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| Number | Title | Issue Date |
| 8183813 | Power supply arrangement The invention relates to a frequency converter, which is fitted to supply power between a polyphase alternating electricity source and an electric machine. The frequency converter comprises a network rectifier connected to the alternating electricity source and an i... | 05/22/2012 |
| 8134323 | Bypass and synchronous transfer arrangement for a medium voltage drive control system A medium voltage variable frequency drive having a 2-high controller configuration with a dual bus system is described. The drive control system includes at least one motor control cabinet housing a fused medium voltage bypass controller, a non-fused transfer contro... | 03/13/2012 |
| 8054019 | Method and apparatus for controlling a motor The invention concerns a method and an apparatus for controlling a three-or-more-phase motor driven by a frequency converter. In the method, a change-over switch of the frequency converter is controlled to a continuously conducting state and at the same time the pha... | 11/08/2011 |
| 8049445 | Motor controller A motor controller that outputs a drive signal to a direct-current motor to drive the motor is provided. The motor controller includes a drive circuit that generates the drive signal. The drive circuit superimposes on a direct-current voltage an alternating-current ... | 11/01/2011 |
| 7791302 | Method for measuring a motor current The invention relates to a method for measuring a current that flows through a motor, in which a power switch that supplies the motor with electric energy is controlled by a control unit via a pulse width-modulation signal. The pulse width-modulation signal comprise... | 09/07/2010 |
| 7319299 | Determining types of cooling fans used in a personal computer thereby using optimum parameters to control each unique cooling fan A cooling fan, system and method for controlling cooling fans in a personal computer. A unique series of sensing points is placed on a rotating hub of a cooling fan in order to uniquely identify the particular type of cooling fan. A tachometer sensor mounted in the ... | 01/15/2008 |
| 7176653 | Electric motor drive The invention relates to an electric motor drive for operating an alternating-current motor. The electric motor drive comprises a frequency converter for controlling the motor, which frequency converter comprises a rectifier and an inverter implemented using semicon... | 02/13/2007 |
| 7154239 | Controller for a brushless direct current motor A controller includes a power source unit, a drive circuit, and a state control circuit. The drive circuit is coupled to the power source unit, and includes a drive coil and a switching transistor unit. The switching transistor unit is operable in one of a circuit-m... | 12/26/2006 |
| 7126297 | Controlling method of a motor state A controlling method of a motor state described herein detects the motor operation in a regeneration state or a motor state. The output frequency value of an AC motor drive is calculated and adjusted to stabilize the voltage of a DC bus such that over-voltage protec... | 10/24/2006 |
| 7112937 | Device and method for driving a motor A motor control device having memory for storing data indicative of a control mode and a pulse width modulation (PWM) value and logic that applies the pulse width modulation value to a voltage provided to a motor if the data indicative of the control mode indicates ... | 09/26/2006 |
| 7106024 | Filter with increased first harmonic response and reduced phase shift in a wide frequency band for encoderless drive applications A method and apparatus for use with a controller that supplies voltages to an induction machine via supply lines, the voltages including a fundamental voltage component and an injected voltage component, the line voltages also including harmonic voltage components w... | 09/12/2006 |
| 6815916 | Speed-control drive circuit for a D.C. brushless fan motor A speed-control drive circuit for a D.C. brushless fan motor includes a pulse width modulation input end for receiving an external pulse width modulation signal for controlling (and changing) the motor speed, and a motor winding drive circuit. The motor winding driv... | 11/09/2004 |
| 6809485 | Driving device for oscillatory actuator A driving device for an oscillatory actuator in which a FLL (Frequency Locked Loop) is employed for detecting an electromotive force generated in a driving coil resulting from mechanical oscillation during a period in which no driving current is supplied to the osci... | 10/26/2004 |
| 6763622 | Amplitude detection method and apparatus for high frequency impedance tracking sensorless algorithm A control system for an electric motor including an inverter for providing power to the electric motor, a controller for controlling the inverter, a first motor speed control block in the controller injecting a high frequency signal into the electric motor to determ... | 07/20/2004 |
| 6759819 | Rotation detection circuit of a dc brushless motor using a fixed bias voltage A rotation detection circuit of a dc brushless motor using a fixed bias voltage includes a transistor, and a signal adjuster. The signal adjuster is connected in series between the transistor and driver circuit of the dc brushless motor, for adjusting a signal outpu... | 07/06/2004 |
| 6731089 | Flexible and compact motor control module based on the can communication network The present invention relates to a flexible and compact motor control module based on the Controller Area Network (CAN) communication network. More specifically, the present invention relates to a motor control module which is based on the ISO11898 standard Controll... | 05/04/2004 |
| 6242884 | Dual stator winding induction machine drive A dual stator winding induction machine has two windings with input terminals which are supplied separately with drive power. The two stator windings have a different number of poles to essentially eliminate the magnetic coupling between the two windings ... | 06/05/2001 |
| 6161068 | Electric power steering control system An electric power steering control system reducing steering torque without making a driver feel uncomfortable torque oscillation, including a rotation speed observer for estimating the rotation speed of a motor based on the output of a torque sensor high ... | 12/12/2000 |
| 5786673 | Electric motor A fractional-power electric motor is provided to generate varying amounts of output torque supplied to a driven member over a wide range of RPM speeds so as to reduce power consumption on a battery-powered source. The electric motor includes a rotor and a... | 07/28/1998 |
| 5780984 | Apparatus and method for controlling rotation frequency of infinite variable-speed drive The invention provides an apparatus and a method for controlling the rotation frequency of an infinite variable-speed drive in which, when an error is caused in an output rotation frequency of the infinite variable-speed drive during a processing time per... | 07/14/1998 |
| 5661379 | Electric motor A fractional-power electric motor is provided to generate varying amounts of output torque supplied to a driven member over a wide range of RPM speeds so as to reduce power consumption on a battery-powered source. The electric motor includes a rotor and a... | 08/26/1997 |
| 5631528 | Elimination of motor negative voltages during motor brake A method for sensing motor commutation pulses during motor braking without creating negative voltages, which some junction isolated technologies substantially cannot tolerate. For instance, a commutation pulse sensing circuit containing junction isolated ... | 05/20/1997 |
| 5451856 | Device for the transmission of electrical power signals to a rotary assembly A device for the transmission of electrical power signals of variable frequencies and phases from a stationary assembly to a rotary assembly wherein the primary winding of a rotary transformer is supplied by an electrical power source of fixed frequency, ... | 09/19/1995 |
| 4236102 | Control system for spool drive of magnetic tape apparatus A control system for a magnetic tape apparatus having two spool carriers driven by D.C. drive motors to control the current in one of the motors in order to maintain a uniform tape transport speed comprises a pulse generator driven by the tape, a comparat... | 11/25/1980 |