Constant Motor Current, Load And/or Torque Control Patents (Class 318/432)
  • Patent number: 9013130
    Abstract: An impact power tool includes a motor, a battery, a hammer mechanism and a control apparatus. The motor runs in the same speed no matter what torque level is selected. The motor runs for a total running time which is identical to an impacting time plus a compensative time. The impacting time is decided according to the selected torque level, and the compensative time is decided according to the power of the battery. An impacting time table and a compensative time table are pre-established to decide the impacting time value and the compensative time value. Therefore, the impact power tool always provides the theory torque output of the selected torque even if the battery is low.
    Type: Grant
    Filed: December 3, 2012
    Date of Patent: April 21, 2015
    Assignee: Mobiletron Electronics Co., Ltd.
    Inventor: Chun-Cheng Chen
  • Patent number: 9013133
    Abstract: A method of detecting a stall condition in a stepper motor with very little movement of an instrument pointer coupled to the stepper motor. The stepper motor rotates the instrument pointer in a first direction towards a pointer stop by a plurality of micro-steps. The stepper motor then rotates the pointer in the first direction at least one additional micro-step while monitoring a back electro-motive force (EMF) produced by the stepper motor. If the instrument pointer is abutting the pointer stop, then the stepper motor will be compressed slightly. If the back EMF is below a predetermined threshold, then the stepper motor is in a stall condition. The instrument pointer can then be micro-stepped in a second direction opposite the first direction to a micro-rotor offset value (?ROV) position.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: April 21, 2015
    Assignee: Visteon Global Technologies, Inc.
    Inventor: Ronald Paul Russ
  • Patent number: 9013125
    Abstract: An electric power converter of an electric rolling stock includes: a converter unit (a first electric-power converting unit) that receives a direct-current voltage and outputs a direct-current voltage controlled to a predetermined value; and an inverter unit (a second electric-power converting unit) that is connected to the output side of the converter unit and drives an electric motor. The converter unit includes a converter control unit (a first control unit) that, based on the input voltage thereof, generates an output voltage command that is a control command for controlling the condition of the output voltage of the converter unit.
    Type: Grant
    Filed: August 17, 2009
    Date of Patent: April 21, 2015
    Assignee: Mitsubishi Electric Corporation
    Inventor: Hidetoshi Kitanaka
  • Patent number: 9007007
    Abstract: A handheld machine tool has a drive motor and a supplementary handle which is mounted on the housing of the handheld machine tool and is assigned a drive-torque limitation device, the drive-torque limitation device limiting the drive torque to a torque level below a maximum torque if the supplementary handle is not mounted on the housing.
    Type: Grant
    Filed: December 14, 2012
    Date of Patent: April 14, 2015
    Assignee: Robert Bosch GmbH
    Inventor: Thilo Koeder
  • Patent number: 8994319
    Abstract: An electric motor includes a magnet rotor which is placed with an air gap interposed between it and a stator and has a magnetic pole portion formed from a plastic magnet which swells by hydrogen bonds, an inverter circuit, a DC-voltage conversion portion, a driving logic control portion, a supply current value control portion, a current value designation portion, a reference current value designation portion, and a correlation designation portion, wherein the correlation designation portion determines an average current value by changing the average current value linearly or non-linearly with respect to a reference current value, and the magnetic pole portion absorbs moisture to swell, thereby making the air gap smaller, at higher humidity than a reference humidity.
    Type: Grant
    Filed: December 28, 2011
    Date of Patent: March 31, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventor: Masayuki Takada
  • Patent number: 8994307
    Abstract: Dynamic reconfiguration-switching of motor windings in a motor is optimized between winding-configurations by selectively lowering resistance of a constantly used portion of one of the motor windings. Acceleration is traded off in favor of higher velocity upon detecting the electric motor in the electric vehicle is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.
    Type: Grant
    Filed: March 1, 2013
    Date of Patent: March 31, 2015
    Assignee: International Business Machines Corporation
    Inventors: Allen K. Bates, Nhan X. Bui, Reed A. Hancock, Daniel J. Winarski
  • Patent number: 8988030
    Abstract: This disclosure is drawn to methods, systems, devices and/or apparatus related to power control in applications over long cables. Specifically, the disclosed methods, systems, devices and/or apparatus relate to power control that considers the maximum power available at the end of a long cable (or from a battery) to a load over a broad range of load conditions. Some example systems may include a power supply located at the Earth's surface and a power converter coupled to the power supply via a cable having a first end coupled to the power supply and a second end coupled to the power converter. Some example power converters may be configured to measure the power being consumed by the electrical load in the well, and adjust operating parameter(s) of the electrical load based, at least in part, on the maximum power available at the second end of the cable.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: March 24, 2015
    Assignee: Schlumberger Technology Corporation
    Inventors: Ramon Hernandez Marti, John Parry, Dudi Rendusara
  • Patent number: 8988836
    Abstract: When an abnormality occurs in a refrigeration cycle, the inverter motor provided in the air conditioner is stopped reliably and contacts of the main relay are prevented from degradation and fusion. A power circuit 1 of the air conditioner includes a rectifier circuit RC, a capacitor C (smoothing unit), a main relay 10 provided on a current path between the rectifier circuit RC and the capacitor C, an inverter circuit 30, a microcomputer 100, and a delay circuit 40. The microcomputer 100 has an inverter circuit control unit 110, a main relay opening/closing control unit 120, a waveform forced cut-off unit 130, and a cut-off signal output unit 140.
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: March 24, 2015
    Assignee: Daikin Industries, Ltd.
    Inventors: Hirotaka Saruwatari, Yuuko Nakashita, Nobuyasu Hiraoka, Satoshi Yagi, Hirotaka Doi, Keisuke Shimatani
  • Patent number: 8981700
    Abstract: Provided is a vehicle seat apparatus including drive mechanism for moving configuring elements of a vehicle seat using a motor drive, in order to adjust a posture; control mechanism for controlling the operation of the drive mechanism; a rotation sensor which outputs pulse signals synchronized with a motor rotation; position detection mechanism for detecting a movement position of the configuring elements by counting pulse edges of the pulse signals according to the motor rotation direction; and reverse rotation detection mechanism for estimating that a reverse rotation has occurred in the motor rotation, in a situation where the pulse edges are continuously detected after the motor drive is stopped, if the rotation direction is unchanged, in a case where a motor rotation speed indicated by the pulse edges after the stop becomes faster than the motor rotation speed before the motor drive is stopped.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: March 17, 2015
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Takashi Okada, Soichiro Hozumi, Toshiro Maeda
  • Patent number: 8981706
    Abstract: An electric motor drive apparatus includes multiple inverter sections arranged corresponding to winding sets of a motor, multiple relays that controls power supplies to the inverter sections, and a control unit. Each inverter section and corresponding winding set are referred to as a system. The control unit includes an obtaining section that obtains a winding current, a determination section that determines a fault occurrence, a specifying section that specifies a faulty system in which the fault occurs, an interrupting section that controls the relay corresponding to the faulty system to interrupt the power supply to the faulty system, and a vibrating section that controls the inverter section of a properly-operating system to add a vibration to an output torque from the electric motor. The vibrating section gradually increases a vibration component of the vibration added to the output torque from the electric motor.
    Type: Grant
    Filed: May 28, 2013
    Date of Patent: March 17, 2015
    Assignee: Denso Corporation
    Inventor: Nobuhiko Uryu
  • Patent number: 8981686
    Abstract: An electric motor controller is configured to be coupled to an electric motor. The controller includes an inverter and a control unit coupled to the inverter. The inverter is configured to receive an input voltage and to provide a conditioned output voltage to the electric motor. The control unit is configured to control the electric motor to produce positive torque when direct current (DC) link voltage has a 100% voltage ripple. Methods for controlling an electric motor using the electric motor controller are also provided.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: March 17, 2015
    Assignee: Regal Beloit America, Inc.
    Inventors: Roger Carlos Becerra, Ludovic Andre Chretien, Glen C. Young, David Allen Clendenen, Yao Da
  • Patent number: 8983730
    Abstract: An electric motor has a stator and a rotor that are used in common between two systems. An ECU controls the motor torque by supplying drive electric power to the motor coils independently of each other. When the ECU determines that the vehicle is traveling on a uneven road, the ECU causes the electric motor to perform a braking operation by short-circuiting at least two phases of the electric motor of one of the two systems that is other than the system that is executing a torque control of controlling the assist torque according to the steering torque and the vehicle speed.
    Type: Grant
    Filed: September 28, 2011
    Date of Patent: March 17, 2015
    Assignee: JTEKT Corporation
    Inventor: Hiroshi Suzuki
  • Patent number: 8981703
    Abstract: A system for operating an electric machine includes: a rotor position sensor to provide a rotor position indication as a function of a rotor position angular range which indicates the position of a rotor of the electric machine; a control unit designed to associate in each case a commutation angular range, which indicates a certain control state for the stator coils, with one or more of the rotor position indications, so that a change in the commutation angular range is triggered by a change in the rotor position indication, and to change an association scheme of the associations between the rotor position indications and the respective commutation ranges as a function of a predefined rotational direction indication which indicates the desired rotational direction.
    Type: Grant
    Filed: January 25, 2011
    Date of Patent: March 17, 2015
    Assignee: Robert Bosch GmbH
    Inventor: Volker Bosch
  • Patent number: 8981697
    Abstract: The motor monitoring system of the present disclosure uses several calculated monitoring values to determine a status of a motor and take a predetermined action when a threshold corresponding with the monitoring value is exceeded. The threshold may be calculated by an intelligent electronic device (IED) monitoring the motor. The predetermined action may include further monitoring of the motor. The predetermined action may include monitoring equipment not directly monitored by the IED.
    Type: Grant
    Filed: October 4, 2012
    Date of Patent: March 17, 2015
    Assignee: Schweitzer Engineering Laboratories, Inc.
    Inventor: Mark L. Zeller
  • Patent number: 8981696
    Abstract: Dynamic reconfiguration-switching of motor windings in an electric motor in an electric vehicle is optimized between winding-configurations. Acceleration is traded off in favor of higher velocity upon detecting the electric motor in the electric vehicle is at an optimal angular-velocity for switching to an optimal lower torque constant and voltage constant. The total back electromotive force (BEMF) is prohibited from inhibiting further acceleration to a higher angular-velocity.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: March 17, 2015
    Assignee: International Business Machines Corporation
    Inventors: Allen Keith Bates, Nhan Xuan Bui, Reed Alan Hancock, Daniel James Winarski
  • Patent number: 8973452
    Abstract: In a body of an electric actuator, dust collecting pipes are disposed as a pair along an axial direction of a hole portion of the body. The dust collecting pipes are connected respectively to negative pressure supply ports provided in an end block, and include plural first through fifth suction holes separated mutually along an axial direction of the dust collecting pipes. Distances between the first through fifth suction holes are formed so as to become smaller stepwise from one end side of the dust collection pipes, on the side of the negative pressure supply ports, to the other end side thereof.
    Type: Grant
    Filed: November 29, 2012
    Date of Patent: March 10, 2015
    Assignee: SMC Kabushiki Kaisha
    Inventors: Yoshihiro Fukano, Shoichi Makado, Hiroyuki Shiomi
  • Patent number: 8970152
    Abstract: An exemplary power supply assembly includes a drive device having a bus capacitor. A switch associated with an input side of the drive device selectively connects the drive device to a power supply. An inductor has an impedance that limits an amount of current supplied to the bus capacitor during an initial charging of the bus capacitor when the switch connects the input side of the drive device to the power supply. A restrictive circuit portion dampens a resonance effect of the inductor. The restrictive circuit portion has a resistance that allows the bus capacitor to charge quickly. The impedance of the inductor has a more significant effect on how quickly the bus capacitor charges than an effect of the resistance. A dampening factor of the restrictive circuit controls a voltage of the bus capacitor during the charging of the bus capacitor.
    Type: Grant
    Filed: July 30, 2010
    Date of Patent: March 3, 2015
    Assignee: Otis Elevator Company
    Inventors: Daryl J. Marvin, Michael Mann, Steven M. Millett
  • Patent number: 8965610
    Abstract: Apparatus and method for controlling an electric motor providing assistance to a bicycle rider based on measuring the mechanical power generated by the rider. The power generated by the rider is measured by measuring tension in a bicycle chain (or belt) and RPM. A chain (or belt) roller is carried at the free end of a cantilevered beam and the chain (or belt) rides over the roller. The resulting deflection of the cantilevered beam provides a measurement of chain tension. A control signal for the electric motor is generated based on a smoother version of the power generated by the rider.
    Type: Grant
    Filed: May 19, 2012
    Date of Patent: February 24, 2015
    Inventor: Thomas Boyle
  • Patent number: 8964338
    Abstract: A system includes a refrigerant compressor including an electric motor, a current sensor that measures current flow to the electric motor, a switching device configured to close and open to allow and prevent current flow to the electric motor, respectively, a maximum continuous current (MCC) device that includes a resistance corresponding to a maximum continuous current for the electric motor, and a motor protection module. The motor protection module communicates with the MCC device, the current sensor, and the switching device and determines a first MCC value for the electric motor as a function of the resistance of the MCC device. The motor protection module also selectively sets a predetermined MCC to the first MCC and controls the switching device based on a comparison of the current flow to the electric motor and the predetermined MCC.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: February 24, 2015
    Assignee: Emerson Climate Technologies, Inc.
    Inventors: Frank S. Wallis, Joseph James Rozsnaki
  • Patent number: 8963460
    Abstract: A method for controlling a motor is provided. The method comprises obtaining electrical signals of the motor with a signal unit, the electrical signals comprising a motor torque and an angular velocity, calculating a voltage phase angle of a voltage vector with a calculating component, wherein a command torque, the motor torque, the angular velocity and a voltage amplitude of the voltage vector are inputs of the calculating component, and wherein the voltage phase angle is a variable and the voltage amplitude is a constant. The method further comprises modulating the voltage phase angle and the voltage amplitude to a switching signal for controlling an inverter; converting a direct current voltage to the voltage vector according to the switching signal, and applying the voltage vector to the motor.
    Type: Grant
    Filed: November 9, 2012
    Date of Patent: February 24, 2015
    Assignee: General Electric Company
    Inventors: Yong Li, Pengju Kang, Ronghui Zhou, Xiangming Shen, Xiao Chen, Zili Cai, Tong Zhao
  • Patent number: 8947031
    Abstract: A method for operating a direct current (DC) motor is shown and described. The method includes using pulse width modulated (PWM) DC output to control the speed of the DC motor. The method further includes sensing current output to the motor. When the sensed current exceeds a threshold, the method holds the PWM DC output off.
    Type: Grant
    Filed: June 26, 2012
    Date of Patent: February 3, 2015
    Assignee: Johnson Controls Technology Company
    Inventors: Russell W. Diamond, Gary A. Romanowich, David R. Fuhr
  • Patent number: 8941338
    Abstract: An electric braking device for printing material processing machines includes at least one electric drive to be braked that is supplied by a power converter in motor operation and is braked by the power converter in generator operation. A control unit switches on a redundant electric braking device in the case of a failure of the power converter by using a switch. The braking device has at least two braking stages, an additional switch for actuation in at least two stages, and at least one brake resistor. In the circuit of the redundant electric braking device, a braking current is measured and the measured value is fed to a comparator for comparing the actual braking current to a desired braking current. A printing press having the braking device is also provided.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: January 27, 2015
    Assignee: Heidlelberger Druckmaschinen AG
    Inventors: Reiner Villhauer, Klaus-Dieter Kleibaumhueter, Josef Reiter, Andreas Schulz
  • Patent number: 8928266
    Abstract: An electric drive system includes a motor output shaft rotating on a motor axis and a first electric motor. The system includes an epicyclical gear that includes a sun gear, a ring gear, a plurality of planet gears and a carrier. The sun gear, the ring gear and the carrier gear of the epicyclical gear all rotate on the motor axis, and the carrier gear is connected to the motor output shaft via a first flange. The system also includes a second electric motor interposed between the first electric motor and the epicyclical gear. The second motor shaft has a hollow center along the motor axis and the first motor shaft extends through the hollow center of the second motor shaft and is connected to the sun gear. The system also includes a second flange. The second flange connects the second motor shaft to the carrier. The first flange and the second flange are located at opposite sides of the epicyclical gear.
    Type: Grant
    Filed: September 29, 2013
    Date of Patent: January 6, 2015
    Inventor: William Chin-Woei Lin
  • Patent number: 8922147
    Abstract: A quiet motor control system is described. This system digitally determines modulated voltages applied to motor phases in a manner that compensates for winding torque distortions, which reduces acoustic emissions.
    Type: Grant
    Filed: May 1, 2013
    Date of Patent: December 30, 2014
    Assignee: Texas Instruments Incorporated
    Inventors: John K. Rote, Brian L. Schmidt, Gregory E. Swize
  • Patent number: 8917037
    Abstract: The power circuit comprises a voltage conversion part converting an input voltage entered in accordance with a voltage of a power source to generate an output voltage and outputting the generated output voltage to the motor and a current detection part outputting a first signal in accordance with a current flowing through a given part of the power circuit. The voltage conversion part lowers the voltage value of new output voltage being generated when the current detection part outputs the first signal.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: December 23, 2014
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Kazuhiko Funabashi, Nobuhiro Takano
  • Patent number: 8912745
    Abstract: A method for operating a drive motor of a drive system, including the following: providing a control variable, which is ascertained as a function of one or multiple state variable(s) of the drive system and as a function of a default variable, to an output stage for operating the drive motor; reading the control variable previously provided to the output stage back from the output stage to obtain a read-back control variable; ascertaining a back-calculated torque from the read-back control variable; comparing the back-calculated torque and a predefined monitoring torque; and providing the control variable or an alternative control variable ascertained from the monitoring torque to the output stage as a function of a result of the comparison for the purpose of operating the drive motor.
    Type: Grant
    Filed: October 23, 2012
    Date of Patent: December 16, 2014
    Assignee: Robert Bosch GmbH
    Inventors: Christian Ruland, Oliver Heim
  • Patent number: 8907608
    Abstract: Disclosed are alternate embodiments of various components of a barrier operator system. and methods of operation, including of the mechanical drive subsystem with segmented and self-locking rail unit, rail mounting supports, belt and chain drive tensioning, and drive assembly carriage and interface; the electronics and software routines for controlled operation of the various barrier operator functions; wall console communications with the barrier operator; encryption and decryption of access codes; establishment and monitoring of travel limits and barrier speed and force profiles; thermal protection of barrier operator drive motors; and establishment and control of communications from the barrier operator to accessories by way of a wireless adapter.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: December 9, 2014
    Assignee: Overhead Door Corporation
    Inventors: Leroy G. Krupke, Mark Kenneth Siegesmund, Mark Raymond Wilzbach
  • Patent number: 8901874
    Abstract: An electric power steering system calculates a motor resistance Rm using a resistance map, and calculates an estimated inducted voltage based on a motor current and a motor voltage. If the estimated induced voltage is determined as being equal to or smaller than a determination value that is set in accordance with the current level, the electric power steering system calculates a motor resistance (estimated motor resistance Rma) and updates the resistance map based on the estimated motor resistance Rma.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: December 2, 2014
    Assignee: JTEKT Corporation
    Inventors: Kozo Niimi, Yuji Kariatsumari
  • Patent number: 8901869
    Abstract: A method of controlling speed of an electric machine having a rotor and a stator is provided. The method may comprise the steps of monitoring a desired speed and a measured speed of the rotor, generating a torque command based on the desired speed and the measured speed, and controlling phase current to the stator based on a hybrid closed loop analysis of the torque command, the measured speed and an estimated position of the rotor. The estimated rotor position may be derived at least partially from the desired speed.
    Type: Grant
    Filed: July 31, 2012
    Date of Patent: December 2, 2014
    Assignee: Caterpillar Inc.
    Inventors: Jackson Wai, Jesse Gerdes, James Michael Thorne
  • Patent number: 8896248
    Abstract: A control system for a motor includes an inverter coupled to the motor. The control system further includes a microcontroller coupled to the inverter. The microcontroller includes a processor programmed to measure an input voltage and acquire a back EMF voltage of the motor. The processor is also programmed to control the inverter to regulate the motor voltage based on the input voltage and the back EMF voltage to facilitate controlling the motor.
    Type: Grant
    Filed: July 27, 2011
    Date of Patent: November 25, 2014
    Assignee: Regal Beloit America, Inc.
    Inventors: Roger Carlos Becerra, Ludovic Andre Chretien, Mark A. Brattoli, Glen C. Young
  • Patent number: 8892296
    Abstract: [Problem] An object of the present invention is to provide a power state diagnosis method and a power state diagnosis apparatus that pass and increase not only a d-axis current but also a q-axis current to a current value that a steering behavior does not occur to perform a diagnosis in the vector control of a motor, and determine that a power supply degraded, that the power supply is normal and that the diagnosis is not completed without giving an uncomfortable feeling to a driver, detecting a timing that there is not a driver, and needing to comprise a plurality of actuators.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: November 18, 2014
    Assignee: NSK Ltd.
    Inventors: Hirokazu Abe, Yoshiki Ninomiya, Toru Sakaguchi
  • Patent number: 8890452
    Abstract: A control device for an electrically driven door is provided that can enhance the sensitivity of detection of a door pinch state and that can prevent a passenger from being pressed when the door pinch state occurs. The control device includes a driving force instruction value producing unit that outputs a driving force instruction value of the electrically driven door, a state observing unit that estimates a mechanical resistant force to a door driving system, a reference model that determines a dynamic characteristic of the electrically driven door to the mechanical resistant force estimated by the state observing unit, a gain compensator that computes a control compensation value that makes an output of the reference model coincide with an actual speed of the electrically driven door; and an adder that adds the control compensation value computed by the gain compensator to the driving force instruction value.
    Type: Grant
    Filed: July 2, 2012
    Date of Patent: November 18, 2014
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Satoru Ozaki
  • Patent number: 8892280
    Abstract: A sprung mass damping control system of a vehicle, which aims to suppress sprung mass vibration generated in a vehicle body of a vehicle provided with at least a motor-generator (first and second motor-generators) as a drive source, includes a sprung mass damping control amount calculating device that sets a sprung mass damping control amount for suppressing the sprung mass vibration, and a drive source control device (a motor-generator control device) that executes sprung mass damping control by controlling a motor-generator control amount of the motor-generator to realize the sprung mass damping control amount.
    Type: Grant
    Filed: May 11, 2010
    Date of Patent: November 18, 2014
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Gohki Kinoshita, Koichiro Muta, Toshiya Hashimoto, Eiji Fukushiro, Takanori Aoki, Akihiro Kimura, Shunsuke Oyama, Masaya Yamamoto, Kaiji Itabashi, Yoshitaka Oikawa, Takashi Saito
  • Patent number: 8892281
    Abstract: A control system for an electric vehicle has a vehicle speed calculation section that calculates a speed of the electric vehicle and a control unit that controls an inverter of an electric motor to provide road wheels with a predetermined reference torque in accordance with a manipulated value of an accelerator pedal, wherein the unit has a reference torque correction section that changes the reference torque from an original value and then returns the changed reference torque to the original value when a calculated speed of the electric vehicle is in a given speed range.
    Type: Grant
    Filed: March 21, 2012
    Date of Patent: November 18, 2014
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Keisuke Suzuki, Masahiro Nakamizo
  • Patent number: 8884576
    Abstract: A variable-flux motor drive system including a permanent-magnet motor including a permanent magnet, an inverter to drive the permanent-magnet motor, and a magnetize device to pass a magnetizing current for controlling flux of the permanent magnet. The permanent magnet is a variable magnet whose flux density is variable depending on a magnetizing current from the inverter. The magnetize device passes a magnetizing current that is over a magnetization saturation zone of magnetic material of the variable magnet. This system improves a flux repeatability of the variable magnet and a torque accuracy.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: November 11, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuaki Yuuki, Kazuto Sakai, Hiroshi Mochikawa
  • Patent number: 8885315
    Abstract: A multi-actuator motion control system includes a control methodology that coordinates the motion of multiple actuators while limiting the force-fight between the actuators. Control logic is provided in a relative coordinate system that allows control of the mean actuator position. Force-fight between the actuators is decoupled from the actuator position by estimating load forces on the actuator using reduced-order observers.
    Type: Grant
    Filed: October 15, 2009
    Date of Patent: November 11, 2014
    Assignee: Hamilton Sundstrand Corporation
    Inventor: Michael C. Harke
  • Patent number: 8884557
    Abstract: A method for operating a mains-operated electric motor for a power tool includes connecting a first side of an electric motor to a first mains and connecting a second side of the electric motor to a second mains using first and second switches, respectively, in particular semiconductor switches, and monitoring the operational reliability of the switches using an electronic controller for operating safety.
    Type: Grant
    Filed: December 10, 2010
    Date of Patent: November 11, 2014
    Assignee: Robert Bosch GmbH
    Inventor: Hans Hermann Rottmerhusen
  • Patent number: 8872450
    Abstract: The power circuit comprises a voltage conversion part converting an input voltage entered in accordance with a voltage of a power source to generate an output voltage and outputting the generated output voltage to the motor and a current detection part outputting a first signal in accordance with a current flowing through a given part of the power circuit. The voltage conversion part lowers the voltage value of new output voltage being generated when the current detection part outputs the first signal.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: October 28, 2014
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Kazuhiko Funabashi, Nobuhiro Takano
  • Patent number: 8860349
    Abstract: The invention relates to a method of safety cutoff of an electromechanical motor vehicle power steering, in which safety switches (26, 27, 28) are provided for electrical separation of a servomotor from a control system or a vehicle electrical system, wherein the following steps are provided: a) receiving a fault signal in a control system (30); b) sending a switch-off signal via control lines (31, 32, 33) to the safety switches (26, 27, 28); c) checking the electrical voltages present on the safety switches (26, 27, 28); d) deciding whether the switch-off signal on each safety switch (26, 27, 28) has led to switch-off; e) if the switch-off signal on one or more safety switches (26, 27, 28) has not led to switch-off, switching those safety switches (26, 27, 28) back on, which could not be switched off; f) repeating steps b) to e) until all safety switches have been switched off successfully (26, 27, 28).
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: October 14, 2014
    Assignee: ThyssenKrupp Presta AG
    Inventor: Zoltan Baranyai
  • Patent number: 8860356
    Abstract: A variable magnetic flux motor drive system includes: a variable magnetic flux motor having a variable magnet which is a low-coercive permanent magnet; an inverter that drives the variable magnetic flux motor 1; an inverter as a magnetization unit which supplies a magnetization current for controlling a magnetic flux of the variable magnet; and a boosting unit boosting an input DC voltage to a predetermined target value to output it to the inverter. The variable magnetic flux motor drive system makes it possible to achieve size reduction and high efficiency, while securing a voltage required for supplying a magnetization current when controlling the magnetic flux of the variable magnet.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: October 14, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuaki Yuuki, Kazuto Sakai, Hiroshi Mochikawa
  • Patent number: 8860348
    Abstract: A hybrid powertrain system has a high-voltage electric circuit including a high-voltage battery and a DC link coupled to first and second inverters electrically connected to first and second torque machines. A method for operating the hybrid powertrain system includes receiving a motor torque command for the second torque machine, determining a preferred DC link voltage for achieving the motor torque commanded from the second torque machine, selectively interrupting electric power flow between the high-voltage battery and the DC link to achieve the preferred DC link voltage.
    Type: Grant
    Filed: September 2, 2010
    Date of Patent: October 14, 2014
    Assignee: GM Global Technology Operations LLC
    Inventors: Peter J. Savagian, Sean E. Gleason, James E. Tarchinski, Mohammad N. Anwar
  • Patent number: 8855826
    Abstract: Vibration in a mechanical system driven by a motor connected to a load is reduced by providing an angular position and an angular velocity of the motor to a linear feedback term and to a nonlinear feedback term. Outputs of the linear feedback term and the nonlinear feed term, and an optimal feedforward term determined off-line are summed to produce a summed signal, which is fed back to control a torque of the motor.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: October 7, 2014
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Mouhacine Benosman, Vijay Shilpiekandula, Scott A. Bortoff
  • Patent number: 8836260
    Abstract: A method for controlling a specific electric machine includes receiving with a controller a back electromotive force (BEMF) coefficient for the specific electric machine. The controller is configured to control operation of an inverter coupled to the electric machine where the inverter is configured to provide or receive multi-phase electricity to or from the electric machine in motor mode or generator mode, respectively. The method further includes receiving with the controller an input related to a selected torque to be applied by or a selected power to be removed from the electric machine. The method further includes determining a first electrical parameter the inverter is to apply to in motor mode or a second electrical parameter the inverter is to convert power to in generator mode using the BEMF coefficient, and applying the first electrical parameter to the electric machine or converting the received power to the second electrical parameter.
    Type: Grant
    Filed: November 7, 2012
    Date of Patent: September 16, 2014
    Assignee: Remy Technologies, L.L.C.
    Inventor: David A. Fulton
  • Patent number: 8833485
    Abstract: A battery-powered portable tool, such as a chainsaw, hedge trimmer or handheld drill, comprising: a housing (1), a driven element (2) supported by the housing (1), an electric motor (6) coupled to the driven element (2) so as to drive the driven element (2), a battery (5) electrically coupled to the motor (6) so as to supply electric current to the motor (6) and a control circuit (8) arranged to control the supply of electric current to the motor (6) from the battery (5), in which the control circuit (8) comprises a main switch (8) operable by a user and an auxiliary switch (10, 11) also operable by a user; in which the control circuit (8) has: an active state in which operation of the main switch (8) by the user allows electric current to flow to the motor (6) so as to cause the driven element (2) to be driven; and an inactive state in which operation of the main switch (8) does not allow electric current to flow to the motor (6) and so the motor (6) does not drive the driven element (2); in which operation
    Type: Grant
    Filed: April 8, 2009
    Date of Patent: September 16, 2014
    Assignee: Husqvarna AB
    Inventors: Johan Svennung, Pär Martinsson, Johan Björnlinger
  • Patent number: 8829828
    Abstract: A controller device for controlling a power converter device of an electrical generator during rotation of the electrical generator includes a signal converter which is configured to receive an angle signal and in response hereto transposes a current feedback onto two axes of a rotating d, q-reference frame. Further, a current controller has a regulator receiving a d-axis feedback and a d-axis demand and provides in response hereto a d-axis response operative in reducing the difference between the d-axis feedback and the d-axis demand. An error unit provides an error signal indicative of an angle error of the rotating reference frame on the basis of the d-axis response of the d-axis regulator.
    Type: Grant
    Filed: January 9, 2012
    Date of Patent: September 9, 2014
    Assignee: Siemens Aktiengesellschaft
    Inventor: Paul Godridge
  • Patent number: 8829837
    Abstract: A driving apparatus for an electromagnetic load, said apparatus having at least one pair of first and second transistors arranged so as to form a current path with the electromagnetic load for discharging the current produced by the electromagnetic load. The first transistor has an inherent diode between the non-drivable terminals and the apparatus is configured to control switching of the pair of first and second transistors, to diode-connect the second transistor, with said first and second transistors switched off, so that the current produced by said electromagnetic load, crossing said inherent diode, creates an overvoltage between the terminals of the second diode-configured transistor such to exceed the conduction threshold voltage thereof.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: September 9, 2014
    Assignee: STMicroelectronics S.r.l.
    Inventor: Ezio Galbiati
  • Patent number: 8823301
    Abstract: A device and method to determine the stopping rotor position of a washing machine motor includes an inverter, a permanent magnet synchronous motor, and an electronic motor controller. The controller determines the stopped rotor position of the motor by measuring induced currents in the stator field coils of the motor. While the motor is de-energized and slowly rotating, the controller directs the inverter to connect all of the stator field coils of the motor together. The stator field coils may be connected to a common D.C. rail, output from an A.C.-D.C. converter of the washing machine. In an embodiment, the controller determines the rotor position based on the polarities of current induced in the stator field coils. In another embodiment, the controller determines the rotor position based on the phase angle and angular frequency of the three phase currents, transformed into a stationary reference frame.
    Type: Grant
    Filed: November 5, 2012
    Date of Patent: September 2, 2014
    Assignee: Whirlpool Corporation
    Inventors: Biao He, Qiang Mei
  • Patent number: 8823298
    Abstract: A method of operating a laundry treating appliance to control a rotational speed of a drum to move the laundry within the drum according to a predetermined category of movement.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: September 2, 2014
    Assignee: Whirlpool Corporation
    Inventors: Biao He, Qiang Mei, Fabio E. Rosa
  • Patent number: 8823334
    Abstract: A method for starting an electric motor, the motor having a main machine, exciter, and permanent magnet generator (PMG), each having a stator and a rotor, with each rotor mounted to a common shaft, the method comprising starting the main machine in an asynchronous mode by applying a starting current to the stator of the main machine to induce a damper current in a damper winding of the main rotor to generate a starting torque that initiates the rotation of the common shaft, and then running the main machine in synchronous mode by supplying running current from the exciter rotor to the main machine rotor.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: September 2, 2014
    Assignee: GE Aviation Systems LLC
    Inventors: Hao Huang, Xiaochuan Jia
  • Patent number: 8823300
    Abstract: An electric motor control device includes a control section adapted to control supply of a drive current to an electric motor, and a rotational speed detection section adapted to detect a rotational speed of the electric motor, the drive current includes a d-axis current and a q-axis current, and the control section calculates a q-axis current command value based on a torque command value to the electric motor, calculates a d-axis current command value using a difference between the rotational speed of the electric motor and a previously determined base rotational speed of the electric motor, and the q-axis current command value, and performs vector control on the electric motor using the d-axis current command value and the q-axis current command value.
    Type: Grant
    Filed: September 15, 2011
    Date of Patent: September 2, 2014
    Assignee: Seiko Epson Corporation
    Inventor: Isamu Sejimo