Pluse Width Modulation Or Chopping Patents (Class 318/811)
  • Publication number: 20110181232
    Abstract: A system includes a target speed module and a pulse-width modulation (PWM) control module. The target speed module is configured to provide a first waveform based on a first speed setting for a motor. A start of a first cycle of the first waveform corresponds to at least one of a first current or a first voltage. The PWM control module is configured to shift a phase of the first waveform by a torque angle adjustment value to generate a second waveform. A start of a first cycle of the second waveform corresponds to at least one of a second voltage or a second current. The second voltage is greater than the first voltage, and the second current is greater than the first current. The PWM control module is configured to control the motor based on the second waveform.
    Type: Application
    Filed: January 21, 2011
    Publication date: July 28, 2011
    Inventors: Ravishanker Krishnamoorthy, Edy Susanto, Cheng Yong Teoh, Foo Leng Leong
  • Patent number: 7983060
    Abstract: The invention relates to a method for reducing the idle current requirement of a base frequency clocked supply side converter (1) on idle and with low motor loads, provided with controllable semiconductors (T1,T2,T3,T4, T5,T6), wherein the base frequency clocking of the semiconductor switches (T1,T2,T3,T4,T5,T6) occurs depending on the desired direction of flow of power. A converter (1) for carrying out said method is also disclosed.
    Type: Grant
    Filed: February 21, 2007
    Date of Patent: July 19, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventor: Norbert Benesch
  • Patent number: 7969039
    Abstract: A controller is capable of executing direct couple control that directly couples a first power device and a second power device without causing a DC/DC converter to convert voltage. During the direct couple control, a drive signal that causes no voltage conversion is intermittently output to at least one of a plurality of switching devices.
    Type: Grant
    Filed: January 15, 2009
    Date of Patent: June 28, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventors: Naoyuki Mimatsu, Yasushi Kojima, Seigo Murashige, Yutaka Asano
  • Patent number: 7960930
    Abstract: In the rectangular-wave voltage control mode, torque feedback control, in which the voltage phase of the rectangular-wave voltage is adjusted based on the deviation of the torque estimated value from the torque command value, is performed. A torque estimation portion calculates the torque estimated value using the motor currents calculated based on the values detected by a current sensor and a rotational position sensor, as in the case of the PWM control mode. Namely, the same state quantity (quantity detected by the sensors) of the alternating-current motor is used in the motor control in both the rectangular-wave voltage control mode and the PWM control mode.
    Type: Grant
    Filed: November 24, 2006
    Date of Patent: June 14, 2011
    Assignee: Toyata Jidosha Kabushiki Kaisha
    Inventor: Ryoji Sato
  • Patent number: 7956558
    Abstract: An automatic traction control system is provided for an electric or hybrid-electric vehicle. The automatic traction control system may be used with vehicles using two separately excited motors where the armatures of the motors are connected in series to provide differential control. The automatic traction control system monitors and compares the voltages across the armatures of the two motors. If the voltage differential exceeds a predetermined threshold, it is determined that one of the wheels is spinning and current is diverted from the motor driving the spinning wheel to the motor driving the non-spinning wheel.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: June 7, 2011
    Assignee: PG Trionic, Inc.
    Inventors: Ian Dirk Cull, Christian Charles Elie Peyla
  • Patent number: 7952310
    Abstract: A controller of a multi-phase electric motor includes a drive section for driving the multi-phase electric motor, a single current detection section for detecting a current value of the multi-phase electric motor, a pulse width modulation signal (PWM) generation section for generating a PWM signal of each phase based on the current value detected by the current detection section and a saw-tooth signal having a predetermined frequency, a current detectability determination section for determining whether or not the current value is detectable in the current detection section based on the PWM signal of each phase generated by the PWM signal generation section, and a switching number determination section for determining whether or not conducting number of the upper arm switching element is an even number or an odd number based on the determination that the current is not detectable by the current detectability determination section.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: May 31, 2011
    Assignee: OMRON Corporation
    Inventor: Masamitsu Hamasaki
  • Patent number: 7948206
    Abstract: Disclosed is an assembly encompassing a three-phase machine and a frequency converter. Said assembly has the following characteristics: the three-phase machine comprises a stator and a rotor; at least the three circuits of the stator and/or the rotor can be operated in an insulated manner relative to each other for the three phases of the rotary current while being connectable to one separate terminal point of the frequency converter, respectively, so as to be insulated relative to each other; and the frequency converter is embodied with a D.C. link having a grounded neutral in such a way that a voltage or current which is symmetric regarding the potential to ground can be output at any moment between the two associated terminal points of each circuit.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: May 24, 2011
    Assignee: AB SKF
    Inventors: Frank Buschbeck, Martin Groeschl, Gerwin Preisinger, Andreas Jagenbrein
  • Patent number: 7936142
    Abstract: A drilling device prevents recurrence of an overload condition after occurrence of the overload condition, thereby improving operability and safety in the drilling device. A motor for rotating a drill is connected to an AC power source through a motor control unit, a current detector, and a power switch. A magnet is also connected to the AC power source through the power switch and a full-wave rectifier. The motor control unit rotationally drives the motor on the basis of a signal sent from a main control unit according to a state in which a motor start switch is on. The main control unit controls the motor control unit to gradually reduce a supply voltage to the motor when the motor becomes overloaded, to gradually increase the voltage to the normal power supply condition when the overload condition is vanished, and to stop power supply to the motor if the overload condition continues for a predetermined period.
    Type: Grant
    Filed: December 13, 2006
    Date of Patent: May 3, 2011
    Assignee: Nitto Kohki Co., Ltd.
    Inventors: Kenji Otsuka, Osamu Asano
  • Patent number: 7928686
    Abstract: An electric motor control device includes a direct current power source; an inverter interposed between an electric motor and the direct current power source, the inverter device controlling an exchange of electric power therebetween; an inverter control unit that generates PWM pulses having a duty ratio corresponding to voltage command signals and sends the PWM pulses to the inverter in order to switch the inverter; a frequency changing unit that changes a carrier frequency of the PWM pulses generated by the inverter control unit in a manner corresponding to a frequency control signal; and a motor control unit.
    Type: Grant
    Filed: October 31, 2008
    Date of Patent: April 19, 2011
    Assignee: Aisin AW Co., Ltd.
    Inventors: Subrata Saha, Isao Fujiwara, Keisuke Nishimura, Kazuma Hasegawa, Yoshinori Oono, Seiichi Kinugasa
  • Patent number: 7923961
    Abstract: A vehicle includes a motor for driving wheels WH, an inverter to drive the motor, and a control device to perform PWM control of the inverter. The control device performs synchronous PWM control in a case where an electric current supplied to the motor by the inverter or torque generated in the motor is larger than a threshold value; and performs the synchronous PWM control or non-synchronous PWM control in a case where the electric current or the torque is smaller than the threshold value and sets carrier frequency or a pulse number of the PWM control to be higher than the case where the electric current or the torque is larger than the threshold value. Thereby, it is possible to provide a vehicle of achieving reduction of noise, reduction of cost and improvement of fuel consumption in a balanced manner.
    Type: Grant
    Filed: July 22, 2009
    Date of Patent: April 12, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Naoyoshi Takamatsu, Masaki Okamura
  • Patent number: 7917017
    Abstract: If a PWM duty instruction D1 determined by a duty calculation circuit exceeds an upper limit value, a duty signal processing circuit in a motor drive apparatus divides a switching current supply period in each of the phases into a first current supply period and a second current supply period. In the first current supply period, the duty is set to the upper limit value. In the second current supply period, the duty is set to 100%, and the length of the second current supply period is set depending upon the duty instruction.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: March 29, 2011
    Assignee: DENSO CORPORATION
    Inventor: Atsushi Kanamori
  • Patent number: 7915845
    Abstract: A motor control method and a motor control device are provided. The control method includes the steps of receiving a current feedback signal from a coil switching circuit, while the motor is rotating, for generating a separate signal, and comparing the current feedback signal and the separate signal for generating a motor control signal so as to control the operation of the motor.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: March 29, 2011
    Assignee: Delta Electronics, Inc.
    Inventors: Chung-Hung Tang, Chin-Fa Chiu, Chun-Lung Chiu
  • Patent number: 7911177
    Abstract: An overmodulation PWM controller includes a voltage instruction calculation unit which calculates a d axis voltage instruction and a q axis voltage instruction in which a voltage amplitude exceeds a peak value of a triangular wave carrier; a voltage instruction correction unit which corrects the d axis voltage instruction and the q axis voltage instruction so that a pulse width modulation voltage applied to an AC motor has a fundamental wave amplitude corresponding to the voltage instruction amplitude, according to the synchronization value K which is the number of the triangular carriers per one cycle of the phase voltage instruction; and a voltage instruction conversion unit which converts the corrected d axis voltage instruction and the q axis voltage instruction into a phase voltage instruction. The pulse width modulation voltage is controlled according to the result of comparison between the phase voltage instruction and the triangular wave carrier.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: March 22, 2011
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hiroki Ohtani, Hideto Hanada, Makoto Nakamura, Kenji Yamada
  • Patent number: 7906929
    Abstract: An aspect of the invention is a method and a device for controlling a rotating field machine having several phase windings, which can be controlled by means of pulse width modulation, wherein a pulse width modulation controller is adapted in such a way that an individual winding of the phase windings of the rotating field machine is energized at a specifiable sampling time.
    Type: Grant
    Filed: January 24, 2008
    Date of Patent: March 15, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventors: Uwe Krause, Uwe Nolte, Jan Spannberger
  • Patent number: 7898197
    Abstract: A motor control device includes a motor current detector for detecting motor current flowing in a three-phase motor based on current flowing between an inverter driving the motor and a DC power supply, a specified voltage vector generating portion for generating a specified voltage vector indicating a voltage vector to which an applied voltage to the motor should follow based on a magnetic flux linkage of an armature winding of the motor, a specified voltage vector correcting portion for correcting the generated specified voltage vector, and a magnetic flux estimating portion for estimating the magnetic flux linkage based on the motor current and the specified voltage vector after the correction. The motor control device controls the motor via the inverter in accordance with the specified voltage vector after the correction.
    Type: Grant
    Filed: July 24, 2008
    Date of Patent: March 1, 2011
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Yoshio Tomigashi
  • Patent number: 7898211
    Abstract: The circuit structured to drive a motor is provided. The circuit includes: a division signal generator that generates a division signal dividing each of a high level period and a low level period of a binary position signal representing a relative position of a magnetic coil to a permanent magnet into a preset number of multiple divisions; a pulse width setter that sets a pulse width for PWM control corresponding to each of the multiple divisions represented by the division signal; and a PWM signal generator that performs PWM control with the set pulse width, thereby generating a PWM signal as a driving signal for driving the motor.
    Type: Grant
    Filed: September 3, 2008
    Date of Patent: March 1, 2011
    Assignee: Seiko Epson Corporation
    Inventor: Kesatoshi Takeuchi
  • Patent number: 7898210
    Abstract: After an AC motor generates a three-phase current, modulate the three-phase current to generate an original voltage space vector, and add three detecting vectors with a sum of zero after the original voltage space vector. While adding the three detecting vectors, sample the current to generate a sampling result. Then adjust the width of pulses generated by a pulse width modulator according to the sampling result.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: March 1, 2011
    Assignee: Prolific Technology Inc.
    Inventors: Tung-Chin Hsieh, Kuang-Yao Cheng
  • Patent number: 7893650
    Abstract: A multiphase current sensing method wherein the sum of the phase currents is zero including: sensing a.c. and/or d.c. currents in first and second phases; sensing a.c. current in a predetermined a.c. frequency range in a third phase; and combining the current sensed in the first and third phases and the second and third phases and determining a gain correction factor to be applied to the currents sensed in the first and second phases.
    Type: Grant
    Filed: January 29, 2008
    Date of Patent: February 22, 2011
    Assignee: Azure Dynamics, Inc.
    Inventor: Beat J. Arnet
  • Patent number: 7885044
    Abstract: A cooling system is provided with a motor drive device, a fan motor, and a Hall element. The motor drive device includes a lock protection circuit and a lock controller. When a control signal instructing rotation of the fan motor that is to be driven instructs stoppage of the motor for a predetermined time-period or longer, the lock controller has the lock protection circuit inactive. At an occasion when the control signal has continued to instruct stoppage of the fan motor for a first time-period or longer, a standby controller starts time measurement, and after a further predetermined second time-period has elapsed, makes at least a part of the motor drive device transition to a standby mode.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: February 8, 2011
    Assignee: Rohm Co., Ltd.
    Inventor: Tomofumi Mishima
  • Patent number: 7880428
    Abstract: A controller for an induction motor includes a storage device which stores values in a plurality of addresses, a first counter which transits circularly among first to N-th states, a second counter which transits circularly among first to fourth states, a calculating section which calculates calculation values, and a signal generation section which generates PWM signals and synchronous interruption signals at constant time pitch such that pulse widths of the PWM signals are adjusted based on the calculation values respectively. An inverter supplies electric power to an induction motor based on the PWM signals. The first counter transits from one to next of the first to N-th states synchronously to each of the synchronous interruption signals. The second counter transits from one to next of the first to fourth states synchronously to each transition of the first counter from the N-th state to the first state.
    Type: Grant
    Filed: July 23, 2008
    Date of Patent: February 1, 2011
    Assignee: Renesas Electronics Corporation
    Inventor: Sumiyuki Kamikisaki
  • Patent number: 7880427
    Abstract: A two-stranded electronically commutated DC motor has a permanent-magnet rotor (36), power supply terminals (28, 30) for connecting the motor to a current source (22) and a stator (102) having a winding arrangement which includes first and second winding strands (52, 54). The latter are controlled by respective first and second semiconductor switches (70, 80). The motor also has a third controllable semiconductor switch (50), arranged in a supply lead from one of the terminals (28, 30) to the winding strands (52, 54), which third switch is alternately switched on and off by applying to it a PWM (Pulse Width Modulated) signal 24. During switch-off intervals, magnetic flux energy stored in the motor causes a decaying loop current (i2) to run through the windings, continuing to drive the rotor. This facilitates conformal mapping of temperature information in the PWM signal onto a target motor rotation speed.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: February 1, 2011
    Assignee: EBM-PAPST St. Georgen GmbH & Co. KG
    Inventors: Claus Föll, Frank Jeske, Arnold Kuner, Jens Löffler
  • Patent number: 7878766
    Abstract: A method and apparatus for a pump and a pump control system. The apparatus includes pistons integrally formed in a diaphragm and coupled to the diaphragm by convolutes. The convolutes have a bottom surface angled with respect to a top surface of the pistons. The apparatus also includes an outlet port positioned tangentially with respect to the perimeter of an outlet chamber. The apparatus further includes a non-mechanical pressure sensor and a temperature sensor coupled to a pump control system. For the method of the invention, the microcontroller provides a pulse-width modulation control signal to an output power stage in order to selectively control the power provided to the pump. The control signal is based on the pressure within the pump, the current being provided to the pump, the voltage level of the battery, and the temperature of the pump.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: February 1, 2011
    Assignee: SHURflo, LLC
    Inventors: Humberto V. Meza, Nikhil Jitendra Gandhi, Quang Minh Truong
  • Patent number: 7872435
    Abstract: A motor control apparatus provided with an inverter for successively commutating the current to a motor using a PWM signal; a PWM signal generating device for generating the PWM signal using a carrier signal; a rotational state quantity sensor for detecting a rotational state quantity; a phase difference detecting device for detecting the phase difference between the carrier signal and the rotational period based on the rotational state quantity; a frequency setting device for setting a frequency of the carrier signal to a value in accordance with a multiplier for one period in terms of electrical angle of the rotational period of the motor, when the rotational frequency is equal to or greater than a specified frequency and the phase difference is equal to or less than a specified value; and a synchronizing device for synchronizing a control period of the carrier signal to the rotational period.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: January 18, 2011
    Assignee: Honda Motor Co., Ltd.
    Inventors: Nobuyuki Imai, Yoshinari Murayama, Junji Inoue
  • Patent number: 7859210
    Abstract: In order to prevent a short circuit of top and bottom arms of a motor driving IC when noise is added to six control signals for controlling six switching elements, there is provided a semiconductor device for driving a motor, being sealed with resin as one package and comprising: six switching elements for driving a three-phase motor; three output terminals for outputting voltages to the three-phase motor; at least one driving circuit for driving the six switching elements; three control signal input terminals; and a function) of generating six control signals for control of the six switching elements based on three control signals inputted through the three control signal input terminals.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: December 28, 2010
    Assignees: Hitachi, Ltd., Hitachi Information & Control Solutions, Ltd.
    Inventors: Kenji Sakurai, Hiroyuki Hasegawa, Tomoyuki Utsumi, Shoichi Ohozeki, Daisuke Maeda, Mitsuhiro Mishima
  • Patent number: 7855901
    Abstract: An AC command voltage obtained by compensating a reference value of a commercial AC voltage output from a multiplication unit using an FB control unit is multiplied by k (0?k?1) by a multiplication unit and output to a first inverter control unit, and the remaining part is output to a second inverter control unit. The first and second inverter control units generate signals, based on command voltages obtained by superposing the AC command voltage from an AC output control unit on respective phase command voltages.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: December 21, 2010
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Hichirosai Oyobe, Makoto Nakamura, Tetsuhiro Ishikawa, Shigenori Togashi
  • Patent number: 7852022
    Abstract: A control apparatus for an electric car, including a power converter which feeds AC power of variable voltage and variable frequency to a primary side member of a linear electromagnetic actuator, voltage command means for giving a command of a voltage which is fed to the linear electromagnetic actuator, current detection means for detecting current information which flows between the power converter and the linear electromagnetic actuator, and motor constant calculation means for calculating a motor constant of the linear electromagnetic actuator on the basis of the voltage information Vu given by the voltage command means and the current information Iu detected by the current detection means.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: December 14, 2010
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masaki Kono, Tsuneyasu Kakizaki
  • Patent number: 7852028
    Abstract: Analog control of the pulse width used to control the speed of a voice coil motor may be implemented using a “constant-current-charging-capacitor” configuration where the time needed to charge the capacitor is directly related to how far the actual motor speed is from the target speed. The BEMF voltage, indicative of motor speed, is sampled, and then stored in a storage capacitor, which is allowed to charge/discharge to a target voltage level. The time required to charge/discharge the capacitor to the target voltage is directly proportional to the difference between the BEMF voltage and the target voltage, and may be used directly as the pulse width (i.e., the charging time) in the PWM velocity control system. To avoid larger capacitors, a pulse multiplier circuit can be added, allowing charging/discharging the sampled voltage to the target voltage to be repeated by a number, N, of times.
    Type: Grant
    Filed: June 2, 2008
    Date of Patent: December 14, 2010
    Assignee: Marvell International Ltd.
    Inventors: Jye Sheng Hong, Siew Yong Chui
  • Patent number: 7852032
    Abstract: A selector selects an analog signal group to be used for PWM control out of a plurality of analog signals output by a PWM controlled load. An AD converter AD converts the analog signal group and generates a digital signal group that becomes control data for duty ratio setting in a duty ratio setting register to provide the generated digital signal group to a control unit for controlling a PWM circuit. A duty ratio comparison circuit compares duty ratios set by the plurality of duty ratio setting registers. An AD conversion channel selection circuit controls an analog signal group selecting operation by the selector based on a comparison result of the duty ratio comparison circuit.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: December 14, 2010
    Assignee: Panasonic Corporation
    Inventor: Katsuji Azuma
  • Patent number: 7847500
    Abstract: Control technique of a synchronous motor capable of suppressing rotation pulsation caused by individual difference without complicating control algorithm is provided. A pulsation generator superimposing a pulsation component anticipated in advance to a current command for the synchronous motor and a correction current generator superimposing a correction signal substantially having an average value of zero to the current command are provided in a synchronous motor control device. By this configuration, the correction signal suppressing a distortion component is superimposed to a value of the current command with a simplified control configuration. Torque pulsation is suppressed by determining the correction signal from difference between a detection current and a command current.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: December 7, 2010
    Assignee: Renesas Technology Corporation
    Inventors: Yoshitaka Iwaji, Junnosuke Nakatsugawa, Yasuhiko Kokami, Minoru Kurosawa
  • Patent number: 7843671
    Abstract: A drive system for an electrical machine is provided. The system includes a control unit and a monitoring unit, which is independent of the control unit. The control unit includes a device that converts one or more incoming operating parameters of the electrical machine to an output value. The monitoring unit includes a device that converts the operating parameters to a comparison value, with the conversion being carried out more quickly in the control unit than in the monitoring unit. A comparator compares the output value or an intermediate value of the output value with the comparison value of the output value or of the intermediate value.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: November 30, 2010
    Assignee: Daimler AG
    Inventors: Lothar Rehm, Thomas Von Raumer
  • Patent number: 7839103
    Abstract: A driver for a motor in a device includes a reference generator to generate a reference value. A clock management module receives a plurality of clock signals. Each clock signal has a corresponding frequency that is different relative to the corresponding frequency of another clock signal. A clock management module selects a different clock signal of the plurality of clock signals for output from the clock management module at different times during operation of the device. A ramp generating module generates a ramp signal in accordance with the corresponding frequency associated with the selected clock signal. A first pulse width modulation module receives the reference signal and the ramp signal. The first pulse width modulation module outputs a first pulse width modulation driver signal for driving the motor based on the reference signal and the ramp signal.
    Type: Grant
    Filed: May 6, 2009
    Date of Patent: November 23, 2010
    Assignee: Marvell International Ltd.
    Inventors: Sakti P. Rana, Foo Leng Leong, Cheng Yong Teoh
  • Patent number: 7834568
    Abstract: The method and a related device are for driving a brushless motor, according to which by acting solely on the control value, that is by reducing or increasing it, the driving mode eventually passes from a sinusoidal three-phase driving mode to a distorted square-wave three-phase driving mode for increasing or maximizing the voltage that may be supplied to each motor winding or vice versa. An effective drive voltage profile includes, cyclically, during each 60 electrical degree interval, profiles of re-constructed outphased complete drive waveforms including a first one stably in a saturated region, a second one exiting, at the beginning of the interval, a state of incipient saturation, and a third one reaching, at the end of the interval, a state of incipient saturation. In this way, by modifying the numerical control value it is possible to pass from a sinusoidal drive mode to a distorted drive mode of enhanced maximum peak value or vice versa.
    Type: Grant
    Filed: July 18, 2008
    Date of Patent: November 16, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Ezio Galbiati, Michele Cassiano
  • Patent number: 7835630
    Abstract: An integrated circuit for controlling a DC motor is disclosed. The integrated circuit includes at least one digital position and speed circuit (DPS) for providing measurements of speed, position, and direction of the motor, the DPS being in signal communication with the motor for receiving a pair of signals having a quadrature relationship; and at least one programmable gain amplifier (PGA) electrically coupled to the motor, the PGA being configured to receive a feedback signal indicative of current flowing through the motor and to apply a second signal to the motor for adjusting the speed of the motor; and at least two analog-to-digital converters (A/D), one A/D being used to quantize the output of the PGA for an off-chip processor; and another A/D to provide motor reference position from an analog sensor, such as a potentiometer; and at least two digital-to-analog converters (D/A), one D/A used to set the motor voltage; and another D/A used to set the motor current limit.
    Type: Grant
    Filed: April 3, 2008
    Date of Patent: November 16, 2010
    Assignee: The Johns Hopkins University
    Inventors: Peter Kazanzides, Ndubuisi John Ekekwe, Ralph Etienne-Cummings
  • Patent number: 7830104
    Abstract: The brushless motor includes a coil array, a magnet array, a magnetic sensor, a drive control circuit for driving the coil array, and a temperature sensor for detecting a detection target temperature associated with either the coil temperature or the driving element temperature. The drive control circuit reduces the effective value of driving voltage supplied to the coil array when coil temperature detected by the temperature sensor has exceeded a prescribed threshold value.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: November 9, 2010
    Assignee: Seiko Epson Corporation
    Inventor: Kesatoshi Takeuchi
  • Patent number: 7825621
    Abstract: Provided is a motor controller and method of controlling a motor with an improved maximum junction temperature rating. In accordance with one aspect of the present invention, a motor is controlled by varying a common mode voltage duty ratio for a plurality of solid state switching devices in a power inverter, generating drive signals for the solid state switching devices based at least in part upon the common mode voltage duty ratio, and changing states of the solid state switching devices based upon the drive signals.
    Type: Grant
    Filed: August 28, 2007
    Date of Patent: November 2, 2010
    Assignee: Rockwell Automation Technologies, Inc.
    Inventors: Lixiang Wei, Russel J. Kerkman
  • Patent number: 7825622
    Abstract: A load driving device controls two motors by PWM signals. When a standard duty ratio of the PWM signals is 50% and a level of a drive instruction is the standard duty ratio, the standard duty ratio are output to the respective motors to provide a reverse phase relationship that the PWM signal of the standard duty ratio does not overlap. A continuous off-period and the standard PWM signal output when the level of the drive instruction is lower than the standard, and the continuous on-period and the standard PWM signal output when the level of the drive instruction is higher than the standard are changed over at the ratios corresponding to the level of the drive instruction.
    Type: Grant
    Filed: February 12, 2010
    Date of Patent: November 2, 2010
    Assignee: DENSO CORPORATION
    Inventor: Kouji Nakamura
  • Patent number: 7825623
    Abstract: In an electric vehicle drive apparatus having an electric motor and a motor drive device, the electric motor having a stator, a rotor and a moving mechanism capable of changing a relative distance between the stator and the rotor to vary an effective magnetic flux of the motor, the motor drive device compares a regenerative current with a target current during a regenerative control of the motor, and when it is found that the regenerative current is larger than the target current, the distance between the stator and the rotor is increased to reduce the effective magnetic flux.
    Type: Grant
    Filed: April 4, 2008
    Date of Patent: November 2, 2010
    Assignee: Mitsuba Corporation
    Inventor: Kenya Yanagihara
  • Patent number: 7821224
    Abstract: A voltage estimation system for motor control feedback is described. The system may include one or more control modules which may generate voltage commands. An overmodulation or “clipping” module receiving a voltage command can generate a clipped voltage. Rather than measuring directly, a voltage estimator may estimate the clipped voltage based on the duty cycle command to the inverter. This estimated voltage may then be used by a flux estimator to estimate a flux value. Other embodiments are described and claimed.
    Type: Grant
    Filed: April 10, 2008
    Date of Patent: October 26, 2010
    Assignee: Tesla Motors, Inc.
    Inventors: Andrew David Baglino, Troy Adam Nergaard, Heath Hofmann
  • Patent number: 7812564
    Abstract: A supply current control circuit controls the voltage of a low-voltage direct-current power source so that the average current of an inverter circuit detected by a current detecting circuit becomes constant at a specified current value. Accordingly, characteristics that are little in the amount of change of air volume are obtained.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: October 12, 2010
    Assignee: Panasonic Corporation
    Inventor: Masayuki Takada
  • Patent number: 7804266
    Abstract: A motor control device includes a current detecting portion that detects current flowing between an inverter for driving a three-phase motor and a DC power supply for supplying DC voltage to the inverter, a current estimator that estimates a current vector of the motor on a rotating coordinate that rotates along with rotation of a rotor of the motor. The motor control device detects motor current flowing in the motor by using one of a detecting result of the current detecting portion and an estimation result of the current estimator, so as to control the motor via the inverter based on the detected motor current. The current estimator estimates the current vector based on the motor current detected in the past and a specified voltage value, for example.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: September 28, 2010
    Assignee: Sanyo Electric Co., Ltd.
    Inventor: Yoshio Tomigashi
  • Patent number: 7796867
    Abstract: A drive circuit of a fan motor is provided. In an embodiment of the drive circuit, a first PWM comparator compares a temperature detection voltage with a cyclic voltage, and outputs a first PWM signal. A second PWM comparator compares a minimum frequency setting voltage indicating a minimum frequency of the fan motor, with the cyclic voltage, and outputs a second PWM signal. The drive circuit combines the first PWM signal and the second PWM signal by a logical operation, to drive the fan motor. The drive circuit includes a first logic gate which generates a logical sum of the first PWM signal and the second PWM signal, and a second logic gate which generates a logical product of the first PWM signal and an inverted signal of the second PWM signal. The drive circuit switches drive mode based on the first logic gate and the second logic gate.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: September 14, 2010
    Assignee: Rohm Co., Ltd.
    Inventors: Satoshi Miyajima, Hiroaki Hayashi, Tomofumi Mishima
  • Patent number: 7791304
    Abstract: A method for determining duty-cycles of respective pulse width modulated (PWM), space vector modulated (SVM) control signals of an inverter, may include storing values of the duty-cycles as a function of a position of the multi-phase electric load in a look-up table. The method also may include determining a phasor angle representing applied sinusoidal voltages. The method also may include determining the duty-cycles as a function of the angle, and storing, in the look-up table, values of two pre-established waveforms relative to at least one duty-cycle as a function of the angle in at least two 60° degree angular sectors, by at least, identifying which of six 60° angular sectors the angle belongs, calculating a difference between the angle and an angular sector lower bound, and generating values as a function of the identified angular sector of the difference and the two pre-established waveforms stored in the look-up table.
    Type: Grant
    Filed: January 16, 2008
    Date of Patent: September 7, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Francesco Pirozzi, Maurizio Di Meglio, Stefano Baratto
  • Patent number: 7786687
    Abstract: A motor control strategy for a motor in a front steering system for a vehicle that reduces vibrations from the motor being transferred to a vehicle hand-wheel. The control strategy also includes operating the electric motor in a commutation freeze mode if a position error signal is less than a first predetermined threshold by sending signals to coils of the motor to prevent to the motor from rotating, operating the electric motor in a commutation normal mode if the position error signal is greater than a second predetermined threshold that is greater than the first predetermined threshold, and operating the electric motor in an angle step mode if the position error signal is between an intermediate threshold and the second threshold where the angle step mode provides a signal to the motor to move the motor forward or backward a predetermined number of motor steps, one step at a time.
    Type: Grant
    Filed: April 25, 2008
    Date of Patent: August 31, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Chandra S. Namuduri, Suresh Gopalakrishnan, Robert R. Bolio, Ross Feller, Balarama V. Murty
  • Patent number: 7768228
    Abstract: Methods and systems for converting direct current (DC) power to alternating current (AC) power are provided. A first phase of the AC power is generated based on a first carrier signal. A second phase of the AC power is generated based on a second carrier signal.
    Type: Grant
    Filed: September 12, 2007
    Date of Patent: August 3, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Lateef A. Kajouke, Brian A Welchko
  • Patent number: 7768227
    Abstract: A control method and a control system for single phase induction motors driven by two-power electronic switch inverter are disclosed. The system fulfills two main tasks i.e. precise motor speed control and maximum motor efficiency control over wide ranges of motor load and speed command without a motor speed feedback.
    Type: Grant
    Filed: April 26, 2008
    Date of Patent: August 3, 2010
    Inventors: Sadegh Vaez-Zadeh, Bijan Zahedi
  • Patent number: 7768224
    Abstract: The present invention is aimed at provision of a control apparatus for and a control method of controlling a motor for a vehicle driven by a driving circuit that operates according to a pulse width modulation (PWM) signal. Measurement of a duty of an output signal from the driving circuit is executed, and a difference between the measured duty and a target duty in a PWM control is then obtained to further execute setting of a correction value for correcting the target duty based on the above difference and to generate the PWM signal based on the corrected target duty.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: August 3, 2010
    Assignee: Hitachi, Ltd.
    Inventor: Tetsuro Tamura
  • Patent number: 7755320
    Abstract: A motor driving integrated circuit includes a data receiving circuit, a control circuit, and a pulse generating circuit. The data signal receiving circuit receives data signals inputted via a data signal input terminal. The control circuit controls the motor driving integrated circuit based on a first data signal received through the data signal receiving circuit. The pulse generating circuit generates a pulse signal for PWM (Pulse Width Modulation)—controlling a motor coil based on a second data signal received through the data signal receiving circuit. The pulse generating circuit includes a rectangular signal generating circuit configured to generate a plurality of rectangular signals different in pulse width, and a synthesizing circuit configured to synthesize the plurality of rectangular signals outputted from the rectangular signal generating circuit to generate the pulse signal with a duty ratio corresponding to the second data signal.
    Type: Grant
    Filed: January 31, 2008
    Date of Patent: July 13, 2010
    Assignees: Sanyo Electric Co., Ltd., Sanyo Semiconductor Co., Ltd.
    Inventors: Hiroaki Kawakami, Takashi Someya, Tetsuya Yoshitomi
  • Patent number: 7756402
    Abstract: An exemplary method for controlling rotation speed of a computer fan includes: judging the type of a fan by comparing two rotation speeds detected before and after changing a duty cycle of a PWM signal respectively; controlling the computer fan as a 4-pin fan the PWM signals if the rotation speeds are different; and controlling the computer fan as a 3-pin fan via voltage signals converted from the PWM signals if the rotation speeds are equal. And an exemplary circuit for controlling rotation speed of a computer fan is capable of controlling rotation speed of the 4-pin fan via PWM signals, and controlling rotation peed of the 3-pin fan via voltage signals converted from PWM signals.
    Type: Grant
    Filed: December 11, 2007
    Date of Patent: July 13, 2010
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Hua Zou, Feng-Long He, Wei Wang
  • Patent number: 7750596
    Abstract: The semiconductor device according to the present invention generates pulse width modulation signals for controlling inverter circuits that drive a motor. The semiconductor device includes: a first register which holds values for determining a period in which each pulse width modulation signal becomes active; a correction buffer which holds a correction value; a first counter; a second counter which counts a value obtained by temporally advancing or delaying a count value of the first counter; a selector which selects the count value of the first counter or the count value of the second counter; and a pulse width modulation control unit which generates each pulse width modulation signal, logical values of which are switched in a timing when the selected count value matches the value held by the first register.
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: July 6, 2010
    Assignee: Panasonic Corporation
    Inventors: Shigehiro Masamoto, Masaru Kohara
  • Patent number: RE42113
    Abstract: An integrated control and power driving system moves a read/write head carrying arm over the surface of a disk. The integrated control and power driving system is applicable to a spindle motor, a mass storage disk drive and a voice-coil motor, for example, and includes a first chip and a second chip. The first chip integrates the output power stages driving the motors, and has an interface for outputting feedback signals representing functioning conditions of the voice-coil motor and of the spindle motor, and for receiving digital control signals of the output power stages. The second chip integrates logic drive and control circuitries of the power stages and an interface for receiving the feedback signals output by the first chip, and for transmitting to the first chip the digital control signals.
    Type: Grant
    Filed: February 18, 2010
    Date of Patent: February 8, 2011
    Assignee: STMicroelectronics S.r.l.
    Inventors: Giuseppe Maiocchi, Michele Boscolo, Roberto Bardelli