2002066310A1 true WO2002066310A1 (fr) 2002-08-29

Family

ID=21742343

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2001/005012 WO2002066310A1 (fr) 2001-02-16 2001-02-16 Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple

Country Status (1)

Country Link
WO (1) WO2002066310A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005092689A1 (fr) * 2004-03-23 2005-10-06 Trw Lucasvarity Electric Steering Limited Appareil electrique de direction assistee
US10807633B2 (en) 2017-05-12 2020-10-20 Ka Group Ag Electric power steering assembly and system with anti-rotation coupler
CN111953930A (zh) * 2020-06-19 2020-11-17 窦崧 一种移动式道路监控设备

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5065324A (en) * 1989-03-22 1991-11-12 Fuji Jukogyo Kabushiki Kaisha Method of detecting absolute steering angle of steering angle sensor for vehicle
US5283741A (en) * 1990-06-08 1994-02-01 Valeo Electronique Control apparatus for a vehicle power steering system
US5521475A (en) * 1992-11-25 1996-05-28 Koyo Seiko Co., Ltd. Electric power steering apparatus
US5791432A (en) * 1995-04-19 1998-08-11 Aisin Seiki Kabushiki Kaisha Steering control apparatus for an automotive vehicle
US6079513A (en) * 1997-02-12 2000-06-27 Koyo Seiko Co., Ltd Steering apparatus for vehicle

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5065324A (en) * 1989-03-22 1991-11-12 Fuji Jukogyo Kabushiki Kaisha Method of detecting absolute steering angle of steering angle sensor for vehicle
US5283741A (en) * 1990-06-08 1994-02-01 Valeo Electronique Control apparatus for a vehicle power steering system
US5521475A (en) * 1992-11-25 1996-05-28 Koyo Seiko Co., Ltd. Electric power steering apparatus
US5791432A (en) * 1995-04-19 1998-08-11 Aisin Seiki Kabushiki Kaisha Steering control apparatus for an automotive vehicle
US6079513A (en) * 1997-02-12 2000-06-27 Koyo Seiko Co., Ltd Steering apparatus for vehicle

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005092689A1 (fr) * 2004-03-23 2005-10-06 Trw Lucasvarity Electric Steering Limited Appareil electrique de direction assistee
GB2426493A (en) * 2004-03-23 2006-11-29 Trw Lucasvarity Electric Steer Electric power assisted steering apparatus
GB2426493B (en) * 2004-03-23 2008-04-02 Trw Lucasvarity Electric Steer Electric power assisted steering apparatus
US7664583B2 (en) 2004-03-23 2010-02-16 Trw Lucasvarity Electric Steering Limited Electric power assisted steering apparatus
US10807633B2 (en) 2017-05-12 2020-10-20 Ka Group Ag Electric power steering assembly and system with anti-rotation coupler
CN111953930A (zh) * 2020-06-19 2020-11-17 窦崧 一种移动式道路监控设备

Similar Documents

Publication Publication Date Title
US6329782B1 (en) Method and apparatus for robust generation of an index pulse for an electric power steering system
US6373211B1 (en) Extended speed range operation of permanent magnet brushless machines using optimal phase angle control in the voltage mode operation
US6653829B1 (en) Low cost approach to measuring high resolution rotary position of electric machines
JP4250657B2 (ja) モータの位置を計算する方法
CN100337395C (zh) 电动机温度推定装置和电动机控制装置
JP5789911B2 (ja) 回転角検出装置及び電動パワーステアリング装置
US6914399B2 (en) Active deadtime control for improved torque ripple performance in electric machines
US6460649B2 (en) Passive starting of a torque-ripple-free electric power steering system
CN110539793A (zh) 用于控制线控转向系统的设备和方法
CN102916641A (zh) 多相回转机械控制设备及使用其的电动助力转向系统
US6486658B2 (en) Encoder for a permanent magnet sinusoidal brushless motor in an electric power steering system
CN110497959B (zh) 用于运动控制系统的补偿器防卷绕的系统和方法
US7065437B2 (en) Current limit for an electric machine
JP5151353B2 (ja) 回転角検出装置及びこれを使用した電動パワーステアリング装置
WO2002066310A1 (fr) Demarrage passif d'un systeme de direction par alimentation electrique sans ondulation residuelle de couple
JP4337452B2 (ja) 回転角検出装置及び回転角検出方法
JP2004173372A (ja) モータ制御装置
US7190135B2 (en) Method of inverter linearization in electric machines through secondary modulation
JPWO2019216022A1 (ja) モータ制御装置及びこれを備えた電動パワーステアリング装置
JP2006033928A (ja) ブラシレスモータ
JPH11356079A (ja) Ｓｒモータ及びｓｒモータを用いた電動式パワーステアリング装置
JP6905669B2 (ja) モータ制御装置
WO2008132449A1 (fr) Direction à assistance électrique
JP2004173371A (ja) モータ制御装置
WO2020240877A1 (fr) Détecteur d'angle, dispositif de commande de machine tournante à courant alternatif et dispositif de direction assistée électrique

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): BR JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP