With Zero-crossing Detection (e.g., Polarity Reversal, Etc.) Patents (Class 318/400.35)
  • Patent number: 10523148
    Abstract: A vehicle includes a five-phase electric machine with open windings driven at each side by phase legs of an inverter. A controller monitors for open-circuit windings. In response to detecting an open-circuit winding above a predetermined speed threshold, the controller operates the inverter to drive the windings that are not open-circuited in a square configuration.
    Type: Grant
    Filed: May 8, 2018
    Date of Patent: December 31, 2019
    Assignee: Ford Global Technologies, LLC
    Inventors: Silong Li, Wei Xu, Jiyao Wang
  • Patent number: 10454399
    Abstract: A method and circuit for controlling or starting a U-shape single phase synchronous permanent magnetic motor (U-SPSPM motor) having a rotor and a stator and coupled to a single phase alternating current (AC) power source through a switch, including estimating back electromotive force (back-EMF) of the motor based on an observer model with inputs indicative of the measured signals, and triggering the switch to supply power to the motor based on the estimates of the back-EMF.
    Type: Grant
    Filed: August 10, 2018
    Date of Patent: October 22, 2019
    Assignee: Whirlpool Corporation
    Inventors: Kevin J. Fitzpatrick, Biao He, Qiang Mei, Ying Xiao
  • Patent number: 10381969
    Abstract: A control device comprises a driving unit configured to drive a plurality of coils of a multiple-phase motor by pulse width modulation; a detection unit configured to detect currents flowing through the plurality of coils in a time-division manner; and a change unit configured to change, in accordance with a duty in the pulse width modulation, a sequence of detecting the currents flowing through the plurality of coils by the detection unit.
    Type: Grant
    Filed: February 27, 2018
    Date of Patent: August 13, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Koji Kawamura, Jumpei Ashida, Shigeru Kameyama
  • Patent number: 10236808
    Abstract: The present disclosure provides a system and method to determine at least one parameter of a motor, such as an inductance. The inductance can be determined, such as based on one or more digitally sampled motor winding currents. A digital filter can be applied to the digital samples such as to determine a slope of the motor winding currents. The digital filter can include a least squares fit that can be applied to the digital samples, such as to determine a slope of the motor winding currents. The least squares fit can be determined based on a computation of central tendencies such as an average value of time, an average value of current, an average value of the square of time, and the average value of the product of time and current. The average values can be determined recursively to provide improved computational speed.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: March 19, 2019
    Assignee: Analog Devices, Inc.
    Inventors: Brendan Aengus Murray, Jens Engen Sorensen
  • Patent number: 10199963
    Abstract: A motor driving device and a motor system that can reduce a torque ripple of a motor are provided. The current control loop detects a drive current of the motor, detects an error between the detected value of the drive current and a current indication value as a target value of the drive current, and determines the duty of the PWM signal reflecting the error concerned. The back EMF phase detector detects the phase of a back electromotive force of each phase in the motor. The torque correction unit calculates a first torque correction coefficient of a periodic function based on the phase variations in the three phases of the back electromotive force, and corrects the current indication value superimposing the first torque correction coefficient on the current indication value.
    Type: Grant
    Filed: November 17, 2017
    Date of Patent: February 5, 2019
    Assignee: Renesas Electronics Corporation
    Inventors: Minoru Kurosawa, Kichiya Itagaki
  • Patent number: 10084400
    Abstract: The phase of a drive current of a motor is optimized. The phase arithmetic unit PHCAL calculates a drive voltage phase ?drv to converge the phase difference between the reference voltage phase ?bemf and the reference current phase ?i to zero based on a prescribed arithmetic expression. The phase correction unit PHCP determines the phase ?drvR after the correction by adding a correction value to the phase ?drv, and the magnitude of the correction value is updated by a feedback control so as to converge to a prescribed value the phase difference between the reference voltage phase ?bemf and the reference current phase ?i which are inputted. A PWM controller shifts an energization control timing synchronized with the reference voltage phase ?bemf based on the corrected phase ?drvR, and generates the PWM signal for controlling the drive voltage to a sine wave shape.
    Type: Grant
    Filed: September 15, 2016
    Date of Patent: September 25, 2018
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Minoru Kurosawa, Kichiya Itagaki
  • Patent number: 9634604
    Abstract: An electronic device is for controlling motor drive circuits for driving a multi-phase motor in a force assisted system. Each motor drive circuit selectively permitting current to flow into or out of a respective phase of the multi-phase motor connected to the motor drive circuit in response to being driven by respective control signals. A motor control circuit generates the control signals. A fault processor detects at least one fault condition causing a fault current in a first motor drive circuit. In the event of the fault condition being detected, at least one alternative control signal is generated for at least one motor drive circuit for permitting at least one compensation current to flow for reducing a faulty force due to the fault current.
    Type: Grant
    Filed: April 30, 2013
    Date of Patent: April 25, 2017
    Assignee: NXP USA, Inc.
    Inventor: Wilhard Von Wendorff
  • Patent number: 9496811
    Abstract: The present disclosure provides a device and a method for driving a motor that demonstrates low noise and/or low vibration. A pulse-modulated control pulse signal S2 is generated by a driving signal generation portion 310 at each phase. A driving voltage VU˜VW, with duty cycle corresponding to the control pulse signal S2 and being inserted with specific idle time is applied to coils LU˜LW at each phase. A current phase detection signal S3 indicating a phase of the current IL flowing through the coil LU is generated by the current phase detection portion 330 at a specific phase (the phase U) corresponding to the control pulse signal S2 according to a pulse width of a terminal voltage VU at one end of the coil LU of the phase U.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: November 15, 2016
    Assignee: ROHM CO. LTD.
    Inventor: Kenji Sugiura
  • Patent number: 9438149
    Abstract: A method of controlling a brushless permanent-magnet motor. The method includes dividing each half of an electrical cycle of the motor into a conduction period followed by a primary freewheel period. The conduction period is then divided into a first excitation period, a secondary freewheel period, and a second excitation period. The method then involves exciting a winding of the motor during each excitation period and freewheeling the winding during each freewheel period. The secondary freewheel period has a position and length within the conduction period that acts to reduce the harmonic content of current in the winding relative to back EMF in the winding. As a result, the efficiency of the motor is improved.
    Type: Grant
    Filed: June 13, 2014
    Date of Patent: September 6, 2016
    Assignee: Dyson Technology Limited
    Inventors: Tuncay Celik, Libo Zheng
  • Patent number: 9287812
    Abstract: Motor drives and control methods are presented for sensorless motor speed control in which inverter output currents are sampled from the inverter output and a frequency modulation value is determined based on the current feedback. A speed or frequency setpoint is adjusted at least partially according to the frequency modulation value to provide an adjusted frequency or speed setpoint value that is then used in controlling the inverter to provide stability control to mitigate hunting or motor stoppage.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: March 15, 2016
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Thomas Nondahl, Jingbo Liu, Peter Schmidt, Semyon Royak, Timothy M. Rowan
  • Patent number: 9281812
    Abstract: Provided is a metal-insulator transition (MIT) transistor system including an MIT critical current supply device allowing MIT to occur between a control terminal and an outlet terminal of an MIT transistor for easily and conveniently driving the MIT transistor. A current supplier according to the present invention provides a critical current for allowing an MIT phenomenon to occur between the control terminal and the output terminal of the MIT transistor.
    Type: Grant
    Filed: July 2, 2014
    Date of Patent: March 8, 2016
    Assignee: Electronics and Telecommunications Research Institute
    Inventor: Hyun-Tak Kim
  • Patent number: 9257919
    Abstract: In one aspect of the teachings herein, an interface circuit obviates the need for a microcontroller with multi-channel PWM capability in the context of controlling a brushless, three-phase DC motor. Instead, the interface circuit generates the requisite set of motor-phase control signals using a single PWM channel from the microcontroller. The interface circuit is implemented as a standalone integrated circuit (IC) in one embodiment, and is integrated into a pre-driver circuit in another embodiment.
    Type: Grant
    Filed: October 17, 2013
    Date of Patent: February 9, 2016
    Assignee: Omron Automotive Electronics, Inc.
    Inventor: Lucretiu Pisau
  • Patent number: 9197144
    Abstract: A method and system for controlling a motor is provided. In particular, various embodiments of the present disclosure describe a method and system for controlling a spindle motor in a hard disk drive (HDD) A method of controlling a motor is provided, the motor including a 3-phase synchronous motor with three terminals of an electromagnetic winding configuration. The method includes providing an input voltage between two of the terminals and measures a resultant silent terminal voltage at the third terminal, which is thereafter used in determining a rotor position. A corresponding system for controlling a motor is further provided.
    Type: Grant
    Filed: July 16, 2013
    Date of Patent: November 24, 2015
    Assignee: Marvell International Ltd.
    Inventors: Song Lin, Chao Bi
  • Patent number: 9184680
    Abstract: Motor Drive Control Device configured to properly start up various types of motors under operating conditions where motor operations are performed in a wide range of temperature and power supply voltage, includes output drive controllers that supply PWM drive output signals to an output pre-driver in such a manner as to minimize the error between a current instruction signal and a current detection digital signal. In response to a detected induced voltage generated from a voltage detector upon startup of a motor, an initial acceleration controller supplies initial acceleration output signals specifying a conducting phase for initial acceleration of the motor to the output drive controllers. The initial acceleration controller, the output drive controllers, and an output driver make a conducting phase change and perform a PWM drive to provide the initial acceleration of the motor.
    Type: Grant
    Filed: July 24, 2014
    Date of Patent: November 10, 2015
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventor: Minoru Kurosawa
  • Patent number: 9088235
    Abstract: A method of determining the position of a rotor of a permanent-magnet motor. The method includes sequentially exciting and freewheeling a winding of the motor. The winding is freewheeled for a freewheel period in response to current in the winding exceeding a current limit. The method also includes measuring a parameter that corresponds to either the magnitude of current in the winding at the end of the freewheel period or the interval between the start or end of the freewheel period and the time at which current in the winding exceeds the current limit. The measured parameter is then compared against a threshold and the rotor is determined to be at a predetermined position when the measured parameter is less than or greater than the threshold.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: July 21, 2015
    Assignee: Dyson Technology Limited
    Inventor: Christopher John Bateman
  • Patent number: 9088238
    Abstract: A method of determining the position of a rotor of a permanent-magnet motor. The method uses two different schemes to determine the position of the rotor. A first scheme is used when the rotor rotates within a first speed range, by sequentially exciting and freewheeling a winding of the motor, measuring a parameter that depends on the rate of change of current in the winding, and comparing the parameter against a threshold. A second scheme is used when the rotor rotates within a second speed range, by generating a voltage signal that is proportional to the voltage across the winding, generating a further voltage signal that depends on the rate of change of current in the winding, and comparing the two signals.
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: July 21, 2015
    Assignee: Dyson Technology Limited
    Inventor: Christopher John Bateman
  • Patent number: 9071181
    Abstract: Back electromotive force (BEMF) of a brushless DC (BLDC) motor may be determined when using continuous sinusoidal drive by computing the voltage to common (ground) of each phase (3) thereof when a phase current is substantially zero. These phase voltages may be computed from the DC supply voltage and the duty cycle of the pulse width modulation (PWM) drive to each of the motor phases. From the three phase voltages computed at a zero phase current occurrence, each coil voltage may be calculated. The BEMF of that coil is substantially equal to the coil voltage when at zero current. The phase voltages, when computed at a zero current instance, may be used in determining the BEMF. Once the BEMF is determined it may further be used to regulate the motor speed using a K factor of the BLDC motor.
    Type: Grant
    Filed: June 19, 2013
    Date of Patent: June 30, 2015
    Assignee: MICROCHIP TECHNOLOGY INCORPORATED
    Inventor: Lionel Yersin
  • Publication number: 20150145455
    Abstract: A method is provided for determining a phase current direction and a zero-crossing moment of the phase current in a sinusoidally controlled brushless direct current motor. The brushless direct current motor comprises a coil per phase and the phase of the brushless direct current motor is driven by a half bridge driver. The half bridge driver comprises a high side field effect transistor and a low side field effect transistor. The method comprising the following steps: measuring the drain source voltage over the high side field effect transistor and low side field effect transistor, and determining the zero crossing moment of the phase current by determining the current direction based on the measured drain source voltages and by determining the moment the current changes direction.
    Type: Application
    Filed: November 3, 2014
    Publication date: May 28, 2015
    Inventors: Jan HEYNLEIN, Thomas FREITAG, Christian PAINTZ
  • Patent number: 9041330
    Abstract: A sensorless brushless motor control device includes a first amplification module common to all motor phases and generating an intermediary voltage signal, a voltage divider between each motor phase and a node on which the intermediary voltage signal is generated, and a computation unit. Each voltage divider generates a first corrected electromotive force with a predetermined average value. The computation unit controls the motor on the basis of the first corrected electromotive forces. By using only hardware components, the control device maintains the average of the corrected electromotive forces at the center of the analog acquisition zone of the computation unit.
    Type: Grant
    Filed: March 11, 2013
    Date of Patent: May 26, 2015
    Assignee: DASSYM SA
    Inventor: Jean-Pierre Voillat
  • Patent number: 9035590
    Abstract: There are provided a motor driving apparatus and method, the motor driving apparatus including: a filter controlling unit detecting a frequency of a pulse width modulation (PWM) signal and generating a control signal; a first filtering unit filtering a back electromotive force (BEMF) signal according to the control signal; a second filtering unit filtering a reference signal according to the control signal; and a comparing unit comparing output of the first and second filtering units and generating a motor rotor detection signal.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: May 19, 2015
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventor: Soo Woong Lee
  • Patent number: 9035589
    Abstract: A method for determining a position of an armature of a synchronous machine relative to a stator of the synchronous machine includes the steps of applying to the synchronous machine a plurality of test current vectors, with each test current vector having identical current magnitude and a different angle in relation to an armature-related d,q coordinate system, during application of the test current vectors to the synchronous machine, determining values of a physical response quantity of the armature proportional to the q component of the test current vectors, determining a first harmonic of the determined values of the physical response quantity as a function of the angle, and determining the position of the armature relative to the stator as a zero crossing of the first harmonic where a first derivative of the first harmonic is positive.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: May 19, 2015
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventor: Mihaly Nemeth-Csoka
  • Publication number: 20150123583
    Abstract: A motor driving control apparatus may include a zero cross point (ZCP) detecting unit detecting back electromotive force generated by a motor apparatus and detecting a plurality of zero cross points in the back electromotive force, a zero cross point correcting unit correcting the plurality of zero cross points when a time interval between the plurality of zero cross points is equal to a predetermined error period or longer, and a controlling unit controlling driving of the motor apparatus using the plurality of corrected zero cross points.
    Type: Application
    Filed: May 22, 2014
    Publication date: May 7, 2015
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Joo Yul Ko
  • Publication number: 20150123582
    Abstract: Disclosed herein is a motor driving apparatus, including: an inverter applying a direct current voltage to the respective phases of a brushless DC (BLDC) motor by a switching operation; and a motor driver detecting counter electromotive force patterns in floating sections of the respective phases, detecting zero cross points (ZCPs) of the respective phases using the counter electromotive force patterns, and then generating a PWM signal for controlling a switching operation of the inverter and a phase switching of the respective phases using position information of the zero cross points (ZCPs).
    Type: Application
    Filed: February 26, 2014
    Publication date: May 7, 2015
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Bon Young Gu
  • Patent number: 9000710
    Abstract: A system for determining motor speed of a brush DC motor in an apparatus, including a first filter for receiving a substantially DC component of the motor current and parameters corresponding to the brush DC motor, for calculating a speed estimate thereof; an adaptive bandpass filter having a center frequency corresponding to the speed estimate of the first filter, for receiving the motor current and substantially isolating a periodic current fluctuation thereof; a block for determining a frequency of the periodic current fluctuation, the current fluctuation corresponding to motor speed of the brush DC motor. The adaptive bandpass filter uses debounce filtering to reduce rapid filter passband switching, and a run-in period prior to passband switching to obviate transient effects of filter switching.
    Type: Grant
    Filed: June 11, 2012
    Date of Patent: April 7, 2015
    Assignee: Lexmark International, Inc.
    Inventor: Stefan Mark Atay
  • Publication number: 20150069942
    Abstract: A back electromotive force (BEMF) zero cross may be detected in a brushless direct current (BLDC) motor that is controlled by pulse width modulation (PWM). A phase input of the BLDC motor is tri-stated during PWM periods in which the phase input conducts motor drive current, and the tri-stating of the phase input is used to determine whether a BEMF zero cross has occurred in the BLDC motor.
    Type: Application
    Filed: September 12, 2013
    Publication date: March 12, 2015
    Applicant: Texas Instruments Incorporated
    Inventor: Yisong Lu
  • Publication number: 20150069943
    Abstract: There are provided a motor driving control apparatus, a motor driving control method and a motor system using the same. The motor driving control apparatus includes: a back-electromotive-force detecting unit detecting back electromotive force generated by a motor apparatus; a floating correcting unit, if zero-crossing has not occurred in a current floating area, correcting the floating area by predicting a time at which a zero-crossing occurs; and a control unit determining a zero-crossing time of the back electromotive force based on an output from the floating correcting unit and controlling driving of the motor apparatus using the determined zero-crossing time.
    Type: Application
    Filed: November 21, 2013
    Publication date: March 12, 2015
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Joo Yul KO
  • Publication number: 20150069944
    Abstract: There are provided a motor driving control apparatus, a motor driving control method, and a motor system. The motor driving control apparatus includes: a zero-crossing detecting unit detecting back electromotive force generated in a motor apparatus and detecting a zero-crossing point of the back electromotive force; a commutation point calculating unit calculating an average value for zero-crossing points detected at least three times to determine a commutation point using the calculated average value; and a control unit controlling a phase change of the motor apparatus using the commutation point.
    Type: Application
    Filed: November 21, 2013
    Publication date: March 12, 2015
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Joo Yul KO
  • Publication number: 20150023804
    Abstract: A driving device for a brushless DC motor having at least one coil ma include a voltage zero crossing detection unit to where an induced voltage becomes zero; a detection period setting unit to set at least one detection period synchronously with the voltage zero crossing point; a coil voltage detection comparator to compare a terminal voltage generated from one end of the coil with a threshold voltage, and generate a coil voltage detection signal indicating a comparison result; a current phase detection unit to generate a phase detection signal indicating a relationship between a phase of a coil current flowing through the coil and a phase of the induced voltage; a driving signal synthesis unit to generate a driving control signal based on the phase detection signal; and a driving circuit to drive the brushless DC motor based on the driving control signal.
    Type: Application
    Filed: July 22, 2014
    Publication date: January 22, 2015
    Inventor: Kenji SUGIURA
  • Publication number: 20150002065
    Abstract: A device may detect the zero-cross event of a BEMF of an electric motor with first, second, and third phase windings driven by respective first, second, and third power driving stages. The device may include a control circuit configured to place at an impedance state the third power driving stage relative to the third phase winding, the third phase winding being coupled to a zero-cross detecting circuit, introduce a masking signal to mask an output signal of the zero-cross detecting circuit in correspondence with each rising edge of a first driving signal of the first power driving stage relative to the first phase winding, and determine whether a first duty-cycle of the first driving signal is such that a duration of a masking window of the masking signal is greater than an on-time period of the first driving signal.
    Type: Application
    Filed: June 18, 2014
    Publication date: January 1, 2015
    Inventors: Michele Berto BOSCOLO, Federico MAGNI
  • Patent number: 8917043
    Abstract: A motor control circuit and associated techniques can adjust a phase of a motor drive to keep a rotational reference position of an electric motor at the same relative phase as a zero current in a motor winding at different motor speeds and as the motor accelerates and decelerates. In some embodiments, a particular circuit and technique can be used to detect the zero current in the motor winding.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: December 23, 2014
    Assignee: Allegro Microsystems, LLC
    Inventors: Timothy Reynolds, Chengyi Jin
  • Patent number: 8917044
    Abstract: A motor control circuit and associated techniques detect a zero crossing of a current in a motor winding by detecting a reverse current in a half bridge circuit used to drive the motor winding.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: December 23, 2014
    Assignee: Allegro Microsystems, LLC
    Inventors: Timothy Reynolds, Chengyi Jin
  • Publication number: 20140368139
    Abstract: A controller for a brushless motor that includes a PWM module configured in half-bridge or full-bridge mode. The PWM module outputs control signals for controlling the excitation of a winding of the motor, and one of the duty cycle and the period of the PWM module defines a time at which the winding is commutated.
    Type: Application
    Filed: June 13, 2014
    Publication date: December 18, 2014
    Inventors: Yongji ZHOU, Libo ZHENG, Hanping DAI
  • Patent number: 8912744
    Abstract: A method and apparatus for dynamically adjusting a dead time of a BLDC motor during a phase change detect the winding current of the BLDC motor during the dead time, and terminate the dead time when the winding current is detected to be substantially or close to zero. Thus, the method and apparatus can optimize the dead time and switch the BLDC motor between two phases at a zero-current point, without reducing the maximum rotation speed of the BLDC motor.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: December 16, 2014
    Assignee: Richtek Technology Corp.
    Inventors: Haó-Yu Chang, Pei-Cheng Huang, Wei-Hsu Chang, Kuo-Chung Lee
  • Patent number: 8878480
    Abstract: In sequentially selecting and driving two phases of the three-phase stator windings of a synchronous motor, detect a speed electromotive voltage of a de-energized phase, relate the speed electromotive voltage to rotor position information beforehand, then count rotor position information backward based on the detected the speed electromotive voltage to estimate rotor position; and then detect rotation speed from the change rate of the rotor position information so as to achieve highly accurate position and speed control.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: November 4, 2014
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Yoshitaka Iwaji, Shigehisa Aoyagi, Kazuaki Tobari, Ryoichi Takahata, Masaki Hano
  • Patent number: 8872457
    Abstract: The invention relates to a method for operating an electronically commutated electric machine (2). Alternating phase voltage potentials are applied to the phase conductors of the electric machine (2) for commutation, said phase voltage potentials being generated by a pulse-width modulation so that the height of the applied phase voltage potential is determined by a duty cycle (TV) of the pulse width modulation. In order to determine an instant of a zero crossing of a current induced in a phase conductor, a blanking interval (AT) which represents a time slot, is provided, when no phase current potential is applied to the corresponding phase conductor. A first transition time slot (ÜT1) is provided prior to and/or after the blanking interval (AT) during which the progression of the applied phase voltage potential has a defined first gradient during.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: October 28, 2014
    Assignee: Robert Bosch GmbH
    Inventor: Gerhard Knecht
  • Patent number: 8860345
    Abstract: An electric household appliance (1) having a casing (2); a laundry drum (3) mounted inside the casing (2) to rotate about an axis of rotation; a three-phase asynchronous motor (6) for rotating the laundry drum (3); and a sensorless safety system (7) for determining rotation of the rotor (32), to determine rotation or no rotation of the laundry drum (3). The sensorless safety system (7) is designed to supply three direct currents (las, lbs, Ics) to the three stator power phases (31) during a predetermined time interval (?T), so as to magnetize the rotor (32); to cut off supply of the direct currents (las, lbs, Ics); to determine the time pattern of at least one of the three induced currents (Iar, Ibr, Icr) induced in the stator (30) in response to magnetizing the rotor (32); and to determine rotation or no rotation of the rotor (32) on the basis of the time pattern of at least one of the three induced currents (Iar, Ibr, Icr).
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: October 14, 2014
    Assignee: Electrolux Home Products Corporation N.V.
    Inventors: Enrico Boscariol, Enrico Marson, Paolo Posa
  • Patent number: 8853985
    Abstract: Systems, methods, and other embodiments associated with back-EMF detection for motor control are described. In an embodiment, an apparatus includes a drive circuit configured to apply excitation signals to respective inputs of a motor, a signal inhibit circuit configured to convey a signal to inhibit application of the excitation signals during an interval, and a measuring circuit configured to measure a back-electromotive force (EMF) signal crossing a reference signal during the interval.
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: October 7, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Ravishanker Krishnamoorthy, Foo Leng Leong, Edy Susanto
  • Patent number: 8847530
    Abstract: A permanent-magnet AC motor comprises a motor and a controller coupled to the motor. The motor includes a winding. The controller includes a drive model configured to provide a drive current. Waveform of the drive current is spatially symmetrical. The winding has a waiting zone having electrical angle of 30° and a driving zone having electrical angle of 150° in each half electrical cycle when the motor is in operation. The driving zone is equally divided into five driving sub-zones.
    Type: Grant
    Filed: April 26, 2010
    Date of Patent: September 30, 2014
    Assignee: Fortior Technology (Shenzhen) Co., Ltd.
    Inventor: Lei Bi
  • Patent number: 8847531
    Abstract: A microcontroller determines the position of the rotor of a brushless, direct-current motor by determining the time of zero crossing of back electromotive force (EMF) emanating from the non-driven phase winding. The zero crossing point is determined by interpolating voltage differentials that are time stamped. Each voltage differential is the difference between the phase voltage of the phase winding and the motor neutral point voltage. The time of zero crossing is determined without using a comparator and without interrupting the processor at each zero crossing point. The processor interpolates the time of zero crossing independently of when the zero crossing point occurs. A hold signal conductor is connected both to a sample and hold circuit and to the load input lead of a time stamp register. The microcontroller simultaneously captures a phase voltage in the sample and hold circuit and a timer count in the time stamp register.
    Type: Grant
    Filed: January 11, 2013
    Date of Patent: September 30, 2014
    Assignee: IXYS CH GmbH
    Inventor: Rex L. Allison, III
  • Patent number: 8829834
    Abstract: There are provided a motor driving control apparatus and method, and a motor using the same. The motor driving control apparatus includes: an inverter unit applying a driving current to a motor apparatus according to a driving control signal; a back-electromotive force detecting unit detecting back-electromotive force generated by driving of the motor apparatus; a driving current change unit reflecting a level of the back-electromotive force to determine a resistance value and reflecting the resistance value in the driving current; and a controlling unit performing a control operation to change the driving control signal using the driving current in which the resistance value is reflected and the back-electromotive force.
    Type: Grant
    Filed: February 19, 2013
    Date of Patent: September 9, 2014
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventor: Joo Yul Ko
  • Patent number: 8823304
    Abstract: The invention relates to a method for providing a trigger signal in response to the commutation of a mechanically commutated electric motor (1). The method comprising the steps of providing a mechanically commutated electric motor (1), providing a power supply for said mechanically commutated electric motor via electrical supply leads (10, 11) from power supply circuitry, providing a filter (15) connected to said electrical supply leads (10, 11), detecting with said filter (15) a voltage spike occurring at commutation, outputting from said filter (15) said trigger signal.
    Type: Grant
    Filed: October 10, 2008
    Date of Patent: September 2, 2014
    Assignee: Ideassociates (IOM) Limited
    Inventors: Preben Bo Fich, Curt Michael Petersen Willadsen
  • Publication number: 20140239864
    Abstract: A sensorless motor controller includes a variable link control, including a radiation-hardened field programmable gate array (FPGA) and a back electromotive force (EMF) decoder circuit. The back EMF decoder infers the position of a rotor of the motor. A filter on the decoder conditions the back EMF signal and has multiple cutoff frequencies which can be dynamically controlled by the FPGA in order to compensate for phase shift in the back EMF signal. The FPGA also controls a variable DC link and its digital speed control loop.
    Type: Application
    Filed: February 22, 2013
    Publication date: August 28, 2014
    Applicant: HAMILTON SUNDSTRAND CORPORATION
    Inventors: Harold J. Hansen, Robert P. Wichowski, Kevin G. Hawes, Patrick J. Sears
  • Patent number: 8810180
    Abstract: A method for operating an electric motor with primary and secondary sections, wherein the primary section has a multi-phase exciter winding, each of the phase connections of said exciter winding being connected to an output connection of an end stage, which has controllable semi-conductor switches for applying phase voltages to the output connections, includes the following steps: a) introducing an operating phase by applying the phase voltages to the output connections such that a moving magnetic field is induced in the exciter winding, the moving field effecting a relative motion between the primary and secondary sections, b) hinting off the phase voltage at least one of the output connections to introduce a measurement phase, and c) measuring the electrical back emf induced in the winding strand in order to determine the angular difference between the phase position of the exciter current and that of the back emf.
    Type: Grant
    Filed: October 21, 2009
    Date of Patent: August 19, 2014
    Assignee: Zentrum Mikroelektronik Dresden AG
    Inventor: Franz-Josef Schmidt
  • Patent number: 8796973
    Abstract: In a multi-phase brushless DC motor, a zero crossing N-bit filter includes a comparator and a phase multiplexer. The phase multiplexer connects each motor phase to each of a positive and a negative input of the comparator, with a switch in each connection to form a switch array. A microprocessor is disposed to operate the switches, and is configured to measure a BEMF for a first phase by opening the switches connecting all other phases to the positive input of the comparator and by opening the switch connecting the first phase being measured to the negative input of said comparator. The comparators output is received by a shift register. The microprocessor is configured to respond to a zero crossing when a majority of bits in the shift register change between high and low.
    Type: Grant
    Filed: March 26, 2012
    Date of Patent: August 5, 2014
    Assignee: Hella Corporate Center USA, Inc.
    Inventors: Scott Eugene Bauer, John Andrew Bleecker, III
  • Patent number: 8786231
    Abstract: A driving circuit for a single-phase brushless motor includes: a driving-signal-generating circuit to generate a driving signal for supplying first and second driving currents to a driving coil of the single-phase brushless motor in an alternate manner with a de-energized period therebetween; an output circuit to supply the first or the second driving current to the driving coil in response to the driving signal; and a zero-cross detecting circuit to detect a zero cross of an induced voltage, generated across the driving coil, during the de-energized period, wherein the driving-signal-generating circuit determines a length of a subsequent energized period, based on a driving cycle from a start of an energized period to a time when the zero-cross detecting circuit detects the zero cross, and the zero-cross-detecting circuit starts detection of the zero-cross after a predetermined time period has elapsed from a start of the de-energized period.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: July 22, 2014
    Assignee: Semiconductor Components Industries, LLC
    Inventor: Tsutomu Murata
  • Patent number: 8766580
    Abstract: A method for controlling a discharge pump of a household appliance, including starting a synchronous electric motor that actuates said discharge pump until the synchronism condition is reached, and driving said synchronous electric motor at a steady state through phase control by varying the firing angle (?). In driving said synchronous motor at steady state through phase control, said firing angle (?) is feedback controlled to cancel the phase difference between the mid-point of a zero current plateau of a function of the phase current fed to the electric motor and the zero-crossing point of a counter electromotive force signal (fcem) relative to the same phase. In feedback controlling the firing angle (?), the synchronous electric motor is switched off if the required firing angle (?) exceeds a maximum threshold (?lim), which may result from the operation of the discharge pump in air-water conditions.
    Type: Grant
    Filed: October 7, 2011
    Date of Patent: July 1, 2014
    Assignee: Askoll Holding S.r.l.
    Inventor: Elio Marioni
  • Publication number: 20140176032
    Abstract: There are provided a back electromotive force detection circuit, and a motor driving control apparatus and a motor using the same. The back electromotive force detection circuit includes: a voltage generating unit generating a voltage in inverse proportion to a duty ratio of a pulse width modulation (PWM) signal; a variable amplifier controlling a gain according to the voltage generated by the voltage generating unit, and amplifying back electromotive force according to the controlled gain; and a comparator comparing an output from the variable amplifier with a pre-set reference signal, and outputting a zero-crossing signal of the back electromotive force.
    Type: Application
    Filed: March 11, 2013
    Publication date: June 26, 2014
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Soo Woong LEE
  • Publication number: 20140167668
    Abstract: There are provided a motor driving control apparatus, a motor driving control method, and a motor using the same. The motor driving control apparatus includes a driving signal generation unit, a back electromotive force detection unit, and a frequency controller. The driving signal generation unit may generate a driving control signal for controlling driving of a motor device. The back electromotive force detection unit may detect back electromotive force of the motor device. The frequency controller may provide control to estimate a zero crossing point of the back electromotive force, set a frequency modulation section including the zero crossing point, and modulate a frequency of the driving control signal during the frequency modulation section.
    Type: Application
    Filed: May 17, 2013
    Publication date: June 19, 2014
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Joo Yul KO
  • Publication number: 20140167667
    Abstract: There are provided a motor driving apparatus and method, the motor driving apparatus including a current detecting unit detecting a level of a driving current applied to a motor for each predetermined period, a current comparing unit comparing the level of the driving current detected by the current detecting unit in a previous period and the level of the driving current detected by the current detecting unit in a current period, and a controlling unit adjusting a level of a reference signal compared with a back electro motive force (BEMF) signal of the motor based on an output of the current comparing unit.
    Type: Application
    Filed: May 17, 2013
    Publication date: June 19, 2014
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Joo Yul KO
  • Publication number: 20140152220
    Abstract: There are provided a motor driving control apparatus and method and a motor using the same. The motor driving control apparatus includes: a back-electromotive force detecting unit detecting back-electromotive force of a motor apparatus; a gradient calculating unit calculating a gradient of a waveform of the detected back-electromotive force; and a controlling unit calculating a zero-crossing point of the back-electromotive force using the calculated gradient and controlling driving of the motor apparatus using the calculated zero-crossing point.
    Type: Application
    Filed: February 20, 2013
    Publication date: June 5, 2014
    Applicant: SAMSUNG ELECTRO-MECHANICS CO., LTD.
    Inventor: Joo Yul KO