Did You Know...
...Chester Carlson was a patent agent who tired of having to make multiple copies of patent applications using the only duplication method available at the time: carbon paper. In 1959 he came up with a new copying system and took it to IBM for evaluation. The "experts" at IBM determined potential sales to be only 5,000 units because people wouldn't want to use a bulky machine when they had carbon paper. Carlson's invention was the xerography process, the company founded on the system is Xerox.
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| Number | Title | Issue Date |
| 7358698 | Field-winding type of synchronous machine A field-winding type of synchronous machine comprises a stator with an armature winding wound phase by phase, a rotor having a rotor core with a field winding wound, and a circuit enabling an armature current to pass the armature winding, the armature current corres... | 04/15/2008 |
| 7350727 | Roller mill, particularly air-swept roller mill, and method for grinding materials with magnetizable, particularly iron-containing constituents, E. G. slag The invention relates to a roller mill, particularly an air-swept roller mill provided with a device for separating magnetizable constituents, particularly iron particles from the milling area. The invention also relates to a method for grinding materials with magne... | 04/01/2008 |
| 7339344 | Self tuning method and apparatus for permanent magnet sensorless control A plurality of parameters of a Permanent Magnet Synchronous Motor (PMSM) is determined by a motor controller for differentiating between a plurality of PMSMs. This is achieved by first applying regulated DC motor currents at a commanded fixed rotor angle and measuri... | 03/04/2008 |
| 7279865 | Method and apparatus for monitoring motor status using induced motor voltage A motor drive unit includes a controller, a voltage inverter, and a speed estimator. The controller is operable to generate at least one command signal for controlling a motor associated with the motor drive unit. The voltage inverter is operable to generate motor d... | 10/09/2007 |
| 7256563 | Method and device for the sensor reduced regulation of a permanent magnet excited synchronous machine A method and a device for providing field-oriented regulation of a synchronous machine excited by a permanent magnet, in which a direct-axis voltage component and a quadrature-axis voltage component of the control voltage for the synchronous machine are determined f... | 08/14/2007 |
| 7224138 | Method, system, and program product for feedback control of a target system utilizing imposition of a periodic modulating signal onto a command signal Feedback control of a target system is provided which utilizes the imposition of a periodic modulating signal onto a command signal of a controller. The command signal with the period modulating signal imposed thereon is input to the target system to be controlled. ... | 05/29/2007 |
| 7211984 | Start-up and restart of interior permanent magnet machines A method of starting a permanent magnet machine. A machine stator voltage in a stationary reference frame is sensed. An initial speed of a rotor of the machine is estimated based on the sensed voltage, and state variables of control algorithms are initialized based ... | 05/01/2007 |
| 7197390 | Electric vehicle with adaptive cruise control system A novel system for adaptively controlling an electric vehicle to maintain desired speed under variable driving conditions. The system includes a control circuit for producing a control signal to control an electric motor of the vehicle. The control signal is formed ... | 03/27/2007 |
| 7196491 | System and method for stall detection of a motor A motor starter system comprises solid state switches for connection between an AC line and motor terminals for controlling application of AC power to the motor. A voltage sensor senses AC line voltage and the motor terminal voltage. Current sensors sense motor curr... | 03/27/2007 |
| 7193387 | System and method for motor speed estimation using hybrid model reference adaptive system Motor drives, motor speed controllers, motor speed estimation systems, and methods are presented for controlling motor startup speed and for estimating motor speed during startup, in which a speed estimate controller provides a rotor speed estimate based on a first ... | 03/20/2007 |
| 7190145 | Method and apparatus for improving speed measurement quality in multi-pole machines A method and apparatus for improving speed measurement quality in systems having multi-pole machines is taught. The method compensates for pole misalignment by computing speed based upon moving average techniques. In one embodiment, a moving average speed averaged o... | 03/13/2007 |
| 7180263 | Synchronous motor control method and device Synchronous motor controlling apparatus and method controls power applied to minimize or eliminate speed variations of a synchronous motor due to variations in load imposed the motor. The rotational position of a rotor of the synchronous motor based on the input ter... | 02/20/2007 |
| 7109674 | Method and system for regulating the average electromagnetic torque of a rotating electrical machine, storage medium and data structure for carrying out the method A method is described for regulating the average electromagnetic torque of a polyphase rotating electrical machine, supplied with a polyphase voltage and a polyphase current that are generated by an inverter. The method comprises a step of controlling the machine, u... | 09/19/2006 |
| 7102313 | Apparatus and method for providing protection to electric traction motor of vehicle An apparatus provides protection to an electric traction motor of a vehicle. The vehicle has a first powertrain and a second powertrain. The first powertrain includes an engine and it is coupled with a first set of road wheels. The second powertrain includes the ele... | 09/05/2006 |
| 7095197 | Method and system for regulating instantaneous electromagnetic torque and storage medium for implementing the method A method is described of regulating the instantaneous electromagnetic torque of a polyphase rotating electrical machine equipped with stator and/or rotor windings supplied by a voltage and a current generated by an inverter formed of switches whose switching is cont... | 08/22/2006 |
| 7053587 | Apparatus for controlling three-phase AC motor on two-phase modulation technique An apparatus is provided to control a three-phase AC motor and comprises an inverter and a controller. The inverter powers the motor in response to a three-phase PWM command. The control circuit controls the inverter based on two modulation techniques selectively sw... | 05/30/2006 |
| 7026783 | Drive system A drive system includes a central power supply with a line-commutated converter and a DC/DC converter connected downstream of the line-commutated converter, and a plurality of inverters, each inverter having an output connected a load, for example a motor, and a DC ... | 04/11/2006 |
| 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 |
| 6984958 | Method for defining quadrature-axis magnetizing inductance of synchronous machine Method for defining quadrature-axis magnetizing inductance of a synchronous machine, the synchronous machine being supplied by an inverter. The method comprises steps, wherein the synchronous machine is started without load or with reduced load; the rotor current of... | 01/10/2006 |
| 6979967 | Efficiency optimization control for permanent magnet motor drive A method and system for modifying an estimated rotor angle for improved efficiency in a PMSM drive system. A module monitors a run command, a torque command, and an estimated speed; and in response thereto, generates an output correction angle for modifying the esti... | 12/27/2005 |
| 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 |
| 6940242 | Motor control system for dynamically changing motor energization current waveform profiles A control system is provided for a multiphase motor having a plurality of stator phase components, each stator phase component comprising a phase winding formed on a core element, and a rotor. A plurality of motor control schemes are stored in memory or calculated d... | 09/06/2005 |
| 6933704 | Slip-inducing rotation starting exciter for turbine generator A dynamoelectric machine combining the functions of an exciter, a turning motor, and a starting motor for a turbine. The machine operates in a first mode where the slip between a first stator winding and a first armature winding is positive and thus the magnetic fie... | 08/23/2005 |
| 6924617 | Position sensorless control algorithm for AC machine A control system for an electric motor having a stator and rotor including an inverter for providing power to the electric motor, a controller for controlling the inverter, a low speed control block to estimate the rotor angular position using stator current compone... | 08/02/2005 |
| 6919700 | Adaptive control of motor stator current waveform profiles Subject to user or system selection, one of the motor control schemes is accessed from the memory by a controller for implementation. The controller generates control signals that are applied to energization circuitry for supplying current to the phase windings with... | 07/19/2005 |
| 6646409 | Apparatus for controlling rotation speed of motor An apparatus for controlling the rotation speed of a motor, which is capable of controlling the rotation speed and the torque of the motor by detecting the input voltage and the input current of the motor without using a sensor for detecting the position ... | 11/11/2003 |
| 6310450 | Drive system of a brushless motor equipped with hall sensors self-discriminating the actual phasing of the installed sensors A method is for decoding three logic signals produced by three Hall effect sensors installed in an electronically-switched three-phase brushless motor according to a sequence of six driving phases to be switched synchronously with a rotor position. The me... | 10/30/2001 |
| 6150776 | Variable frequency motor starting system and method A variable frequency motor starting system has a variable frequency AC power supply for generating an AC power output signal applied to an AC motor. A controller is coupled to the variable frequency AC power supply for producing a control signal for adjus... | 11/21/2000 |
| 6114827 | Device for controlling a synchronous electric motor with a permanent magnet rotor A device for controlling a synchronous electric motor with a permanent magnet rotor. The device comprises a stator including a winding disposed around a stack of laminations and with which is associated a permanent magnet rotor. Controlled conductor devic... | 09/05/2000 |
| 6023137 | Use of traction inverter for supplying power for non-traction applications A method and apparatus for cranking of an internal combustion engine in an AC electric traction motor propelled vehicle using inverters normally coupled to supply power to each of a plurality of AC motors. The inverters have DC input terminals connected b... | 02/08/2000 |
| 5912543 | Circuit having a digital controller for operation of a synchronous T motor Electronic circuit having a digital controller operation of a synchronous motor. Precision motors for driving, for example, a video head drum in video recorders are normally designed as externally commutated synchronous motors. These motors are driven wit... | 06/15/1999 |
| 5852356 | DC/AC inverter for power supply to an electrical motor for the traction of a vehicle Disclosed is a dc/ac inverter for the supply of alternating current to the windings of a synchronous electrical motor, especially for the traction of an electrical vehicle. During each half-wave of the alternating current, the dc/ac inverter with solid-st... | 12/22/1998 |
| 5757161 | Apparatus and method for limiting the speed of an electric motor A motor control apparatus for detecting motor overspeed in an electric car to prevent destruction of the motor and assure the safety of the vehicle. Torque control is applied when the motor speed is less than a specified rotational velocity. When the moto... | 05/26/1998 |
| 5734135 | Procedure for starting an elevator In a system for starting elevator machinery driven by a synchronous motor, current is fed to the motor by a frequency converter and a traction sheave is connected to the motor to move the elevator car with hoisting ropes. The angle of the magnetic field o... | 03/31/1998 |
| 5731669 | Control apparatus for electric vehicle A control apparatus for an electric vehicle includes a device for detecting a degree of depression of an accelerator pedal in the electric vehicle, and for outputting an accelerator depression degree signal representing the detected degree of depression o... | 03/24/1998 |
| 5656911 | Circuit for driving permanent-magnet synchronous motor using proportional controller A driving device controls a permanent-magnet synchronous motor having a permanent magnet in its rotor using a voltage-type inverter supplying drive power for the synchronous motor, makes the torque of the synchronous motor and the d-axis current flowing i... | 08/12/1997 |
| 5635810 | Control system for a permanent magnet synchronous motor A control system for a permanent magnet synchronous motor includes a position estimator means having for cross correlating the back EMF of the unenergized winding with a reference waveform to determine the estimated position of the rotor for determining r... | 06/03/1997 |
| 5583411 | Synchronous motor control system for electric vehicle A synchronous motor control system controls a synchronous motor on an electric vehicle for propelling the electric vehicle in a propulsive mode or regenerating electric energy in a regenerative model. The synchronous motor control system has a rotational ... | 12/10/1996 |
| 5504404 | Method and apparatus for controlling motor In a method and an apparatus for controlling a motor, one type or a plurality of types of weakening current are previously set, a first torque command current determined from a speed deviation between a speed command to the motor and the present speed of ... | 04/02/1996 |
| 5436544 | Method of phase advancing compensation control for an AC synchronous motor An AC synchronous motor control method in which the optimum phase advancing control is executed not only in acceleration but also in deceleration of a motor. When a value P, which is obtained by multiplying a motor's revolutionary speed by a torque comman... | 07/25/1995 |
