Generator Field Circuit Control Patents (Class 318/158)
  • Patent number: 10247232
    Abstract: A rolling-element bearing cage or segment configured to guide at least one rolling element includes a first circumferential ring connected to a second circumferential ring by a plurality of axially extending bridges. A first one of the bridges includes a first axial portion that has a cross-section perpendicular to the axial direction and a cross sectional area and a peripheral length. The peripheral length of the cross section of the first axial portion is greater than a peripheral length of a smallest rectangle bounding the cross section.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: April 2, 2019
    Assignee: Aktiebolaget SKF
    Inventors: Volker Wendt, Padelis Katsaros
  • Patent number: 9746270
    Abstract: An unmanned turret having a turret ring gear and first and second electrical force-producing devices with the unmanned turret being rotatably mounted to a vehicle chassis, the turret drive mechanism including at least one ring gear independent of the turret ring gear, at least one manually-operable input component rotatably coupled to the at least one ring gear, the at least one input component accessible within the vehicle chassis, and at least one output component mechanically coupled to at least one of the first and second electrical force-producing devices of the unmanned turret to cause rotation of the at least one of the first and second electrical force-producing device. Another turret drive mechanism and an unmanned turret are also disclosed.
    Type: Grant
    Filed: June 4, 2014
    Date of Patent: August 29, 2017
    Assignee: LOCKHEED MARTIN CORPORATION
    Inventors: Craig Matthew Rose, Ronald Eugene Janka
  • Patent number: 9315105
    Abstract: A bidirectional charger subjects power supplied from an external power supply to voltage conversion and charges a main power storage device and an auxiliary power storage device. Furthermore, the bidirectional charger is configured to be able to convert power in a bidirectional manner so as to be able to subject power stored in the main power storage device or power stored in the auxiliary power storage device to voltage conversion and to output power to electrical outlet. The electrical outlet is configured to be able to output power to an electrical appliance including a home appliance. When a travel driving force increases during use of the electrical outlet, a PM-ECU controls the bidirectional charger in such a way that power stored in the auxiliary power storage device is subjected to voltage conversion and output power to the electrical outlet.
    Type: Grant
    Filed: March 7, 2012
    Date of Patent: April 19, 2016
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Yosei Sakamoto
  • Patent number: 8928260
    Abstract: A traction motor system calculates motor flux by generating a real time effective resistance of a resistance grid calculated from motor torque and measured voltage on a DC link. Calculating effective resistance avoids solely relying on DC link voltage, which can be influenced by conditions such as wheel slip and drop out of one or more resistance grids. The effective resistance calculation is based on nominal motor values using known power levels and conditions. From these nominal values and the effective resistance, various scaling factors based on actual motor power can be generated and used to adjust a nominal flux reference to more accurately reflect actual motor flux. The scaling factors include power and torque scaling factors and a resistance scaling factor that is active during conditions such as wheel slip.
    Type: Grant
    Filed: October 18, 2012
    Date of Patent: January 6, 2015
    Assignee: Caterpillar Inc.
    Inventors: Alexander Cameron Crosman, III, Joshua M. Williams
  • Patent number: 8680796
    Abstract: To provide an upper limit of a generated voltage or generated torque, to thereby prevent the occurrence of an overvoltage or excessive torque during power generation, a control selection section (308) chooses and outputs a minimum value between a control output of a generated voltage control section (306) for controlling a field current so that a B-terminal voltage of a polyphase AC generator-motor coincides with a generated voltage command and a control output of a generated torque control section (307) for controlling, based on the B-terminal voltage and a rotation speed, the field current so that generated torque of the polyphase AC generator-motor coincides with a generated torque command.
    Type: Grant
    Filed: April 10, 2012
    Date of Patent: March 25, 2014
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenji Nakajima, Masato Mori, Kenichi Akita, Mitsunori Tabata
  • Patent number: 8253357
    Abstract: An electric drive system includes a prime mover connected to a generator, which is controlled in part by an excitation current. The generator makes electrical power available on a dc link. A method of load demand and power generation balancing within the electric drive system includes determining a voltage of the dc link and determining a torque command by an operator of the system. A speed for each of one or more drive motors receiving power from the dc link is determined and normalized to derive an average motor speed. A mechanical power being commanded is derived based on the average motor speed and the torque command. A predicted excitation current that is required to achieve the derived mechanical power is determined and an actual excitation current is determined based on the predicted excitation current. The actual excitation current is then applied to the generator.
    Type: Grant
    Filed: September 15, 2008
    Date of Patent: August 28, 2012
    Assignee: Caterpillar Inc.
    Inventor: Bradley Bailey
  • Patent number: 8164296
    Abstract: A method and an apparatus are described for determining a field current through a field winding in an electrical machine with a stator and a rotor. The electrical machine includes a field-circuit transformer to produce, by induction of an electrical current on the rotor side, field current with which a field winding is energized in order to generate an excitation magnetic field. The method includes driving the primary side of the field-circuit transformer to produce a field current in the rotor, which is derived from the current induced on the secondary side in the field-circuit transformer; measuring one or more phase currents in one or more primary-side phases of the field-circuit transformer; determining a maximum value depending on the one or more measured phase currents; determining the field current through the field winding depending on the determined maximum value.
    Type: Grant
    Filed: March 10, 2010
    Date of Patent: April 24, 2012
    Assignee: ABB Schweiz AG
    Inventor: John Eckerle
  • Patent number: 8080950
    Abstract: A system and method are provided for controlling the speed of a motor driving a load that is electrically connected to a generator driven by an engine, through use of a first control feedback loop configured to control the rotor flux of the motor by controlling the field excitation of the generator, and a second control feedback loop configured to control the speed of the motor by controlling the throttle position of the engine.
    Type: Grant
    Filed: March 15, 2010
    Date of Patent: December 20, 2011
    Assignee: Unico, Inc.
    Inventors: Thomas L. Beck, Michael D. Dry, Mark E. Garlow, Michael O. Lucas, Michael A. MacDonald, Ronald G. Peterson
  • Publication number: 20100066277
    Abstract: An electric drive system includes a prime mover connected to a generator (204), which is controlled in part by an excitation current. The generator (204) makes electrical power available on a dc link (312). A method of load demand and power generation balancing within the electric drive system includes determining a voltage of the dc link (312) and determining a torque command by an operator of the system. A speed for each of one or more drive motors (210) receiving power from the dc link (312) is determined and normalized to derive an average motor speed (712). A mechanical power (718) being commanded is derived based on the average motor speed (712) and the torque command. A predicted excitation current (730) that is required to achieve the derived mechanical power (718) is determined and an actual excitation current (734) is determined based on the predicted excitation current (730). The actual excitation current (734) is then applied to the generator (204).
    Type: Application
    Filed: September 15, 2008
    Publication date: March 18, 2010
    Applicant: CATERPILLAR INC.
    Inventor: Bradley Bailey
  • Patent number: 7531974
    Abstract: A motor control device is disclosed that reduces the shock caused by torque increase during switching output of a motor's power generator from PWM wave voltage driving to square-wave voltage driving. Switching of PWM wave voltage driving and square-wave voltage driving is determined based on rotation speed of the motor and a torque instruction value. When switching from PWM wave voltage driving to square-wave voltage driving occurs, the voltage output of the power generator is reduced. When generated voltage V drops below a specified threshold voltage, PWM wave voltage driving is switched to square-wave driving.
    Type: Grant
    Filed: December 14, 2005
    Date of Patent: May 12, 2009
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Hideaki Ohtsuka, Hidehiko Sugita
  • Patent number: 7081725
    Abstract: The present invention includes a power drive electronics apparatus connected between a frequency variable generator and an electric motor. The power drive electronics apparatus includes a three-phase diode rectifier having a three-phase AC input, a positive DC output terminal and a negative DC output terminal. A capacitor is connected between the positive DC output terminal and said negative DC output terminal. The three-phase AC input is operably connected to the electric motor and the positive DC output terminal is operably connected to the frequency variable generator's rotor winding. The power drive apparatus also includes a diode having an anode and a cathode, wherein the cathode is connected to the positive DC output terminal of the three-phase diode rectifier, and the anode is connected to a battery.
    Type: Grant
    Filed: February 6, 2004
    Date of Patent: July 25, 2006
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Stanley S. Seely, Zilai Zhao, Carl David Klaes, Melody Abesamis
  • Patent number: 6977475
    Abstract: Each of the phases of coil in an armature winding of a dynamoelectric machine is constructed so as to have six turns, an inverter has a plurality of element-diode sets, each element-diode set including a pair of switching elements connected in series and diodes connected in parallel to the switching elements, connection points of the switching elements connected in series are connected to the dynamoelectric machine, a control apparatus controls the inverter such that the dynamoelectric machine is driven by supplying electric power from a first battery to the dynamoelectric machine during starting of an engine, and alternator mode electric power generation is performed by the dynamoelectric machine at least in a normal rotational speed region of the engine.
    Type: Grant
    Filed: January 29, 2003
    Date of Patent: December 20, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masaru Kuribayashi, Yoshihito Asao
  • Patent number: 6888329
    Abstract: A method of controlling an electric rotating machine for a vehicle includes an electric rotating machine (1) including a rotator having a field winding (5) and a stator having an armature winding (3), a field current controller (9) for controlling a field current supplied from a direct-current power supply to the field winding (5), and a power converter (6) for converting a direct-current power into an alternating-current power and applying the power to the armature winding (3). When the field current controller (9) starts to supply a current to the field winding (5) for starting an internal combustion engine, the power converter (6) supplies a power to the armature winding (3) so that magnetic flux in a direction opposite to that generated by the field winding (5) is generated simultaneously with or immediately before starting the power supply.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: May 3, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masaya Inoue, Haruyuki Kometani, Toshiyuki Yoshizawa, Masahiko Fujita, Tsunenobu Yamamoto, Yoshihito Asao, Shinji Nishimura
  • Patent number: 6731081
    Abstract: A vehicle alternator includes a permanent magnet rotor, a stator having armature coils, and a rectifier circuit. In the rectifier circuit, schottky barrier diodes and FETs are connected in series so that the forward directions of the schottky barrier diodes and parasitic diodes of the MOSFETs are opposite. The schottky barrier diodes are connected between the MOSFETs and the armature coils.
    Type: Grant
    Filed: March 21, 2002
    Date of Patent: May 4, 2004
    Assignee: Denso Corporation
    Inventors: Shin Kusase, Tsutomu Shiga
  • Patent number: 6392371
    Abstract: A power generator in which the rotor's mechanical rotation speed and the output frequency can be varied substantially independently of each other through electronic controls, to achieve results such as better match between speed and load regime of the primary mover and the generator's output.
    Type: Grant
    Filed: April 3, 2000
    Date of Patent: May 21, 2002
    Assignee: Cheng Power Systems, Inc.
    Inventors: Dah Yu Cheng, Alan L. Helgesson
  • Patent number: 6133702
    Abstract: A multi-function apparatus and a method for performing the functions of a starter, alternator and engine stabilization system for an engine of a motor vehicle. The apparatus comprises a rotor, a stator and a switching/detection system associated with the stator. The stator comprises three independent stator sectors which each comprise a plurality of independent stator coils. The rotor comprises a plurality of rotor poles about its periphery. The rotor is secured to the flex plate of the engine and the stator sectors are secured to the bell housing of the vehicle's power train. The stator coils each protrude through opening formed in the bell housing such that the rotor poles are closely adjacent the stator coils without contacting the stator coils as the rotor rotates.
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: October 17, 2000
    Assignee: Chrysler Corporation
    Inventors: Gardiner A. Noble, Mark Ciuffetelli, Jean P. Mallebay-Vacqueur, Christopher P. Thomas
  • Patent number: 5998944
    Abstract: An apparatus and method for controlling a lifting magnet (12) of a materials handling machine (10) to eliminate arcing between contacts (70-80) within the magnet controller (26) as is well as is large voltage spikes. The controller (26) selectively excites the shunt field windings (66,68) of a direct current generator (22). The magnitude and direction of the current passing through the shunt field windings (66,68) is varied by the magnet controller (26) to control the magnitude and polarity of the voltage at the generator output (23). The armature (60) of the generator (22) is rotatably driven by a hydraulic motor at an essentially constant speed to minimize voltage variations at the output (23) of the generator (22). At least the drop cycle is controlled through use of a current transducer (200) that senses current flowing to the lifting magnet so that the electronic controller is able to control the flow of current to the lifting magnet based upon the sensed current in the magnet circuit.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: December 7, 1999
    Assignee: Caterpillar Inc.
    Inventors: Ronald W. Clutter, Kenneth J. Chlad, Timothy L. Cooper, Charles A. Robinson
  • Patent number: 5977730
    Abstract: A hydraulic circuit (124) is defined in a manifold (130) which may be aluminum, steel, or any other suitable material. The circuit (124) regulates the flow of hydraulic fluid to the hydraulic motor (120) and thus ensures that the motor rotates at an essentially constant speed, independent of the speed of the hydraulic pump (122) supplying the circuit. The circuit includes a pressure compensated flow control valve assembly (140) with an adjustable flow control valve (142) that regulates the flow of hydraulic fluid to the motor (120). The assembly (140) also includes a balanced piston-type pressure compensator (144) that ensures a select pressure differential across the flow control valve (142) such that the flow through the valve (142) remains at least essentially constant. This constant flow through the pressure compensated flow control valve assembly (140) ensures an essentially constant rotational speed of the motor (120).
    Type: Grant
    Filed: August 3, 1998
    Date of Patent: November 2, 1999
    Assignee: Caterpillar Inc.
    Inventors: Ronald W. Clutter, Kenneth J. Chlad, Timothy L. Cooper, Charles A. Robinson
  • Patent number: 5959416
    Abstract: An apparatus and method for controlling a lifting magnet (12) of a materials handling machine (10) to eliminate arcing between contacts (70-80) within the magnet controller (26) as well as large voltage spikes. The controller (26) selectively excites the shunt field windings (66,68) of a direct current generator (22). The magnitude and direction of the current passing through the shunt field windings (66,68) is varied by the magnet controller (26) to control the magnitude and polarity of the voltage at the generator output (23). The armature (60) of the generator (22) is rotatably driven by a hydraulic motor at an essentially constant speed to minimize voltage variations at the output (23) of the generator (22). The magnet controller (26) includes a programmable logic controller (40) which selectively opens and closes the contactors (70-80) within the controller (26).
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: September 28, 1999
    Assignee: Caterpillar Inc.
    Inventors: Ronald W. Clutter, Kenneth J. Chlad, Timothy L. Cooper, Charles A. Robinson
  • Patent number: 5767636
    Abstract: To provide a vehicle power generating apparatus capable of transmitting plural kinds of control signals from an external control device to a generated voltage control unit provided in a generator for power generation control while curbing increases in the size of apparatus or wiring required and without degrading the noise reduction characteristics, a generated voltage control device is normally disposed integrally with a generator for maintaining the generated voltage at a predetermined target level. For transmission of a vehicle condition signal from an external control device to the generated voltage control device, the vehicle condition signal is converted into a binary pulse train signal before being transmitted. The generated voltage control device holds the binary pulse train signal received or a vehicle condition signal decoded from the binary pulse signal until the next reception. Thereby, complicated power generation control can be achieved with a small amount of communications.
    Type: Grant
    Filed: January 30, 1996
    Date of Patent: June 16, 1998
    Assignee: Nippondenso Co., Ltd.
    Inventors: Wakako Kanazawa, Fuyuki Maehara, Yasuhiro Takase
  • Patent number: 5473228
    Abstract: A control method for an electrical appliance in a hybrid vehicle. When the electric appliance is connected, the output of the engine is maintained by reducing the output of the generator by the equivalent of the power consumed by the electric appliance while maintaining the revolution speed of the engine. The revolution speed of the engine is then gradually increased by adjusting the field current of the generator while monitoring the output of the generator. When the output of the engine is increased by the power consumed by the electric appliance, the engine is operated at a constant revolution speed and a constant output at the operation point on the output line of the engine with WOT. Thus, the engine is prevented from stopping due to a rapid increase in the load. Owing to a gentle change in the output, the emission is favorable. Since the output of the engine does not deviate from the output line of the engine with WOT (wide open throttle), the fuel consumption is also good.
    Type: Grant
    Filed: September 28, 1994
    Date of Patent: December 5, 1995
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Yoshihide Nii
  • Patent number: 5137119
    Abstract: A current regulator phase controls a power signal to control silicon controlled rectifiers arranged in a bridge. The silicon controlled rectifiers excite a generator field of an elevator drive. Discontinuity in the generator field current, caused by the inductive load and latching and holding currents in the silicon controlled rectifiers, is detected to provide an analog discontinuity signal. The analog discontinuity signal is converted to digital form and used to dynamically alter the gain and response of the regulator.
    Type: Grant
    Filed: September 28, 1990
    Date of Patent: August 11, 1992
    Assignee: Otis Elevator Company
    Inventors: Herbert K. Horbruegger, Mustapha Toutaoui
  • Patent number: 4982123
    Abstract: The problem of providing field power to a stationary main generator rotor is addressed such that it can be used as a synchronous or brushless dc motor. To that end, a dynamoelectric machine performs the dual-functions of an exciter generator and a rotating transformer integrated into a single unit (14). The heads (64) of the stator salient poles (60) include pole slots (68) for a primary transformer winding (34) for the rotating transformer, while the rotating armature winding (36) serves as the transformer secondary. To assist in starting the engine (10), external ac power (42) is applied to the primary transformer windings (34), coupled to armature windings (36), and rectified (44) to develop dc field power for the main generator (12).
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: January 1, 1991
    Assignee: Sunstrand Corporation
    Inventor: Bernard A. Raad
  • Patent number: 4939441
    Abstract: An excitation system for a brushless generator includes an exciter portion having a set of polyphase exciter field windings and an additional exciter field winding disposed in a stator of the generator, a source of polyphase, constant-frequency AC power and circuitry coupled to the set of polyphase field winding for connecting the source of polyphase, constant-frequency AC power thereto at a beginning of operation in a starting mode whereby AC power is induced in an exciter portion armature winding by transformer action. AC power is further provided to armature windings of a main generator portion to thereby cause a rotor of the generator to accelerate. An autotransformer is provided to reduce the voltage provided by the source of polyphase AC power prior to application of such power to the polyphase field windings so that the need for an auxiliary inverter is obviated.
    Type: Grant
    Filed: October 27, 1989
    Date of Patent: July 3, 1990
    Assignee: Sundstrand Corporation
    Inventor: P. John Dhyanchand
  • Patent number: 4751978
    Abstract: A power assist steering system in which electrical power to drive the electric assist motor is selectively provided from either the alternator or the battery depending upon the vehicle speed and applied steering torque. An electronic control unit controls the output voltage from the alternator by controlling current through the alternator field coil.
    Type: Grant
    Filed: March 16, 1987
    Date of Patent: June 21, 1988
    Assignee: TRW Inc.
    Inventors: Gilbert H. Drutchas, deceased, John S. Borza
  • Patent number: 4709203
    Abstract: The invention relates to an on board power supply, particularily for a ship propelled by a variable speed diesel engine (1), comprising a first alternator (2) coupled to a diesel engine, an electronic regulator (4) for the first alternator, a rectifier (5) for rectifying the output current of the first alternator, a direct current motor (6) powered from the output of the rectifier, and a second alternator (8) coupled to the direct current motor.It also comprises means (13) for selectively feeding the regulator of the first alternator from the output (12) of the first alternator or from the output (11) of the second alternator.
    Type: Grant
    Filed: October 3, 1985
    Date of Patent: November 24, 1987
    Assignee: Moteurs Leroy-Somer
    Inventors: Yves M. J. P. Roux, Patrice G. L. Pitaud
  • Patent number: 4543513
    Abstract: The control of a quantity (voltage, phase) relating to a generator-motor pair in an electric power station is accomplished by generating a pulse sequence associated with the quantity to be controlled, generating a predetermined reference pulse sequence and detecting the relative phase shift between the two pulse sequences. This phase shift, or an integrated value of a number of successive phase shifts, controls a double ramp generator, the sign and slope of which are proportional to the detected phase shift. The integrated signal is employed to vary the magnetic induction of the rotor, i.e., field excitation of the generator, to balance the system.
    Type: Grant
    Filed: July 27, 1983
    Date of Patent: September 24, 1985
    Inventor: Maurizio Checchetti
  • Patent number: 4494050
    Abstract: A method and apparatus for reducing oscillations in input electrical power to a Ward-Leonard drive system which is subject to variations in mechanical loading, the technique utilizing a notch filter in the feedback path to the dc generator, the notch filter being turned to match the resonant frequency of the synchronous motor.
    Type: Grant
    Filed: October 11, 1983
    Date of Patent: January 15, 1985
    Assignee: The Broken Hill Proprietary Company Limited
    Inventors: Noel R. Godfrey, Larry S. Parkes, Richard H. Treacy
  • Patent number: 4383213
    Abstract: A dynamoelectric machine having a multiple of three poles and a corresponding multiple of three brushes is disclosed. Each of the poles are wound poles, two of each group of three poles being excited with a constant excitation during normal operation, the third of each group of poles being a control pole, excited so as to produce a flux that both varies in magnitude and reverses in polarity. With an input voltage connected to first and second brushes of each group of three, an output voltage may be derived from first and third brushes in a magnitude determined by the polarity and intensity of the field of the control pole. The machine is also adapted to provide mechanical output power from its rotating shaft, and also to accept input power from its rotating shaft. The output voltage obtainable may be varied between zero and the value of the input voltage, and also increased above the input voltage, and decreased below zero, reversing polarity.
    Type: Grant
    Filed: July 27, 1981
    Date of Patent: May 10, 1983
    Inventor: Joseph M. Tyrner
  • Patent number: 4323830
    Abstract: A d.c. generator is connected in series opposed to the polarity of a d.c. power source supplying a d.c. drive motor. The generator is part of a motor-generator set, the motor of which is supplied from the power source connected to the motor. A generator field control means varies the field produced by at least one of the generator windings in order to change the effective voltage output. When the generator voltage is exactly equal to the d.c. voltage supply, no voltage is applied across the drive motor. As the field of the generator is reduced, the drive motor is supplied greater voltage until the full voltage of the d.c. power source is supplied when the generator has zero field applied. Additional voltage may be applied across the drive motor by reversing and increasing the reversed field on the generator. The drive motor may be reversed in direction from standstill by increasing the generator field so that a reverse voltage is applied across the d.c. motor.
    Type: Grant
    Filed: May 21, 1980
    Date of Patent: April 6, 1982
    Assignee: The Franklin Institute
    Inventors: Charles A. Belsterling, John Stone
  • Patent number: 4292531
    Abstract: A self-propelled traction vehicle equipped with an a-c traction motor energized by the a-c output of a controlled current inverter is propelled by a process comprising the steps of providing a traction alternator on-board the vehicle, rotating the rotor of the alternator, exciting the field winding of the alternator, converting the output current of the armature windings of the alternator to a unidirectional current, and feeding the unidirectional current to d-c terminals of the controlled current inverter without appreciably smoothing the unidirectional current. A system for carrying out this process is also disclosed.
    Type: Grant
    Filed: March 2, 1979
    Date of Patent: September 29, 1981
    Assignee: General Electric Company
    Inventor: Dennis F. Williamson
  • Patent number: 4232255
    Abstract: A control system for regulating the speed of a truck-mounted material conveyor includes a direct current drive motor and a truck-driven shunt generator for providing power to the motor. A control circuit has a reference input representing desired delivery rates in material weight per unit of distance and a truck speed input. A multiplier circuit converts the inputs to a delivery rate in terms of material weight per unit of time at the current truck road speed. Generator and conveyor speed feedback loops are provided to maintain a desired conveyor speed despite variations in truck engine speed or slippage at the conveyor.
    Type: Grant
    Filed: November 6, 1978
    Date of Patent: November 4, 1980
    Inventor: Eric T. Carlen
  • Patent number: 4179729
    Abstract: A power conversion system for converting between electrical power at different frequencies, including a rotary electrical machine including a rotor, a stator, first and second independently controllable field windings, and at least one armature winding for each phase; a switching circuit including a plurality of switching devices and having first terminal means interconnected with the armature winding which carries a high frequency signal established by the machine, and a second terminal for interconnection with an impedance establishing a lower frequency signal; the first field control circuit for monitoring the machine to sense phase difference between the optimum zero crossings and actual zero crossings of the higher frequency signal for driving the first field winding to adjust the phase of the higher frequency signal to minimize the phase difference; a second field control circuit for modulating the higher frequency signal carried by the armature winding with the lower frequency signal and for monitoring
    Type: Grant
    Filed: April 15, 1977
    Date of Patent: December 18, 1979
    Assignee: The Charles Stark Draper Laboratory, Inc.
    Inventors: William E. Stanton, David B. Eisenhaure, George A. Oberbeck, Kenneth Fertig
  • Patent number: 4164785
    Abstract: A multiphase to single phase electrical energy converter wherein the frequency is converted from a relatively high frequency, in order of 1,000 hertz, to a relatively low frequency, as for example, normal household frequency of 60 hertz. A three-phase alternator is driven by an internal combustion engine, the output of the alternator being fed to a full-wave bridge circuit and finally to an inverter. The output of the bridge circuit is acted on by a resolver. The resolver is utilized to control the delivery of energy from the alternator to the inverter to provide an average current or power to the inverter which increases and decreases in a unipolar sinusoidal form at a frequency which is twice the desired output frequency. The inverter is utilized to invert every other cycle of the output from the resolver. Thus, the power from the inverter will take the form of an alternating sinusoidal waveform at 60 hertz.
    Type: Grant
    Filed: December 8, 1977
    Date of Patent: August 14, 1979
    Assignee: Tenna Power Corporation
    Inventors: Thomas A. Young, Jay W. Gustin
  • Patent number: 3967171
    Abstract: Propulsion control system for electrically powered vehicles, typically heavy duty off-road type work vehicles having electric motor driven wheels. In embodiment shown, power is supplied from direct current generator driven by internal combustion engine. Motor and generator field excitation is automatically varied responsive to selected machine operating conditions and improved means are provided to accomplish such variation. The provision and application of certain propulsion system parameters effects improved machine performance with minimum demand for operator skill and attention.
    Type: Grant
    Filed: May 1, 1974
    Date of Patent: June 29, 1976
    Assignee: R. G. LeTourneau, Inc.
    Inventors: Aaron D. Friend, Hilmer C. Lindahl
  • Patent number: 3953775
    Abstract: Propulsion control system for electrically powered vehicles, typically heavy duty off-road type work vehicles having electric motor driven wheels. In embodiment shown, power is supplied from direct current generator driven by internal combustion engine. Motor and generator field excitation is automatically varied responsive to selected machine operating conditions and improved means are provided to accomplish such variation. The provision and application of certain propulsion system parameters effects improved machine performance with minimum demand for operator skill and attention.
    Type: Grant
    Filed: March 23, 1973
    Date of Patent: April 27, 1976
    Assignee: R. G. LeTourneau, Inc.
    Inventors: Aaron D. Friend, Hilmer C. Lindahl