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| Number | Title | Issue Date |
| 7619385 | Motor controller, washing machine, air conditioner and electric oil pump A motor controller capable of suppressing a large speed change generated at the time of changeover from a synchronous operation mode to a position feedback operation mode and implementing even acceleration characteristics regardless of the load torque by estimating ... | 11/17/2009 |
| 7352151 | Method of estimating magnetic pole position in motor and apparatus of controlling the motor based on the estimated position A magnetic pole position in a synchronous motor having salient poles is estimated from an instructed voltage applied to the motor, a current generated from the instructed voltage and parameters. To estimate the position substantially matching with a true magnetic po... | 04/01/2008 |
| 7348684 | Drive unit A drive unit is provided including a synchronous machine, a pulse counter unit for detecting a rotor position during the running operation of the synchronous machine, and a control unit. The control unit is constructed such that, with the start of the operation of t... | 03/25/2008 |
| 7312594 | Control system for synchronous machine A control system for a synchronous machine including a converter for converting DC voltage to AC voltage or AC voltage to DC voltage. The synchronous machine is driven by the converter. The control system further includes a magnetic pole position presuming device fo... | 12/25/2007 |
| 7292002 | Control method for twin synchronization In a control method for a twin synchronization in which two motors for driving two axes (moving elements 3) mechanically fastened to each other by a fastening part (a fastening jig 6) are synchronously operated, one of the two axes is operated at low s... | 11/06/2007 |
| 7274162 | Motor spindle control system and method In a motor having a number of poles that have nominally equiangularly-spaced positions that in fact deviate from those positions, the actual pole positions are determined by measuring the periods between zero-crossings of the back-EMF generated during pole-pair inte... | 09/25/2007 |
| 7245104 | Position-sensorless motor control device A position-sensorless motor control device has a superposer that superposes, on the drive current with which the motor is driven, a superposed current having a different frequency than the drive current, a superposed component extractor that extracts, from the motor... | 07/17/2007 |
| 7239108 | Method for stepper motor position referencing A method for referencing a polyphase stepper motor by monitoring the current step response in at least one driven phase is presented. The coil current step response is compared to past step responses in order to determine when an increase in or maximum load is prese... | 07/03/2007 |
| 7235939 | Method for detecting the angular position of a rotor in a brushless electric motor A method for detecting the angular position of a rotor in a brushless electric motor, of the type in which the emission of a polarity signal of the back electromotive force by a detection circuitry associated with the motor, includes the using a bi-directional count... | 06/26/2007 |
| 7191608 | Cooling apparatus There is provided a cooling apparatus which can prevent an abnormal increase in pressure of a high side at the time of starting. The cooling apparatus comprises: a refrigerant circuit which uses carbon dioxide as a refrigerant; and a control device which controls a ... | 03/20/2007 |
| 7180262 | Control system and method for electric drives with a.c. motors A vector-control system and method of a “sensorless” type for electric drives with a.c. motors is based upon generation of an oscillating magnetic field and upon measurement of the deviation, with respect to said oscillating field, of the flux generated thereby ... | 02/20/2007 |
| 7149606 | Synchronizing controllers linked by a communications network A control system includes controllers that are coupled mutually by a communications network, on which information, transmitted from a master controller to a slave controller, is used to make timing corrections on the slave controller in order to synchronize event ti... | 12/12/2006 |
| 7116067 | Power converter controlling apparatus and method providing ride through capability during power interruption in a motor drive system A method of controlling a power converter (20) of a motor drive system (10)controls the power converter (20) during a first operating mode by applying a current control scheme, which sets power converter commands to control torque current flowin... | 10/03/2006 |
| 7084597 | Motor control apparatus In an automatic transmission position control by a motor, it is determined whether the present instant belongs to a starting period, that is, the present instant is immediately after resetting of a control unit or application of power to it. If it is the starting pe... | 08/01/2006 |
| 7075265 | High phase order electrical rotating machine with distributed windings A rotating induction machine, containing five or more different phases, having windings distributed according to a sinc function with a cutoff frequency allowing low-order spatial harmonics but preventing higher order spatial harmonics from flowing. In a preferred e... | 07/11/2006 |
| 7067997 | Method for determining rotor position angle of synchronous machine A method for determining a rotor position angle of a synchronous machine, the method comprising the steps of determining inductances (LA, LB, LC) of the synchronous machine in stator phase directions; generating an inductance vector (L) on the basis of the determine... | 06/27/2006 |
| 7023170 | Origin offset calculation method of rotational position detecting device of electric motor and motor control device using the calculation method An inverter that executes a d q-axis control of a three-phase synchronous motor needs a rotational position sensor that detects rotational positions of an electric motor for mutual conversion between two-phase and three-phase. An angle error of this rotational posit... | 04/04/2006 |
| 7015671 | Circuit for operating an electric motor A circuit configuration for operating an electric motor is described, the circuit configuration containing a timer. As a function of a first differential signal between a setpoint signal and an actual value signal, a regulator supplies a first switch signal for feed... | 03/21/2006 |
| 6979975 | Rotation state detecting apparatus of a synchronous machine In a conventional rotation state detecting apparatus of a synchronous machine, since short-circuiting must be carried out twice or more when a rotation speed is detected, there have been problems in that it takes a time to detect a rotation state, and it takes a tim... | 12/27/2005 |
| 6956342 | Driving circuit for a DC brushless fan motor The present invention is a driving circuit for a DC brushless fan motor, comprising a control unit, a motor, a Hall element, a signal output unit, a temperature control circuit, a reverse protection circuit and a counter-electromotive force (CEMF) removal circuit, a... | 10/18/2005 |
| 6940250 | Synchronous motor control device and method of correcting deviation in rotational position of synchronous motor In a synchronous motor control device that corrects a deviation in rotational position which is related to a rotational position detector for a synchronous motor on which vector-control is performed, the synchronous motor control device includes: a current instructi... | 09/06/2005 |
| 6940239 | Motor driving device and motor driving method In a PWM-controlled motor driving device, a phase current is prevented from undergoing an abrupt transition at phase current switching points, thereby reducing vibrations and noise of the motor. A PWM control section produces two independent PWM control pulse signal... | 09/06/2005 |
| 6911742 | Method and apparatus for turbine/alternator on common shaft during start-up An electrical system for a turbine/alternator comprising a gas driven turbine and a permanent magnet alternator rotating on a common shaft includes an inverter circuit connectable either to an output circuit or the stator winding of the alternator. A control circuit... | 06/28/2005 |
| 6909263 | Gas turbine engine starter-generator exciter starting system and method including a capacitance circuit element A rotating electrical machine, such as an aircraft starter-generator, that includes an exciter that has its stator windings supplied with electrical power from a power supply. One or more switches are electrically coupled between the exciter stator winding and the p... | 06/21/2005 |
| 6838842 | Method for operating a brushless direct current motor A brushless, synchronous direct current motor is operated by supplying a direct current voltage as an input voltage for commutating the motor phase windings. The speed of the synchronous motor is modified or varied in two speed ranges. In the first speed range, a li... | 01/04/2005 |
| 6801011 | Magnetic pole position estimating method and control apparatus for synchronous motor The invention has an object to provide a magnetic pole position estimating method and a control apparatus for a synchronous motor which reliably detect the position of a magnetic pole of the synchronous motor to carry out stable control also when a high load is appl... | 10/05/2004 |
| 6788021 | Control method for switched reluctance motor A control algorithm provides automatic control of the turn-on angle used to excite the switched-reluctance motor (SRM). The control algorithm determines the turn-on angle that supports the most efficient operation of the motor drive system, and consists of two piece... | 09/07/2004 |
| 6777898 | Methods and apparatus for maintaining synchronization of a polyphase motor during power interruptions Methods and apparatus permit: monitoring a level of a DC source that is used to provide an operating DC voltage to a control circuit and to provide DC bus voltage to a driver circuit for a polyphase motor, the control circuit being of a type that senses signals in w... | 08/17/2004 |
| 6774599 | Servo actuator and position sensor In an actuator having an integrated drive circuit, a switching current flowing in a coil within the actuator is included in a position sensor signal of the actuator. According to the present invention, by arranging a detection circuit which performs sampling in sync... | 08/10/2004 |
| 6741059 | Controller for a wound rotor slip ring induction machine The direct torque control (DTC) principle is used to control the torque of a wound ring rotor slip induction machine, also known as a doubly fed or cascade machine, by utilizing a solid state inverter on the rotor side. In addition, the DTC principle is used to cont... | 05/25/2004 |
| 6703807 | Method and apparatus for controlling starting of synchronous motor and electric pump for controlling working fluid of motor vehicle driving system using the apparatus A method for controlling starting of a synchronous motor having an excellent starting ability and capable of coming into a commutation mode in a short time is provided. An AC current having a predetermined frequency is supplied to a field coil 81 of a syn... | 03/09/2004 |
| 6650084 | Motor driver A motor driver generates a signal synchronized with the rotation of a three-phase by comparing each of induction voltages generated in the motor's coils with a specified standard voltage. A triangular wave signal is generated such that its frequency incre... | 11/18/2003 |
| 6573672 | Fail passive servo controller The present invention provides apparatus, systems and methods for fail passive servo controllers. In accordance with an exemplary embodiment of the present invention, servo controller is used with an ALS to control an aircraft during landing procedures. I... | 06/03/2003 |
| 6483270 | Method and device for controlling position sensorless motor The present invention relates to a control method and a control device for a position sensorless motor which has position sensorless operation and synchronized operation, wherein a rotation position of a rotor is detected on the basis of counter electromo... | 11/19/2002 |
| 6448735 | Controller for a wound rotor slip ring induction machine The direct torque control (DTC) principle is used to control the torque of a wound ring rotor slip induction machine, also known as a doubly fed or cascade machine, by utilizing a solid state inverter on the rotor side. In addition, the DTC principle is u... | 09/10/2002 |
| 6404161 | Self-calibrated circuit for the measurement of time intervals A circuit for the measurement of time intervals includes a generator providing primary periodic pulses, a frequency divider capable of transmitting secondary periodic pulses for scaling down the frequency of the primary periodic pulses, and a counter for ... | 06/11/2002 |
| 6392905 | Method and circuit for reducing battery ripple current in a multiple inverter system of an electrical machine A pulse width modulation circuit (10) has a first set of windings with a first inverter circuit coupled thereto and a second set of windings having a second inverter circuit coupled thereto. A pulse width modulation controller pulse width modulates the fi... | 05/21/2002 |
| 6392378 | Method for operating and controlling hysteresis motors In a method of operating and controlling hysteresis motors energized by a three-phase power supply and individually monitored by an operating monitoring system, whereby the effective power output of the individual motors is determined and the three-phase ... | 05/21/2002 |
| 6388416 | Motor control device and motor control method A motor current detection amplifier detects a motor current's areas in two phase periods with reference to a motor voltage. A controlling microcomputer computed the ratio of the motor current areas of the two phase periods and provides the same as phase d... | 05/14/2002 |
| 6362590 | Starting of synchronous machine without rotor position or speed measurement A system for starting synchronous motor from a pulse-width-modulated static inverter without using rotor position or speed measurements. The system monitors supply current to the stator and derives a relationship between that current and the magnetizing f... | 03/26/2002 |
