Plural Excitation Windings Patents (Class 322/63)
  • Patent number: 11211836
    Abstract: A permanent magnet generator, includes a cylindrical rotor assembly having a set of circumferentially-spaced permanent magnets arranged at an outer radius of the rotor assembly, and spaced from one another by non-magnetic spacing element, and a stator assembly configured to coaxially receive the rotor assembly. The stator assembly includes a cylindrical stator core, a circumferentially spaced set of posts extending from the stator core and defining a set of stator slots between adjacent posts, and a set of conductive windings wound about the stator slots.
    Type: Grant
    Filed: May 3, 2019
    Date of Patent: December 28, 2021
    Assignee: GE Aviation Systems LLC
    Inventors: Hao Huang, Xiaochuan Jia
  • Patent number: 10651711
    Abstract: The magnetless rotary electric machine includes an annular rotor, an outer stator and an inner stator. The annular rotor includes an annular rotor yoke portion, outer salient poles, outer rotor coils, inner salient poles, inner rotor coils, first rectifying devices and second rectifying devices. The first salient pole is configured to be magnetized by an induction current induced by the first coil. Each of the first rectifying devices is configured to rectify current such that a direction of a magnetic pole of the first salient pole is a first direction. The second salient pole is configured to be magnetized by an induction current induced by the second coil. Each of the second rectifying devices is configured to rectify current such that an direction of a magnetic pole of the second salient pole is a second direction. The second direction is a reverse direction to the first direction.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: May 12, 2020
    Inventors: Hidekazu Igarashi, Eiji Yamada
  • Publication number: 20130033238
    Abstract: In an excitation device for stators of generators for high-induction measurement, the greatest possible compensation of the reactive power requirement is achieved. Depending on the size and energy requirement of the generator, a number of individual excitation modules with a corresponding number of individual excitation windings are provided, wherein a minimum necessary total excitation current can be supplied by superimposing the individual currents of the excitation windings.
    Type: Application
    Filed: June 28, 2012
    Publication date: February 7, 2013
    Applicant: ALSTOM Technology Ltd
    Inventor: Max Hobelsberger
  • Patent number: 7746038
    Abstract: A controller employed in conjunction with a synchronous generator monitors the output voltage of the generator. The controller employs the monitored output voltage as feedback that is used to control the excitation provided to an exciter field winding. In addition, the controller applies a control loop to the monitored output voltage that detects and modifies voltage ripple signals within the monitored output voltage to generate a compensated signal that is used to control the excitation to the exciter field winding. In particular, by detecting and modifying voltage ripple signals within the monitored output voltage, the controller is able to counteract armature reaction voltage ripples caused by unbalanced short-circuit faults, thereby preventing the build-up of voltage on the DC link.
    Type: Grant
    Filed: January 2, 2008
    Date of Patent: June 29, 2010
    Assignee: Hamilton Sundstrand Corporation
    Inventors: Vijay K. Maddali, John F. Defenbaugh
  • Patent number: 7638985
    Abstract: A self-excited, switched reluctance generator obtains excitation energy from a capacitor bank via an excitation bus during normal operation. During a short-circuit or load fault, one or more phases of the generator provide power to the excitation bus while the remaining phases send current to a faulted positive bus. The system does not require an external battery or power source for excitation energy. The system is capable of resuming normal operation after the load bus fault.
    Type: Grant
    Filed: August 17, 2006
    Date of Patent: December 29, 2009
    Assignee: Hamilton Sundstrand Corporation
    Inventor: Piyush Tandon
  • Patent number: 7545125
    Abstract: The present invention relates to a six-phase generator for a motor vehicle having two three-phase systems displaced with respect to one another by 30°, the phase windings of one of the three-phase systems being positioned in a wye connection and the phase windings of the other three-phase system being positioned in a delta connection.
    Type: Grant
    Filed: June 17, 2004
    Date of Patent: June 9, 2009
    Assignee: Robert Bosch GmbH
    Inventors: Gert Wolf, Klaus Rechberger
  • Patent number: 7375499
    Abstract: A fault-tolerant synchronisation source for excitation control of a three-phase generator system that combines point of regulation (POR) signals representing parameters comprising voltage and current for each phase at the POR to generate a fault-tolerant synchronisation signal.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: May 20, 2008
    Assignee: Hamilton Sundstrand Corporation
    Inventors: Vijay K. Maddali, Michael J. Hanson
  • Patent number: 6933704
    Abstract: 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 fields interact and operate as a motor to turn the turbine. In a second mode the slip is negative as the turbine turns the shaft and the first stator winding and the first armature operate as an exciter for supplying excitation to the rotating field winding of a main generator.
    Type: Grant
    Filed: October 11, 2002
    Date of Patent: August 23, 2005
    Assignee: Siemens Westinghouse Power Corporation
    Inventors: Robert J. Nelson, Dennis Perttula, Stephen Cates, Aaron Staley
  • Patent number: 6864667
    Abstract: An electrical generator having a stator, a rotor, two windings, and a rectifying circuit. The stator has a first winding arranged in a wye configuration and a second winding arranged in a delta configuration. The wye winding is wound in a full pitch pattern around three stator teeth while the delta winding is wound in a short pitch pattern around two stator teeth, or vice versa. The wye and delta windings are connected to a single bridge rectifying circuit.
    Type: Grant
    Filed: January 18, 2001
    Date of Patent: March 8, 2005
    Assignee: Delphi Technologies, Inc.
    Inventors: Duane Joseph Buening, Ronald John Krefta
  • Patent number: 6750636
    Abstract: An electric power generating system comprising: a generator including an alternator and regulator, the regulator including a normal field control and a redundant field control with a default field command and a selector for selecting between the normal field control and the redundant field control. Further disclosed, is a method of providing excitation to an alternator, comprising: receiving a field default signal indicative of an inoperative normal field control and a normal field command responsive to the normal field control, indicative of a desired duty cycle command to a field coil of an alternator. The method further includes determining if a supply voltage is greater than a selected value and formulating a default field command; transmitting a field drive responsive to the default field command to a field coil of the alternator if the field default signal is asserted.
    Type: Grant
    Filed: April 24, 2002
    Date of Patent: June 15, 2004
    Assignee: Delphi Technologies, Inc.
    Inventors: Lary Robert Hocken, Stephen Wayne Anderson
  • Patent number: 6531685
    Abstract: A method and apparatus for providing power from an engine includes a one or more output windings in of slots on a generator. A plurality of exciter windings are in magnetic communication with the one or more output windings. The exciter windings are also placed in slots in the generator. The location of slots for the various windings is chosen to produce a desired output. A power supply is in electrical communication with the one or more output windings. Preferably, there are as many or more exciter windings as there are output windings.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: March 11, 2003
    Assignee: Illinois Tool Works Inc.
    Inventor: Alan F. Smith
  • Patent number: 6522106
    Abstract: An automatic voltage-regulating system for an engine generator includes an output voltage detecting device for extracting a single-phase AC output voltage from an output winding wound around a stator to output a detection voltage, and a switching device for regularizing the output voltage to be substantially at a constant level by selectively conducting and cutting off of a field current supplied from an exciting winding wound around the stator to a field winding wound around a rotor. Depending upon whether the detection voltage is higher or lower than a predetermined value, the charged voltage of a condenser for smoothing a rectified output from the field winding is divided by a pair of voltage dividing resistors. A switch device is forcibly turned on by a detection voltage in response to the voltage at a connection point between the pair of resistors exceeding a predetermined voltage value, to thereby cause the smoothing condenser to be discharged.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: February 18, 2003
    Assignees: Sawafuji Electric Co., Ltd., Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Takehiro Matsumoto, Takao Tamechika
  • Patent number: 6486640
    Abstract: Disclosed is a control system for a variable frequency generator including a main stator winding for providing a generator output, excited by a main rotor winding, and a main exciter rotor winding for energizing the main rotor winding, excited by a main exciter field winding. The control system includes: a plurality of inputs adapted to receive respective signals corresponding to respective generator operating parameters; an output adapted to drive the main exciter field winding; and a plurality of negative feedback loops between the output and the inputs. Each loop includes a respective stability compensation network operable to process a feedback signal corresponding to one of the generator operating parameters.
    Type: Grant
    Filed: February 21, 2001
    Date of Patent: November 26, 2002
    Assignee: Lucas Industries Limited
    Inventor: Christopher John Adams
  • Patent number: 6188204
    Abstract: An AC generator whose field winding (4) on the rotor is excited by AC so that the resultant speed of the rotating field is the algebraic sum of the rotor speed and the speed of the field relative to the rotor itself. This makes it possible to generate AC at a frequency different from that of conventional DC excited generators by the appropriate choice of the frequency of the AC input to the rotor field circuit. It enables the stabilization of the output frequency of the alternator when speed changes occur, by the adjustment of the AC frequency of the rotor input. The AC fed to the rotor is from an auxiliary winding (3) which may be housed on the rotor itself, thereby eliminating the need for any brushes or slip rings. The AC is induced in the auxiliary rotor winding by having an auxiliary winding on the stator (2), distinct from the main stator winding (1). The input to the stator auxiliary winding may be from an inverter (5) whose frequency may be adjustable.
    Type: Grant
    Filed: August 5, 1999
    Date of Patent: February 13, 2001
    Inventors: Joseph Vithayathil, John J. Vithayathil
  • Patent number: 6160384
    Abstract: A power device including a magneto and a rectification circuit for rectifying an output of the magneto is provided which is capable of adjusting an output of the magneto without any specific control circuit. A field adjusting excitation coil is arranged on a side of a stator of the magneto so as to generate a field adjusting magnetic flux when it is excited, resulting in a magnet field of the magneto being varied by means of the magnetic flux. The field adjusting excitation coil is connected to an intermediate portion of a current flow circuit for a load current, to thereby be excited by the load current, so that a magnet field of a rotor of the magneto is varied depending on the load current, leading to adjustment of an output of the magneto.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: December 12, 2000
    Assignee: Kokusan Denki Co., Ltd.
    Inventors: Yutaka Inaba, Tetsuya Kondo
  • Patent number: 5764036
    Abstract: A multiple output synchronous generator in accordance with the instant invention comprises a stator having a first stator winding having a number of poles p and a second stator winding having a number of poles 2*p*n where p and n are any whole numbers, the first and second stator windings being wound utilizing a phase belt winding configuration such that the first stator winding is magnetically decoupled from the second stator winding preventing interaction therebetween. The generator additionally comprises a rotor rotatably disposed within the stator defining an airgap therebetween. The rotor has a first field winding of a first polarity and a second field winding having a second number of windings wound thereon for generating a flux across the airgap such that the flux induces a voltage in the first and second stator windings.
    Type: Grant
    Filed: March 8, 1995
    Date of Patent: June 9, 1998
    Assignee: Sundstrand Corporation
    Inventors: Jayant G. Vaidya, Madan L. Bansal, Hassan Mansir
  • Patent number: 5714821
    Abstract: A three phase four pole alternating current generator includes an AC exciter including a series winding for each phase of the main generator windings and a shunt winding for each of the main phase windings. The series exciter windings includes two coils. In a high Y connection of the winding, the two coils are connected in series with each other and with the main phase winding. In the low voltage Y connection, series coils are separated and each is located in a paralleled leg of the same main phase winding. The shunt winding is connected directly across a corresponding main phase winding. An electronic voltage regulator includes phase voltage sensing which is coupled to a reference control circuit to produce a control signal if the voltage varies from a reference voltage. The current to the shunt winding of the exciter is controlled to maintain the desired output voltage.
    Type: Grant
    Filed: February 16, 1994
    Date of Patent: February 3, 1998
    Assignee: Marathon Electric Mfg. Corp.
    Inventor: William B. Dittman
  • Patent number: 5694027
    Abstract: On a stator core, there are wound T-connection primary generating windings such that the second and third single-phase windings are respectively arranged at positions electrically orthogonal to the first single-phase winding. The winding number of the first single-phase winding is 31/2 times that of the second single-phase winding or the third single-phase winding. The stator excitation windings are also wound on the stator core, which are connected to the center taps of the primary generating windings through a control rectifier. A plurality of field windings are wound on a rotor core. The field windings are arranged at positions where they are magnetically coupled with both the odd-order spatial higher harmonic components of armature reaction magnetic fields produced by currents flowing in the primary generating windings and the static magnetic fields produced by current flowing in the stator excitation windings.
    Type: Grant
    Filed: December 8, 1995
    Date of Patent: December 2, 1997
    Assignee: Satake Corporation
    Inventors: Satoru Satake, Kenji Inoue, Yukio Onogi, Hideo Yamashita, Yukio Hosaka
  • Patent number: 5598091
    Abstract: On a stator core, there are wound primary generating windings of four (4) poles with a distributed full-pitch winding structure and stator excitation windings with a concentrated full-pitch winding structure, having the number of poles odd-number times the number of poles of the primary generating windings, that is, twelve (12) poles. The primary windings appropriately produce spatial higher harmonic components of the armature reaction magnetic fields. The excitation windings are connected to the center taps of the primary windings through a control rectifier. On a rotor core, six field windings of four poles. The field windings are arranged at positions where they are magnetically coupled with both static magnetic fields produced by the stator excitation windings and odd-order spatial higher harmonic components of armature reaction magnetic fields produced by the currents in the primary generating windings. The field windings are short-circuited by the diodes, respectively.
    Type: Grant
    Filed: August 10, 1995
    Date of Patent: January 28, 1997
    Assignee: Satake Corporation
    Inventors: Satoru Satake, Yukio Hosaka, Yukio Onogi, Kenji Inoue
  • Patent number: 5187426
    Abstract: An arrangement for limiting the terminal voltage in an alternator has a fixed stator winding acting on rectifiers and an excitation winding which rotates with the alternator rotor. The arrangement also has a controller and a first slip ring contact which load the excitation winding with excitation current as a function of the magnitude of a delivered voltage, and at least one free-wheeling valve which is conductive during a controller-side interruption of the excitation current and is connected in parallel with the excitation winding. The arrangement includes an auxiliary winding on the rotor. The auxiliary winding continues the excitation winding in the same direction of winding, with the auxiliary winding and the excitation winding being connected at a first connection point. A second slip ring contact operatively connects the first connection point to a machine terminal supplying excitation current.
    Type: Grant
    Filed: April 17, 1991
    Date of Patent: February 16, 1993
    Assignee: Mercedes-Benz AG
    Inventors: Manfred Maass, Joachim Bunke, Martin Fritz
  • Patent number: 5051640
    Abstract: A stator-excited synchronous machine with an unwound, toothed rotor has a stator which is subdivided into sectors each of which is wound with an excitation winding. Permanent magnets are disposed between the stator sectors tangentially. The permanent magnets' magnetic fields in the stator sector yokes are directed in the circumferential direction, opposite to those of the adjoining excitation windings.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: September 24, 1991
    Assignee: Siemens Aktiengesellschaft
    Inventor: Werner Freise
  • Patent number: 4887020
    Abstract: A self-excited brushless alternator having a rotating field winding excited by an alternating current exciter whose rotating armature rotates with the rotating field winding and is permanently connected to the field winding via a field rectifier also mounted to rotate with the field winding. The exciter has an exciter stator primary winding and a rotary exciter secondary winding connected via a rotray field rectifier to the rotary main field winding of the alternator. The primary excitation for the exciter is derived, via magnetic coupling, from a rotary auxiliary magnetic field produced by a feedback winding in series with the main field winding and rotating herewith. A common magnetic circuit couples the rotary feedback winding with an auxiliary stator secondary winding and the exciter primary and secondary windings.
    Type: Grant
    Filed: October 27, 1987
    Date of Patent: December 12, 1989
    Assignee: U.S. Philips Corporation
    Inventor: Gary R. Graham
  • Patent number: 4871960
    Abstract: An output voltage control system for an electric generator having two field windings, wherein a rotary shaft of the generator is rotated by a power source such as an engine, for producing an output voltage. According to the invention, the control system includes a first control unit for supplying an electric current inversely proportionate to the output frequency of the generator to one of the field windings of the generator to produce a substantially constant output voltage for a stationay (fixed) load, and a second control unit for supplying an electric current derived from a portion of the output voltage produced at the generator output to the other of the field windings of the generator in the event of fluctuations in the generator load.
    Type: Grant
    Filed: August 2, 1988
    Date of Patent: October 3, 1989
    Assignee: Tamagawa Seiki Kabushiki Kaisha
    Inventor: Sadamitsu Yoden
  • Patent number: 4851758
    Abstract: A brushless generator having a rotor for generating a magnetic field, a stator having magnetic poles facing the rotor a main generating winding; and a voltage is induced as the magnetic field generated in the rotor intersects the main generating winding, in which slots are provided at the locations of the stator magnetic poles facing the rotor, exciting windings are wound on the slots to generate in the exciting windings voltages having different phases with respect to that of the voltage generated in the main generating winding, and brushes are eliminated by using the voltages generated in the exciting windings.
    Type: Grant
    Filed: March 3, 1988
    Date of Patent: July 25, 1989
    Assignee: Sawafuji Electric Co., Ltd.
    Inventors: Masahiro Osada, Toshihiko Tanuma, Takashi Yoshida, Hiroshi Kobiyama
  • Patent number: 4733157
    Abstract: A voltage regulator supplies excitation current both in addition and in subtraction, since supplied current can vary not only in intensity, but also in direction depending on the signal given by a control device, which regulates the conduction of the regulator both as far as intensity and direction are concerned, according to a comparison between a reference voltage and the voltage of the alternator itself, or, in any case, a part of it (123), said addition or subtraction been performed by electric or magnetic means. According to a preferred form of execution, the electronic device has bidirectional conditions consisting of a TRIAC (210) which feeds an auxiliary winding in one direction or the other; the TRIAC is triggered, in turn, by a control circuit which sends out a triggering signal being in relation to the voltage of the alternator and to a reference voltage.The TRIAC can be replaced by two controlled diodes or by two transistors or similar means, being connected to each other in inverted parallel.
    Type: Grant
    Filed: December 12, 1985
    Date of Patent: March 22, 1988
    Assignee: M.E.C.C. Alte S.p.a.
    Inventor: Luigi Malesani
  • Patent number: 4723106
    Abstract: A brushless generator exciter employs a hybrid full-wave rectifier in which at least some of the rectifying diodes are controllable according to an external signal for adjusting the total exciter power fed to the generator rotor. An optical transmission technique is employed for communicating gate and sync signals between stationary and rotating components.
    Type: Grant
    Filed: August 29, 1986
    Date of Patent: February 2, 1988
    Assignee: General Electric Company
    Inventors: Irving A. Gibbs, John H. Parslow, Andrew J. Galish
  • Patent number: 4663582
    Abstract: A stator is formed with two opposed magnetic poles, and first and second magnetic paths juxtaposed to each other. An output coil and a first exciting coil are wound on the first magnetic path in such a manner as to produce respective electromagnetic forces in the same phase. A second exciting coil is wound on the second magnetic path in such a manner as to produce an electromotive force in the same phase with the electromotive force produced by the first exciting coil. The first and second exciting coils supply exciting current to a field coil wound on a rotor arranged between the opposed magnetic poles during rotation of the rotor.
    Type: Grant
    Filed: April 16, 1985
    Date of Patent: May 5, 1987
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Shigeru Fujii, Motohiro Shimizu
  • Patent number: 4633160
    Abstract: A self-excited brushless alternator having a rotating field excited by an alternating current exciter whose armature rotates with the field winding of the alternator and is permanently connected to that winding by a rotating field rectifier. To obtain reliable regulation over a wind range of load and power factors, at least one exciter stator primary winding is magnetically coupled to at least one exciter rotator secondary winding which is connected by the rectifier to the main field. Primary excitation direct current for the exciter is derived by a magnetic coupling from a rotary auxiliary magnetic field produced by a feedback winding connected in series with the main field winding and rotating therewith. Preferably, current paths for the exciter primary excitation are different during and after build-up.
    Type: Grant
    Filed: January 25, 1985
    Date of Patent: December 30, 1986
    Assignee: U.S. Philips Corporation
    Inventor: Gary Graham
  • Patent number: 4467267
    Abstract: An excitation system for a brushless synchronous alternator includes an exciter having a stator which includes first and second sets of field coils respectively coupled to a source of DC power and in series with polyphase AC output current developed by the main generator. A base level of exciter field current is provided by the DC current delivered to the first set of field coils while a second variable amount of field current is provided by the AC output current delivered to the second set of field coils. The exciter also includes a rotor structure having first and second sets of armature windings which develop first and second exciter currents in response to movement of the rotor structure within the magnetic fields set up by the first and second sets of exciter field coils. The first and second exciter currents are added, rectified and delivered to a set of main generator field windings.
    Type: Grant
    Filed: January 28, 1983
    Date of Patent: August 21, 1984
    Assignee: Sundstrand Corporation
    Inventors: David J. Hucker, Norbert L. Schmitz
  • Patent number: 4424478
    Abstract: A device for exciting a master generator of self-contained power units for transportation facilities comprises a master generator with a first excitation winding, an auxiliary exciter generator with a second excitation winding, an exciting current regulator, and an independent d-c source. One of the leads of the first excitation winding of the master generator is electrically coupled to a respective d-c lead of the auxiliary exciter generator through its second excitation winding connected accordantly in series with the first excitation winding of the master generator.
    Type: Grant
    Filed: January 7, 1981
    Date of Patent: January 3, 1984
    Inventors: Eliazar Y. Bukhshtaber, Jury M. Andreev, Mikhail P. Askinazi, Anatoly D. Mashikhin, Egor P. Plotnikov, Vitaly I. Anders
  • Patent number: 4408152
    Abstract: A substantially constant frequency self-regulated generator produces in one embodiment 120 volts or the like single phase output or in another embodiment 120 or 240 volts or the like single phase output. The generator employs an exciter stator and a stationary rectifier assembly with the former being a six pole exciter stator alternately wound with three shunt poles and three series poles with two separate windings on each series pole. The three shunt poles of the exciter stator are connected in series making, in effect, one shunt winding. The series circuit consists of two separate windings on each series pole, which are respectively parallel connected and wound on all three series poles. Each series pole then has two separate isolated coils. With the exciter stator there is employed a stationary diode assembly utilizing three diodes as rectifiers for the shunt and isolated series windings.
    Type: Grant
    Filed: June 22, 1981
    Date of Patent: October 4, 1983
    Assignee: The Lima Electric Co., Inc.
    Inventors: Andrew F. Szippl, Robert B. Walker
  • 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: 4383215
    Abstract: To prevent over-excitation upon high-speed operation of a compound wound alternator, the shunt field, connected in standard manner to a voltage regulator, has an additional shunt field winding placed on the core, the additional shunt field winding being controlled from the output of the alternator and generating a magnetic field counter the field due to the compound winding if an auxiliary counter field voltage regulator senses that the output voltage of the alternator rises above a predetermined value.
    Type: Grant
    Filed: July 30, 1981
    Date of Patent: May 10, 1983
    Assignee: Robert Bosch GmbH
    Inventor: Manfred Frister
  • Patent number: 4354150
    Abstract: A slip ring less, three-phase, AC generator especially for motor vehicles, in which the compound winding is subdivided into individual components which are directly interconnected within the branches of the rectifier bridge supplying direct current for the on-board electrical system so that the voltage drop across the compound winding is sensed and compensated by the regulator. The compound winding can be wound of wire having a small diameter.
    Type: Grant
    Filed: April 16, 1980
    Date of Patent: October 12, 1982
    Assignee: Robert Bosch GmbH
    Inventor: Wolfgang Kofink
  • Patent number: 4336486
    Abstract: For a dynamoelectric machine, excitation power is supplied by a main exciter having two field windings. A first field winding is driven by a pilot exciter which supplies base excitation (small signal) for the main exciter. Forcing excitation (large signal) is supplied by the second field winding which is driven by an external, supplemental power source. The main exciter can thus provide the appropriate excitation for both normal and transient operating conditions. In addition, by switching the controlled rectifier elements associated with the supplemental power source, the second field winding is also capable of providing fast de-excitation for the main exciter.
    Type: Grant
    Filed: January 9, 1980
    Date of Patent: June 22, 1982
    Assignee: Westinghouse Electric Corp.
    Inventors: Dale I. Gorden, Sigrud R. Petersen
  • Patent number: 4233555
    Abstract: The stator windings of a dynamo electric machine include three phase and single phase output windings for generating alternating current output power at different voltages. The machine output voltage is kept relatively constant by means of a brushless exciter having control and compounding field windings which are energized through stationary rectifier circuits. The rectifier circuit for energizing the field windings of the exciter is connected to or near the neutral leads of the stator windings to maintain a low voltage between the diodes of the rectifier and ground. The energization of the compounding field winding is controlled by means of a variable resistor in dependence upon whether the load connected to the dynamo electric machine is supplied with single phase or three phase current.
    Type: Grant
    Filed: April 5, 1979
    Date of Patent: November 11, 1980
    Assignee: Dyna Technology, Inc.
    Inventor: Lawrence R. Roche
  • Patent number: 4117388
    Abstract: A dynamo electric machine including an alternating current generator and a brushless exciter for the generator field, wherein control and compounding field windings of the exciter are energized from the generator stator winding through stationary rectifier circuits, the rectifier circuit for the compounding field making connection with the generator stator winding in the vicinity of its neutral point to avoid impressing high voltage to ground on rectifiers of the circuit.
    Type: Grant
    Filed: January 7, 1977
    Date of Patent: September 26, 1978
    Assignee: Dyna Technology, Inc.
    Inventor: Lawrence R. Roche
  • Patent number: 4105963
    Abstract: A brushless welding generator with a homopolar machine which supplies welding current, and has winding-free rotors with several pole rings. Each of these form an air gap of varying size around its periphery with the stator. The homopolar machine is divided into two electromagnetic parts, each having an exciting winding. The exciting field is controlled in one of the two electromagnetic parts in opposition to the welding current. One electromagnetic part, furthermore, has a further exciting winding fed by the welding current to control its exciting field. This further exciting winding produces an exciting field directed opposite to the exciting field of the first-mentioned exciting winding. A regulator controls the welding current of one exciting winding, and a signal derived from the welding current is applied to the regulator for representing an actual value.
    Type: Grant
    Filed: June 2, 1977
    Date of Patent: August 8, 1978
    Assignee: J. U. W. Muller, Maschinen-und Armaturenfabrik GmbH
    Inventor: Aurel Dobranis
  • Patent number: 4004211
    Abstract: In a compound AC generator having at least one pair of magnetic poles, series field windings wound on the magnetic poles, respectively, and at least one shunt field winding wound on at least one of the pair of magnetic poles in layers with the series field winding wound thereon, the series field winding wound in layers with the shunt field winding is associated with means for blocking the current flow through the series field winding in a direction to increase the magnetic fluxes through the associated magnetic pole thereby to minimize the effects of pulsating field current through the shunt field winding and to stabilize the output of the generator.
    Type: Grant
    Filed: February 3, 1976
    Date of Patent: January 18, 1977
    Assignee: Hitachi, Ltd.
    Inventors: Masaki Takao, Hideo Tatsumi