Temperature Compensation Patents (Class 318/634)
  • Patent number: 11591009
    Abstract: Technical solutions are described for controlling operation of an electric machine such as a permanent magnet synchronous motor (PMSM) drive or motor control system to protect against excessive machine current or voltage in a PMSM drive. Systems and methods employ a torque control algorithm for PMSMs that uses the constraints of both machine current and voltage capability in PMSM drives, and online torque command modification according to the maximum allowed torque under these machine current and voltage constraints.
    Type: Grant
    Filed: November 25, 2019
    Date of Patent: February 28, 2023
    Assignee: Steering Solutions IP Holding Corporation
    Inventors: Haibo Li, Prerit Pramod, Krishna M P K Namburi, Zhe Zhang
  • Patent number: 11383374
    Abstract: The present disclosure relates to a pallet transfer system, including: a set-up structure that inserts a material into and withdraw a material out from a pallet; a pallet storage, on which the pallet is loaded; a material processing device that processes the material; a pallet transfer device that transfers the pallet to the set-up structure, the pallet storage, or the material processing device; a detector that detects a load applied to the pallet transfer device; and a controller that controls a speed of the pallet transfer device according to the information detected by the detector.
    Type: Grant
    Filed: October 7, 2015
    Date of Patent: July 12, 2022
    Assignee: DOOSAN MACHINE TOOLS CO., LTD.
    Inventor: Jae Doo Sim
  • Patent number: 10642508
    Abstract: Object data, such as a key-value pair, are stored in a disk drive in conjunction with metadata associated with the object data. A key-value pair and metadata associated therewith are written in different locations in the disk drive, but as part of a single sequential write operation, such as when contents of a key-value buffer containing one or more key-value pairs are flushed to the disk drive. The key-value pair may be written during a first phase of the sequential write operation and the metadata may be written during a second phase of the sequential write operation that does not immediately precede or follow the first phase.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: May 5, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Abhijeet Gole, Ratnadeep Joshi, Philip A. Kufeldt
  • Patent number: 10466907
    Abstract: In a data storage system, the available space of a magnetic storage device is divided into multiple sequential write regions for storing sequentially written data, where the regions are each separated from adjacent sequential write regions by a guard space. Object data, such as key-value pairs, are written sequentially to a particular sequential write region, in blocks of data that correspond to the contents of a nonvolatile buffer being flushed to the magnetic storage device. When a key-value pair stored in the magnetic storage device is subsequently updated, the original key-value pair is not overwritten. Instead, the new version of the key-value pair is included in the next block of data to be written to the magnetic storage device, and a mapping table tracks the location of the newest version of each key-value pair stored in the magnetic storage device.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: November 5, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Abhijeet Gole, Ratnadeep Joshi, Philip A. Kufeldt
  • Patent number: 10365634
    Abstract: To have a setting and adjusting function of setting and adjusting a control parameter that is set to one servo amplifier for a multiaxial control system that includes a plurality of axes, each of which is a combination of the servo amplifier with one servo motor, and that synchronizes and controls the axes according to a command from a motion controller, to group some of the axes, which constitute mechanical axes in which the axes are mechanically coupled, as one group, to perform adjustment of the control parameter on the axes that constitute the group, and to display an average value of adjustment results of a control parameter of all the axes that constitute the group as a control parameter value of the mechanical axes in each item of the control parameter.
    Type: Grant
    Filed: October 11, 2013
    Date of Patent: July 30, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventor: Takayuki Wakana
  • Patent number: 10270381
    Abstract: The present invention discloses an intelligent power control system for driving UAV motors comprising: a motor temperature reading unit, a processing unit and a motor power output controlling unit. The motor-temperature reading unit may be configured for reading a temperature of at least one motor mounted in the UAV. The processing unit may be configured for comparing whether the read temperature exceeds a first particular temperature, and controlling the motor power output controlling unit to adjust dynamically allowed maximum output power of various motors according to a comparison result. The present invention is also related to an intelligent power control system for driving UAV motors, and a UAV utilizing the intelligent power control system for driving UAV motors.
    Type: Grant
    Filed: April 14, 2017
    Date of Patent: April 23, 2019
    Assignee: SZ DJI TECHNOLOGY CO., LTD.
    Inventor: Ye Tao
  • Patent number: 10148215
    Abstract: A system of calculating temperature may include: a motor including a housing having opened ends, a cover connected to the housing to close at least one of the opened ends, a shaft rotatably disposed in the housing and having one end which penetrates through a center portion of the cover, a rotor fixed on an exterior circumference of the shaft in the housing and the cover, a stator fixed on an interior circumference of the housing, and an air gap formed between an exterior circumference of the rotor and an interior circumference of the stator; an input portion receiving a real time input and a predetermined input; and a control portion establishing a thermal equivalent circuit using the inputs of the input portion and convection or conduction characteristics between constituent elements of the motor, and calculating a temperature of each constituent element using the thermal equivalent circuit.
    Type: Grant
    Filed: October 13, 2017
    Date of Patent: December 4, 2018
    Assignees: Hyundai Motor Company, Kia Motors Corporation
    Inventors: YoungJin Shin, Sanghoon Moon, WoongChan Chae, Hyoungjun Cho, Jung Shik Kim
  • Patent number: 9575104
    Abstract: In an electrical machine which has unidirectional excitation applied to its windings, the mean values of voltage and current can be computed from the instantaneous phase voltage and current by the use of, for example, low-pass filters (in either the analogue or digital domain). The value of winding resistance can then be calculated by dividing the mean voltage by the mean current. This avoids the cost, fragility and potential inaccuracy of conventional temperature sensors, and provides the controller with an ongoing estimate of winding temperature.
    Type: Grant
    Filed: December 3, 2013
    Date of Patent: February 21, 2017
    Assignee: NIDEC SR DRIVES LTD.
    Inventor: Michael James Turner
  • Patent number: 9245540
    Abstract: An electrical circuit includes: a controlled switch; one or more temperature sensors in thermal contact with the controlled switch; and a control unit configured to: receive a temperature signal from the one or more temperature sensors; compare the received temperature signal to a predetermined threshold; and in response to the received temperature signal exceeding the predetermined threshold, render the controlled switch inoperative.
    Type: Grant
    Filed: October 29, 2014
    Date of Patent: January 26, 2016
    Assignee: Western Digital Technologies, Inc.
    Inventors: John R. Agness, William K. Laird
  • Publication number: 20150048772
    Abstract: A motor drive device in embodiments includes: a motor drive unit that generates a current for driving a motor on a basis of a position command and a position detection value of the motor; a motor-coil ambient-temperature estimation unit that calculates a motor-coil ambient-temperature estimation value by correcting an output value of a temperature sensor provided in a peripheral portion of a motor coil of the motor by using a filter including both a phase-lead characteristic and a low-pass characteristic; a motor-coil increased-temperature estimation unit 6 that calculates a motor-coil increased-temperature estimation value on a basis of the current; and a motor-coil protection unit 9 that limits the current on a basis of the motor-coil ambient-temperature estimation value and the motor-coil increased-temperature estimation value.
    Type: Application
    Filed: March 30, 2012
    Publication date: February 19, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Yuichi Nagata, Shuya Sano, Hiroshi Sugie
  • Patent number: 8866428
    Abstract: A method for determining a temperature of an electric motor including stator windings includes injecting an AC current into a D-axis current of a stator winding at a frequency that is synchronized with a control frequency of the electric motor, determining a DC-phase current, determining a resistance of the stator winding corresponding to the DC-phase current and an applied voltage, and determining a temperature of the electric motor as a function of the resistance of the stator winding.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: October 21, 2014
    Assignee: GM Global Technology Operations LLC
    Inventors: Lei Hao, Yilu Zhang, Siwei Cheng
  • Publication number: 20140210394
    Abstract: A method for operating an electric motor which is used as an electric servo drive in an electronic power steering system of a motor vehicle for power assistance and which has a number of magnetic elements and phase windings and is actuated and/or controlled by an electronic control unit of the electronic power steering system, wherein a temperature of at least one magnetic element of the electric motor is continuously determined during the operation of the electric motor by way of a temperature model and wherein, based on the temperature of the at least one magnetic element of the electric motor determined by way of the temperature model, an electrical current flowing in at least one of the phase windings of the electric motor is limited, taking into account a predeterminable limit temperature of the at least one magnetic element of the electric motor.
    Type: Application
    Filed: December 30, 2013
    Publication date: July 31, 2014
    Applicant: ZF LENKSYSTEME GMBH
    Inventors: Thomas Kuehnhoefer, Alexander Krautstrunk
  • Patent number: 8786244
    Abstract: Methodologies and systems are provided for current estimation in electric motor. The system comprises an electric motor having sensors for sensing at least motor current, motor temperature and motor speed. A vehicle controller is coupled to the sensors and includes a closed-loop current control system for the electric motor having a current compensation circuit for providing a current compensation signal that is used to adjust a current command for the electric motor. The current compensation circuit includes a short-circuit current calculator for providing a short-circuit current value based upon the motor temperature and the motor speed, a compensation gain calculator for providing a gain compensation value based upon the motor speed, and circuitry for combining the motor current, the short-circuit current value and the gain compensation value to provide the current compensation signal. Methods for current estimation in electric motor are also provided.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: July 22, 2014
    Assignee: GM Global Technology Operations LLC
    Inventor: Jihoon Jang
  • Patent number: 8786227
    Abstract: An electric compressor controller includes a compressor that compresses refrigerant of an air conditioning system; a motor that drives the compressor; an inverter that selectively control switching elements based on PWM pulse signals to supply drive power to the motor and heats the refrigerant by heat generated due to switching of the switching elements during a heating operation; temperature detectors each detects junction temperature of each of the switching elements; a drive controller that supplies the pulse signals to the inverter to control the inverter; and a slope varying unit that variably controls precipitous degree of rising/falling slope waveforms of the pulse signals based on the junction temperature detected by the temperature detectors. According to the electric compressor controller, efficiency for heating refrigerant is improved, so that its own heating ability is improved.
    Type: Grant
    Filed: June 9, 2011
    Date of Patent: July 22, 2014
    Assignee: Calsonic Kansei Corporation
    Inventor: Takashi Kubo
  • Patent number: 8704470
    Abstract: A first calculation unit subtracts third digital data which indicates the minimum value of the duty ratio from first digital data which indicates the duty ratio of the PWM driving operation. A slope calculation unit generates slope data which is dependent on the temperature based upon second digital data which indicates the temperature. A second calculation unit multiplies the slope data by the output data of the first calculation unit. A third calculation unit sums the output data of the second calculation unit and the third digital data. A selector receives the output data of the third calculation unit and the third digital data, selects one data that corresponds to the sign of the output data of the first calculation unit, and outputs the data thus selected as a duty ratio control signal.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: April 22, 2014
    Assignee: Rohm Co., Ltd.
    Inventors: Tatsuro Shimizu, Hiroyuki Ishii
  • Patent number: 8634976
    Abstract: A method for operating an electric motor is provided. The method includes receiving a torque request; determining long term torque capabilities and short term torque capabilities of the electric motor; generating a torque command based on the torque request and at least one of the long term torque capabilities or the short term torque capabilities; and controlling the electric motor in accordance with the torque command.
    Type: Grant
    Filed: March 1, 2010
    Date of Patent: January 21, 2014
    Assignee: GM Global Technology Operations LLC
    Inventors: Brian A. Welchko, Nitinkumar R. Patel, Leah Dunbar, William R. Cawthorne, Steven E. Schulz
  • Patent number: 8509611
    Abstract: A lens controlling device disclosed herein includes: a servo calculation section which calculates a motor current setting value such that a lens position detection signal which is inputted from a photo reflector agrees with a predetermined target lens position setting signal; a motor driver which generates a motor current in accordance with the motor current setting value, and supplies the motor current to a lens drive motor; and a temperature correction calculation section which monitors the motor current setting value to generate the temperature correction signal, and corrects either one of the target lens position setting signal and the lens position detection signal.
    Type: Grant
    Filed: November 3, 2011
    Date of Patent: August 13, 2013
    Assignee: Rohm Co., Ltd.
    Inventors: Koji Saito, Akihito Saito
  • Patent number: 8355828
    Abstract: A power model that relates the settings of resource actuators to power consumption levels of the resource actuators and a condition model that relates the settings of the resource actuators to an environmental condition at the location of the at least one entity and a power consumption level of the at least one entity are developed. A constraint optimization problem having an objective function and at least one constraint is formulated, where the objective function computes at least a proportional quantity of a total power consumption level of the resource actuators and the at least one constraint comprises a setpoint environmental condition at a location of the at least entity. A solution to the constraint optimization problem is determined, where the solution provides optimal values for the resource actuator settings.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: January 15, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Niraj Tolia, Zhikui Wang, Manish Marwah, Cullen E. Bash, Parthasarathy Ranganathan, Xiaoyun Zhu
  • Patent number: 8344675
    Abstract: A rechargeable electric power tool includes a motor driven by a secondary battery, a switching element for regulating power distribution to the motor, a motor control unit for controlling rotation of the motor through the switching element, a lead wire for supplying a drive current to the motor therethrough and a trigger switch changed over by a user for turning on or off the drive current supplied to the motor through the lead wire. In the rechargeable electric power tool, upon changeover of the trigger switch, a microcomputer determines a magnitude relation between a detected temperature outputted from a first thermistor and a first temperature threshold value. If the detected temperature is determined to be greater than the first temperature threshold value, the microcomputer is set in a limited operation mode in which a revolution number of the motor is limited to a predetermined value or less.
    Type: Grant
    Filed: November 10, 2009
    Date of Patent: January 1, 2013
    Assignee: Panasonic Electric Works Power Tools Co., Ltd
    Inventors: Tatsuya Miwa, Atsumasa Kubota, Masaki Ikeda, Kazuhiko Nishii
  • Patent number: 8278864
    Abstract: The invention relates to improvements in compressors and, in particular, to an improvement in a method of controlling variable speed dynamic compressors to avoid ‘motor overload as a result of choking.1 The invention therefore comprises a method of controlling a compressor to provide compressed gas at a target delivery pressure (Pt) and prevent excessive motor power consumption, the compressor being driven by a variable speed motor which has motor windings, wherein the gas inlet temperature (Tin), gas output delivery pressure (Pd), motor speed (Vm) and the motor winding temperature (Tmw) are continuously measured during operation of the compressor. The gas inlet temperature (Tin) is used to determine a predetermined maximum motor winding temperature (Tmwmax) limit. The maximum motor winding temperature (Tmwmax) is used (to set a maximum motor speed (Vmmax) limit.
    Type: Grant
    Filed: August 7, 2008
    Date of Patent: October 2, 2012
    Assignee: Gardner Denver Deutschland GmbH
    Inventor: Geoffrey George Powell
  • Publication number: 20120180592
    Abstract: An electrical machine apparatus includes an electromagnetic coil, a rotor magnet, n (n is an integer not less than 2) magnetic sensors to detect an electric angle of the rotor magnet, and a position detection part to detect a position of the rotor magnet by using outputs of the magnetic sensors. Each of the magnetic sensors generates a sensor output signal having a curved line waveform and a period of electric angle 2? of the electrical machine apparatus. The respective n magnetic sensors are arranged to generate the sensor output signals with a phase difference other than an integer times ? in electric angle. The position detection part calculates a movement amount of the rotor magnet from a starting point as a position before movement by using the sensor output signals of the n magnetic sensors.
    Type: Application
    Filed: January 18, 2012
    Publication date: July 19, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Kesatoshi TAKEUCHI
  • Patent number: 8203300
    Abstract: A method of closed-loop controlling determines a first feedback variable by sampling a control variable and a second feedback variable by averaging the control variable, compares the first and second feedback variables with a command variable, and sets the control variable on the basis of the comparing result so that the control variable follows a command variable.
    Type: Grant
    Filed: January 11, 2010
    Date of Patent: June 19, 2012
    Assignee: Beckhoff Automation GmbH
    Inventor: Jens Onno Krah
  • Patent number: 8084982
    Abstract: An HVAC actuator, such as a spring return actuator, may adjust the maximum output torque of the motor with the varying spring return force of the HVAC actuator as the HVAC actuator moves through its range of motion. In some cases, this may provide a more constant force at the output of the HVAC actuator and reduce the force that is applied through the motor, drive train and/or the HVAC component when an end stop is reached. Also, an HVAC actuator is disclosed that can be configured to discover and store the location of one or more end stop(s), and to slow the speed of the motor down before the end stop(s) is reached. This may reduce the force that is applied through the motor, drive train and/or the HVAC component when an end stop is reached.
    Type: Grant
    Filed: November 18, 2008
    Date of Patent: December 27, 2011
    Assignee: Honeywell International Inc.
    Inventors: Cory Grabinger, Nathan Carlson, Ivo Chromy, David Cermak
  • Patent number: 8013560
    Abstract: The non-linear elastic deformation component included in the angular transmission error of an actuator provided with a wave gear drive is a component of the angular transmission error occurring due to elastic deformation of a flexible externally-toothed gear when the direction of rotation of the motor shaft changes. This component can be analyzed by driving the motor in a sine-wave shape. A model of the non-linear elastic deformation component (non-linear model) obtained from the analysis results is used to store data or a function for compensating for this component in a motor-control device. Compensation for the non-linear elastic deformation component (?Hys) is added to a motor-shaft angle command (?*M) as a compensation input (N?*TE) for feed-forward compensation. As a result, the non-linear elastic deformation component (?Hys) can be effectively reduced, and the positioning precision of the actuator can be improved.
    Type: Grant
    Filed: January 13, 2009
    Date of Patent: September 6, 2011
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Kozo Sasaki, Yoshifumi Okitsu, Toshio Yajima, Makoto Iwasaki
  • Patent number: 7987024
    Abstract: A method for controlling fan speed includes providing a fan that is in fluid communication with at least one heat producing component, detecting a temperature, determining a fan speed using the detected temperature and a nonlinear fan speed function, and applying a control signal to the fan such that the fan operates at the determined fan speed in order to cool the at least one heat producing component.
    Type: Grant
    Filed: October 3, 2008
    Date of Patent: July 26, 2011
    Assignee: Dell Products L.P.
    Inventors: Eric Tunks, Tyler Duncan
  • Patent number: 7949233
    Abstract: A method for controlling a heat-dissipating fan for an electronic component includes the steps of: detecting a temperature of the electronic component, and outputting a first control signal corresponding to the temperature thus detected; receiving a load current of the electronic component, and converting the load current into a second control signal; and controlling a rotating speed of the heat-dissipating fan with reference to the first control signal and the second control signal. A device employing the method includes a current detecting module adapted for detecting a load current, a temperature control circuit adapted for detecting a temperature, and a logic circuit unit coupled to the current detecting module and the temperature control circuit and controlling a rotating speed of a heat-dissipating fan.
    Type: Grant
    Filed: April 3, 2008
    Date of Patent: May 24, 2011
    Assignee: Acer Incorporated
    Inventors: Yi-Tung Chiang, I-Huei Huang, Nien-Yu Liao
  • Patent number: 7888903
    Abstract: Provided is an apparatus and method for estimating sensor signals to stabilize a posture of a mobile satellite tracking antenna.
    Type: Grant
    Filed: November 9, 2006
    Date of Patent: February 15, 2011
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seong-Ho Son, Soon-Young Eom, Young-Bae Jung, Jae-Seung Yun, Soon-Ik Jeon
  • Publication number: 20110031924
    Abstract: A shape memory alloy driver comprises a displacement detection portion, a drive control portion, and a compensation calculation portion. The displacement detection portion detects displacement of a shape memory alloy based on a resistance value etc. detected from the shape memory alloy. The drive control portion applies a voltage or current to the shape memory alloy by servo control to thereby displace the shape memory alloy to a target displacement value fed from a microcomputer etc. The compensation calculation portion calculates a compensated displacement value from the detected displacement value and a variation—attributable to the environment temperature—of the drive control value which the drive control portion uses for controlling the voltage or current. Having been fed with the compensated displacement value, the drive control portion varies the drive control value such that the compensated displacement value is equal to the target displacement value.
    Type: Application
    Filed: October 21, 2010
    Publication date: February 10, 2011
    Applicant: Konica Minolta Opto, Inc.
    Inventor: Yasuhiro HONDA
  • Patent number: 7781991
    Abstract: A heat dissipation system used in an electronic device includes a plurality of fans positioned in the electronic device, a sensing module, and a processing module. The sensing module is configured for detecting temperature, relative humidity, and air pressure of airflow flowing in the electronic device. The processing module is configured for adjusting a voltage applied to each of the plurality of fans according to the detected temperature, relative humidity, and air pressure of the airflow.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: August 24, 2010
    Assignee: Hon Hai Precision Industry Co., Ltd.
    Inventors: Yu-Shan Chou, Po-Lin Wang, Ching-Te Chu
  • Publication number: 20100194328
    Abstract: A system for maintaining thermal stability of a motion stage driven by a motor comprises a motion current generator operative to produce a motion current to drive the motion stage to move and a thermal current generator operative to produce a thermal current to dissipate heat in the motion stage for controlling a temperature of the motion stage without producing corresponding movement of the motion stage. A summation controller is operative to combine the motion current with the thermal current, and to produce a combined current output to the motor.
    Type: Application
    Filed: February 5, 2009
    Publication date: August 5, 2010
    Inventors: Gary Peter WIDDOWSON, Wai Chuen Gan, Cheuk Wah Tang, Chor Fai Wong
  • Patent number: 7612521
    Abstract: In a fan motor drive circuit which drives a motor based on a pulse-modulated external control signal, a temperature control signal generator generates a pulse-modulated temperature control signal whose duty ratio changes depending on temperature. A signal synthesizer synthesizes the external control signal and the temperature control signal by a logical operation. A drive controller drives the motor based on output of the signal synthesizer.
    Type: Grant
    Filed: December 9, 2005
    Date of Patent: November 3, 2009
    Assignee: Rohm Co., Ltd.
    Inventor: Satoshi Miyajima
  • Patent number: 7583043
    Abstract: An apparatus, system, and method are disclosed for controlling fan speed. A power sensing module senses input voltage and current of a power supply. The power supply includes one or more stages and regulates at least one output bus. A power calculation module calculates input power from the input voltage and the input current. A temperature sensing module senses an ambient temperature and/or a temperature at a component cooled by a fan. A fan speed calculation module calculates a fan speed signal for the fan. The fan speed signal is a function of the input power calculated by the power calculation module and the sensed temperature sensed by the temperature sensing module for at least a portion of a fan speed range. A fan speed transmission module transmits the fan speed signal to the fan and adjusts a fan speed based on the fan speed signal.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: September 1, 2009
    Assignee: International Business Machines Corporation
    Inventors: Chu Te Chung, C. Charles Dishman, Jen-Ching Lin, Eino A. Lindfors
  • Patent number: 7583041
    Abstract: The present invention includes temperature transition estimating means 24, 25 for estimating a temperature transition of an electric motor 1 caused by the passage of electric current through the electric motor 1, an electric pump 8 as coolant supplying means for supplying a coolant to the electric motor, and coolant supply control means 26 to 28 for controlling the pump 8 according to the temperature transition of the electric motor 1 and the coolant temperature. The amount of operation of the electric pump 8 is determined from the temperature transition and the coolant temperature. This structure makes it possible to prevent overheating of the electric motor properly using the coolant while minimizing the energy consumption involved in using the coolant.
    Type: Grant
    Filed: October 7, 2005
    Date of Patent: September 1, 2009
    Assignee: Honda Motor Co., Ltd.
    Inventors: Noritaka Yamaguchi, Yutaka Tamagawa
  • Patent number: 7573220
    Abstract: A self-calibrating, continuous variable speed fan for use in cooling electronic circuitry is disclosed. Upon initial power-up, in an environment of known temperature, the self-calibrating fan accommodates for the tolerances of its electronic components by reading a voltage from its thermistor array and comparing the actual value to an expected value for the given temperature. The difference is then stored in the non-volatile memory of a microcontroller for use in adjusting future voltage readings from the thermistor array. During normal operation, adjusted readings from the thermistor array are then converted by the microcontroller into a control signal for driving the motor of a cooling fan. A quickly cycling stochastic process between adjustments to fan motor speed and temperature readings is then established, thereby maintaining a high degree of control over the device to be cooled.
    Type: Grant
    Filed: March 6, 2007
    Date of Patent: August 11, 2009
    Assignee: Minebea Co., Ltd.
    Inventors: Eric A. Hardt, Scott Frankel
  • Patent number: 7538508
    Abstract: A thermal overload protection for an electrical device, particularly an electric motor (M), measures a load current supplied to the electrical device (M), and calculates the thermal load on the electrical device on the basis of the measured load current, and shuts off (S2) a current supply (L1, L2, L3) when the thermal load reaches a given threshold level. The protection comprises a processor system employing X-bit, preferably X=32, fixed-point arithmetic, wherein the thermal load is calculated by a mathematic equation programmed into the microprocessor system structured such that a result or a provisional result never exceeds the X-bit value.
    Type: Grant
    Filed: February 1, 2005
    Date of Patent: May 26, 2009
    Assignee: ABB Oy
    Inventors: Janne Kuivalainen, Peter Österback
  • Publication number: 20090091284
    Abstract: A P-range side delimiting position of a movable range of a range change mechanism is learned by rotating a motor to a corresponding rotational position, which corresponds to the P-range side delimiting position. A climb correction amount is set for a learning value of the P-range side delimiting position to correct the learning value of the P-range side delimiting position in view of presence of a relatively small angle of rotation of the motor beyond the corresponding rotational position, which corresponds to the P-range side delimiting position. The climb correction amount is set according to motor temperature information, which is one of a temperature of the motor and a temperature that relates to the temperature of the motor.
    Type: Application
    Filed: October 3, 2008
    Publication date: April 9, 2009
    Applicant: DENSO CORPORATION
    Inventors: Eiji Isobe, Shigeru Kamio
  • Publication number: 20080303475
    Abstract: Methods and systems are provided for controlling permanent magnet machines. The method includes determining a maximum torque of the PM machine based on an error between a commanded d-axis flux and an estimated d-axis flux of the PM machine, and adjusting a torque command based on the maximum torque. The error associated with a variation between a current temperature and a nominal temperature of the PM machine.
    Type: Application
    Filed: June 7, 2007
    Publication date: December 11, 2008
    Inventors: Nitinkumar R. Patel, Brian A. Welchko, Bonho Bae, Steven E. Schulz
  • Publication number: 20080265813
    Abstract: A dynamic braking load analyzer that determines the proper resistance value for a dynamic braking load resistor to be used in combination with a variable frequency drive or servo-drive to accommodate the power dissipated from an induction motor when it is being reduced in speed. The analyzer includes a resistor bank having a plurality of resistors electrically coupled in parallel. Switches are provided between the resistors, and a resistor selector switch determines which resistors are switched into the resistor bank circuit. A heat sensing resistor in the resistor bank measures the heat generated by the resistors and provides a signal that is read by a heat meter. The combination of the temperature measurement and the resistance of the resistors in the circuit gives the proper braking resistance value for the deceleration of the induction motor.
    Type: Application
    Filed: April 30, 2008
    Publication date: October 30, 2008
    Applicant: Powerohm Resistors, Inc
    Inventors: Joseph S. Eschleman, Thomas Yingling, Michael Crowe
  • Publication number: 20080224647
    Abstract: Kinematic control of an electronic positioner and its associated actuator is effected through a control algorithm that delivers energy to the actuator based on observed motion produced by a previous delivery of energy. The algorithm achieves control based on a desired or user-specified resolution. Electronic braking between energy delivery intervals improves the speed at which the desired position is achieved. Temperature of the force producing mechanism is determined, as by monitoring energy consumed, and used to control how power is delivered to the actuator.
    Type: Application
    Filed: March 24, 2008
    Publication date: September 18, 2008
    Applicant: PEAKTRONICS, INC.
    Inventors: Peter W. Mueller, Jack M. Leason
  • Publication number: 20080144341
    Abstract: A switch-type power converter includes a double FET switch operating in a variable duty cycle mode under the control of a Unitrode 3846 integrated circuit controller. Indications of excess input voltage and reverse battery connections are provided by circuits including an element which permanently changes state. A cooling fan mounted on a finned heat sink is operated in a variable speed mode.
    Type: Application
    Filed: January 14, 2008
    Publication date: June 19, 2008
    Applicant: Progressive Dynamics, Inc.
    Inventor: James C. Cook
  • Publication number: 20080054835
    Abstract: An apparatus is provided for controlling drive of a motor mounted on a vehicle and formed to have a rotor and a stator equipped with a plurality of phases of coils to be supplied by current in turn, phase by phase, to rotate the rotor. The apparatus comprises a voltage detector, temperature detector, setting block, and current-supply block. Of these, the voltage detector detects a voltage of power to be applied to the motor, while the temperature detector detects a temperature of the motor. The setting block uses the detected temperature and the detected voltage of the power to set a target torque at which the motor should generate a torque. The current-supply block supplies current to the motor so that the motor generates the torque on the target torque set by the setting block.
    Type: Application
    Filed: September 4, 2007
    Publication date: March 6, 2008
    Applicant: DENSO CORPORATION
    Inventor: Takuya Tamaru
  • Patent number: 7291995
    Abstract: An air fan rotation speed control method and a structure thereof aim to provide an automatic control mode and a manual control mode at the same time to control rotation speed regulation of an air fan to achieve instant heat dissipation for an environment and reduce temperature rising of the environment efficiently. The present invention has a rotation speed determination mechanism that adopts the higher rotation speed request at a higher priority to regulate the rotation speed of the air fan in either control mode. Hence the temperature of the environment can be reduced at the higher rotation speed.
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: November 6, 2007
    Assignee: Zippy Technology Corp.
    Inventor: Tsung-Chun Chen
  • Patent number: 7202624
    Abstract: A self-calibrating, continuous variable speed fan for use in cooling electronic circuitry is disclosed. Upon initial power-up, in an environment of known temperature, the self-calibrating fan accommodates for the tolerances of its electronic components by reading a voltage from its thermistor array and comparing the actual value to an expected value for the given temperature. The difference is then stored in the non-volatile memory of a microcontroller for use in adjusting future voltage readings from the thermistor array. During normal operation, adjusted readings from the thermistor array are then converted by the microcontroller into a control signal for driving the motor of a cooling fan. A quickly cycling stochastic process between adjustments to fan motor speed and temperature readings is then established, thereby maintaining a high degree of control over the device to be cooled.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: April 10, 2007
    Assignee: Minebea Co., Ltd.
    Inventors: Eric Hardt, Scott Frankel
  • Patent number: 7166978
    Abstract: An electric motor system includes an electric motor, a temperature sensor mounted therein capable of measuring a local temperature and generating a temperature related signal, and a processor configured to calculate an actual temperature of a rotor magnet from the temperature related signal, and an actual output torque from the actual rotor magnet temperature. A method for determining the actual output torque of a motor includes sensing a temperature within the motor, calculating a rotor magnet temperature from the sensed temperature, and calculating the actual output mechanical torciue from the rotor magnet temperature.
    Type: Grant
    Filed: June 6, 2005
    Date of Patent: January 23, 2007
    Assignee: Kendro Laboratory Products, LP
    Inventors: David M. Carson, Richard Hall
  • Patent number: 7109680
    Abstract: An object is to provide an inverter device capable of realizing exact protection of the winding of a motor. An inverter device for generating a pseudo alternating current by switching a direct current to drive a motor, comprises a controller that executes vector control on the basis of a secondary current applied to the motor. The controller calculates a current density from the secondary current to execute a predetermined protection operation on the basis of the calculated current density. The controller imposes a restriction on the operation frequency of the motor on the basis of the current density.
    Type: Grant
    Filed: February 2, 2005
    Date of Patent: September 19, 2006
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Mamoru Kubo, Kenji Nojima
  • Patent number: 7029239
    Abstract: A system may include a PWM generator and control logic. The PWM generator is configured to generate a PWM signal having a duty cycle dependent on a duty cycle value generated by the control logic. The control logic is configured to generate the duty cycle value to have a piecewise linear relationship with temperature such that at least two of a plurality of linear segments defined by the piecewise linear relationship have different slopes. In some embodiments, the piecewise linear relationship may be continuous.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: April 18, 2006
    Assignee: Standard Microsystems Corporation
    Inventors: Eileen M. Marando, Robert W. Schoepflin
  • Patent number: 6979971
    Abstract: An operation command for constructing compensation data is generated in a control device, and measurement data obtained from an external length measuring device is input to an input unit. The measurement data is compared with an estimated position in a control device of a cylinder servo motor, and errors between them is stored in a compensation memory. In addition, in normal operation, the external length measuring device is removed. A movement command is input to the input unit and compensated using the error stored in the compensation memory, so that the estimated error is deleted in the normal operation.
    Type: Grant
    Filed: April 26, 2001
    Date of Patent: December 27, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kouichi Takamune, Hidenobu Itou, Takao Mizutani
  • Publication number: 20040227485
    Abstract: A magnetic flux produced by the current of a motor is detected by means of a Hall element, and an infinitesimal current proportional to the actual current of the motor is outputted. The outputted infinitesimal current is run through a resistor, and a potential difference across the resistor is detected by a &Dgr;&Sgr; modulator circuit. The motor is subjected to feedback control based on the potential difference detected by the &Dgr;&Sgr; modulator circuit.
    Type: Application
    Filed: June 17, 2003
    Publication date: November 18, 2004
    Applicant: FANUC LTD
    Inventors: Shunsuke Matsubara, Shinichi Kono, Shinichi Horikoshi
  • Patent number: 6791785
    Abstract: A controller for a disk drive that accesses a look up table having a plurality of thermally characterized values corresponding to a plurality of seek operations. For each seek operation, the corresponding value is added to a register. The controller decrements the register at a rate that is determined using servo interrupts occurring as a result of the rotation of the disk. When the value of the register exceeds a threshold, the controller adjusts the subsequent seek operation so as to inhibit damage to the voice coil as a result of overheating.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: September 14, 2004
    Assignee: Western Digital Technologies, Inc.
    Inventors: Carl R. Messenger, David D. Nguyen
  • Publication number: 20040113580
    Abstract: A machine for machining a workpiece with at least one revolving or rotating tool has a work spindle with a shaft (5), whose temperature is monitored by means of at least one temperature sensor (26). The temperature sensor is detected in contactless fashion. The sensor (26) is preferably a radiation-sensitive sensor, which detects the temperature radiation output by the shaft (5). In triggering the positioning drive mechanisms, the control unit (35) of the machine (1) takes into account the temperature expansions of the shaft (5) that result from the temperature changes in the shaft. The positioning drive mechanisms serve to position a tool (6), carried by the shaft (5), relative to the workpiece (2). A machining precision is thus achieved that is independent of the temperature and temperature changes of the machine (1) overall, of temperature changes in the coolant-lubricant, and of temperature changes in the tool (6) and the shaft (5), that can all be caused by the power converted at the machining site.
    Type: Application
    Filed: December 3, 2003
    Publication date: June 17, 2004
    Inventor: Thomas Engelfried