Electric Motor Control Patents (Class 322/39)
  • Patent number: 11575248
    Abstract: A prefabricated substation is provided with a solid state breaker and a transformer. The substation preferably transforms voltage from a medium voltage to a low voltage. The substation also breaks current flow through the substation when a fault occurs. The primary components of the substation, including the transformer and solid state breaker, are located together within the housing.
    Type: Grant
    Filed: December 31, 2019
    Date of Patent: February 7, 2023
    Assignee: ABB SCHWEIZ AG
    Inventors: Taosha Jiang, Carlos David Nieto, Debrup Das, Daniel Turk
  • Patent number: 11476787
    Abstract: An inverter type engine generator includes an alternator; and a converter composed of the a three-phase rectifying bridge circuit including an upper and lower three sets of elements, and converting three-phase alternating current output from the alternator into direct current. The upper and lower three sets of elements of the three-phase rectifying bridge circuit of the converter are configured such that upper elements are configured at least from duty-controllable diode elements, and lower elements are configured at least from duty-controllable switching elements having diodes.
    Type: Grant
    Filed: August 31, 2018
    Date of Patent: October 18, 2022
    Assignee: Honda Motor Co., Ltd.
    Inventors: Minoru Maedako, Toshio Inoue
  • Patent number: 10000296
    Abstract: An example aircraft electrical system includes a generator coupled with a gas turbine engine and a controller operable to distribute power of the generator. The controller includes a first control module positioned at a first location remote from the generator and a second control module positioned at a second location proximate the generator. The first control module is configured to verify at least one output of the generator, detect a fault condition of the generator, and control operation of at least one power bus in communication with the first control module. The second control module is configured to regulate the at least one output of the generator, where the at least one output includes a voltage. An example method of operating an electrical system is also disclosed.
    Type: Grant
    Filed: February 18, 2015
    Date of Patent: June 19, 2018
    Assignee: HAMILTON SUNDSTRAND CORPORATION
    Inventors: Mark J. Seger, Wes Ralph, Lon R. Hoegberg, Robert A. Bayles, Sunil S. Patel
  • Patent number: 9002761
    Abstract: A system, method and apparatus for automatically adapting power grid usage by controlling internal and/or external power-related assets of one or more users in response to power regulation and/or frequency regulation functions in a manner beneficial to both the power grid itself and the users of the power grid.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: April 7, 2015
    Inventor: Rey Montalvo
  • Patent number: 8823334
    Abstract: A method for starting an electric motor, the motor having a main machine, exciter, and permanent magnet generator (PMG), each having a stator and a rotor, with each rotor mounted to a common shaft, the method comprising starting the main machine in an asynchronous mode by applying a starting current to the stator of the main machine to induce a damper current in a damper winding of the main rotor to generate a starting torque that initiates the rotation of the common shaft, and then running the main machine in synchronous mode by supplying running current from the exciter rotor to the main machine rotor.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: September 2, 2014
    Assignee: GE Aviation Systems LLC
    Inventors: Hao Huang, Xiaochuan Jia
  • Publication number: 20140049229
    Abstract: A power generation unit driver, a power generation unit and energy output equipment in a power grid are described. The power generation unit driver includes a drive controller for generating a drive signal according to a first control signal and a second control signal obtained thereby, a converter for transforming the input energy from a first voltage into a second voltage according to the drive signal and outputting the same to an electric motor connected to the power generation unit driver. The first control signal runs condition information of the electric motor, and the second control signal includes the power grid frequency and/or the voltage amplitude of the power grid. The concept produces improved effects on the stability of power supply by a power grid.
    Type: Application
    Filed: March 9, 2012
    Publication date: February 20, 2014
    Applicant: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Jing Li, Hua Liao, Xin Hua Liu, Jing Wei Zhang
  • Patent number: 8405344
    Abstract: A method is disclosed for estimating a rotation speed of an electric motor supplied by an inverter, by determining a time derivative of a stator current vector of the electric motor during a zero vector state of the inverter; and determining an estimate of the rotation speed of the electric motor on the basis of the determined time derivative of the stator current vector.
    Type: Grant
    Filed: November 12, 2009
    Date of Patent: March 26, 2013
    Assignee: ABB Oy
    Inventor: Samuli Heikkilä
  • Publication number: 20120235648
    Abstract: A generator includes a rotor structure has a rotor frame that supports a rotor circuit. The rotor frame is electrically connected to the rotor circuit via a resistive element.
    Type: Application
    Filed: March 18, 2011
    Publication date: September 20, 2012
    Inventors: Nathan A. Berry, Philip Gillingwater
  • Patent number: 8154260
    Abstract: Within generator systems maintenance of stability in terms of voltage is desirable. Generally, several generators will be arranged in parallel within the generator system with one generator voltage controlled to provide dynamic responsiveness to load switching. With regard to some loads which are generally of an active nature, the capacity of a first generator, which is voltage controlled, may be insufficient to adequately avoid transient voltage instability. By providing an actuator signal from a load to act as a pre-emptive or forward feed to an electrical current controlled generator, that second electrical current generator can be arranged to provide additional or reduced electrical current to avoid system voltage instability.
    Type: Grant
    Filed: March 16, 2009
    Date of Patent: April 10, 2012
    Assignee: Rolls-Royce PLC
    Inventors: Lihua Hu, David R Trainer, Stephen A Long
  • Publication number: 20120074912
    Abstract: A control circuit (microcomputer) is provided in each of two inverter portions. Magnitude of a target waveform signal corresponding to a voltage to be output by each of the inverter portions is varied according to an operation state. The number of revolution of the engine is adjusted according to the larger one of the effective powers output from the two inverter portions. To cope with a temporary output shortage from the AC generator, the output voltage is temporarily lowered and then the output voltage is restored after waiting for the number of revolution of the engine increases.
    Type: Application
    Filed: October 27, 2009
    Publication date: March 29, 2012
    Applicants: YANMAR CO., LTD., SAWAFUJI ELECTRIC CO., LTD.
    Inventors: Masao Namai, Toru Yoshioka, Shinichi Azuma, Yukio Karasawa, Shinji Hibi, Takashi Abe
  • Patent number: 8111502
    Abstract: An arrangement related to subsea electric power distributing AC-system and adapted for a subsea application. The arrangement is enclosed in a watertight casing. The casing exposes a main power input connection, adapted for watertight co-ordination with a first subsea cable and a main power output connection, adapted for a watertight co-ordination with a second subsea cable. The second subsea cable is adapted for a power supply to an AC-current and AC-voltage adapted device. The arrangement includes interconnected: a voltage regulator connected to the first cable, and a NO-load switching unit connected to the second cable, and a control unit. The control unit is adapted, in a first operative mode, to regulate the output AC-voltage from the voltage regulator towards and to zero, or at least almost to zero, and in a second subsequent operative mode, to bring the NO-load switching unit from an ON-position to an OFF-position or vice versa.
    Type: Grant
    Filed: July 2, 2008
    Date of Patent: February 7, 2012
    Assignee: Vetco Gray Scandinavia AS
    Inventor: Svend Rocke
  • Patent number: 7884580
    Abstract: The present invention relates to a constant-power brushless DC motor and a generator using the same, and in particular, to a constant-power brushless DC motor and a generator using the same, which stably generates power upon load fluctuation. Since the stator is wound in parallel by phases and poles, the motor is realized to generate high power with low voltage and since the stator's winding is performed without interconnection, automatic production is realized to reduce costs and enable mass production. Accordingly, a generator constituted by using the above-described motor supplies high efficient power.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: February 8, 2011
    Inventor: Oak-Jae Lee
  • Publication number: 20090322084
    Abstract: Energy systems, energy devices, energy utilization methods, and energy transfer methods are described. In one arrangement, energy utilization methods include providing first energy from a power grid to an induction generator at a first moment in time; using the induction generator and the first energy from the power grid, charging an energy storage device; using second energy from the energy storage device, powering a motor causing the induction generator to generate third energy during a second moment in time; and providing the third energy to the power grid. Other arrangements are described.
    Type: Application
    Filed: June 30, 2008
    Publication date: December 31, 2009
    Inventor: Scott Robert Hamilton
  • Publication number: 20090251113
    Abstract: A system for cordless transfer of power for appliances or electronic devices 30 has a power transferring device 80 with a plurality of magnets 52 driven by a motor 70B powered by commercial electric power devices or lines. The power transferring device 80 is positioned below a table or countertop 20. On the undersurface of each appliance or electronic device 30 are one or more circular rotating magnetic arrangements 52 with opposing (attraction) poles to drive a dynamo 40 or dynamos. When the motor 70B is switched on, the drive axle 72 rotates a support base 82 upon which a plurality of magnets 52 is attached about an axis which correspondingly moves the plurality of magnets 52 in a circular motion creating a rotating magnetic field 50 to turn the dynamo 40 inside the base of the cordless appliance or electronic device 30.
    Type: Application
    Filed: April 2, 2008
    Publication date: October 8, 2009
    Inventor: Puthalath Koroth Raghuprasad
  • Patent number: 7580777
    Abstract: An aircraft system for control of the application of power to a plurality of devices in the aircraft comprises a plurality of local control modules. Each local control module controls the application of the power to the group of at least one device. A central control system communicates with and controls the local control modules.
    Type: Grant
    Filed: July 28, 2006
    Date of Patent: August 25, 2009
    Assignee: Ultra Electronics Limited
    Inventors: Timothy Smith, James Daas
  • Publication number: 20080218131
    Abstract: A generator without emissions that portably temporarily and quietly is capable of producing electrical power for household appliances in the event of a blackout. The generator has a power source such as a battery and on/off switch operably connected to an electrical motor. The motor is connected to an alternator that is operably connected to at least one outlet. The generator is contained in a housing that may be moved by the user.
    Type: Application
    Filed: February 27, 2008
    Publication date: September 11, 2008
    Inventors: Teodoro Rivera, Carlos A. Rivera, Jose R. Rivera, Marco A. Rivera
  • Patent number: 7342382
    Abstract: The present invention is directed to determining and controlling the appropriate moment at which a combined starter/alternator should transition from start-up mode to alternator/generator mode following an IC engine start-up sequence. The method relies on battery voltage or battery current monitoring to establish the timing of the transition.
    Type: Grant
    Filed: February 3, 2004
    Date of Patent: March 11, 2008
    Assignee: Dana Corporation
    Inventors: Scott Evart Blackburn, Eric Keith Manning
  • Patent number: 7292011
    Abstract: A generator system includes a generator control for providing electrical power to a main generator. The main generator is mechanically coupled to an electrical power source that provides electrical power to the generator control during operation of the main generator. An arc fault device in electrical communication with the electrical power source electrically isolates the power source from the generator control when an arc fault within the generator control is detected.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: November 6, 2007
    Assignee: Hamilton Sundstrand Corporation
    Inventor: Bruce D. Beneditz
  • Patent number: 7174731
    Abstract: This invention relates to a rotational speed control system including a plurality of motor drivers for driving motors, and the object thereof is to drive a plurality of motors at the same rotational speed without depending on the number of motor drivers and without depending on the characteristics of each motor driver. A remote controller 31 and a motor driver 202 are connected to a motor driver 201. The motor drivers 201 and 202 control motors M11 and M12 at a prescribed rotational speed, respectively. A rotational speed instructing signal 91 indicative of the rotational speed is supplied from the remote controller 31 to the motor driver 201, and further supplied from the motor driver 201 to the motor driver 202. Because the rotational speed instructing signal 91 indicates a rotational speed which is transmitted in a digital value between the motor drivers 201 and 202, both of the motors M11 and M12 are driven at the rotational speed indicated by the rotational speed instructing signal 91.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: February 13, 2007
    Assignee: Daikin Industries, Ltd.
    Inventor: Takashi Okano
  • Patent number: 6949902
    Abstract: A controller of a rotating electric machine for a vehicle has a magnetic field electric current command arithmetic device for commanding a magnetic field electric current by the command of a torque and electric power command arithmetic device, an electric power converter functioning as a rectifier or an inverter, and a magnetic field electric current command restraining device for restraining a three-phase line electric current by restraining and controlling an output of the magnetic field electric current command arithmetic device when the rotating electric machine functions as an electric generator.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: September 27, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masakazu Nakayama, Masaru Kobayashi, Masato Mori, Kiyoharu Anzai
  • 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: 6781331
    Abstract: A method and system of regulating an output voltage of a boiling water reactor nuclear reactor plant recirculation system motor generator are provided. The method includes sensing an alternator output voltage and transmitting an alternator output voltage signal to a voltage regulator circuit, sensing an alternator speed and transmitting an alternator speed signal to the voltage regulator circuit, comparing the alternator output voltage signal to the alternator speed signal with a volts per hertz divider network electrically coupled to the alternator output voltage sensing circuit and the alternator speed sensing device, adjusting a capacitive reactance of the voltage regulator with a lead compensation circuit electrically coupled in series with the volts per hertz divider network, and adjusting a current in a control winding of a saturable reactor.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: August 24, 2004
    Assignee: General Electric Company
    Inventors: James Steven Mokri, Nelso Petroni, William Michael Steiner, Stephen L. Joslin, Craig Ernest Leighty
  • Patent number: 6768277
    Abstract: In a gas turbine system having first power converter converting power system N AC voltage to DC voltage, second power converter converting the DC voltage into AC voltage, generator connected to second power converter's AC output and rotated by turbine and turbine controller outputting a revolution speed command value omg* according to a fuel flow rate of the turbine, a detector for detects a revolution speed omg of the generator, another detector detects Vdc of the first converter, a speed regulator generats a DC voltage command value according to a difference between omg and omg*, a switchover unit selects either a preset DC voltage command value Vref or the DC voltage command value according to the revolution speed omg and a voltage regulator and a controller control first power converter conversion output according to a control signal for making Vdc coincide with Vdc*.
    Type: Grant
    Filed: March 18, 2002
    Date of Patent: July 27, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Masaya Ichinose, Motoo Futami, Hiroshi Arita
  • Patent number: 6710581
    Abstract: A constant-power brushless DC motor is provided, including a stator which is wound in parallel by phases and polarities and configured of n multi-phases, a rotor having a predetermined number of polarities, which is required to concentrate magnetic flux on its area, a commutation encoder including sensing regions and nonsensing regions, and two photo sensors set to each phase, the two photo sensors being connected to a controller, to excite only (n-b) phases among n phases, starting and rotating the motor, thereby realizing a constant-power DC motor without commutator, which is effective in energy saving, has good characteristic of continuous speed conversion and compact configuration.
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: March 23, 2004
    Assignee: I.S. Motor Korea Co., Ltd.
    Inventor: I Soo Lee
  • Patent number: 6552515
    Abstract: The performance of a generator is improved in a higher range of the output by correcting a decrease in the average direct current voltage supplied to an inverter. An average calculator calculates an average of direct current voltage inputs to the inverter for comparing with a target voltage (level) VDC. When it is judged by an average voltage deviation detector that the average is smaller by a specific amount than the target voltage level, the target voltage level is increased by an adjusting unit. A conductor angle setting unit determines the conduction angle of thyristors to change the voltage input of the inverter to an adjusted target voltage level VDCm. A thyristor drive circuit controls the conduction of the thyristors in the converter according to the conduction angle.
    Type: Grant
    Filed: December 3, 2001
    Date of Patent: April 22, 2003
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Motohiro Shimizu, Masashi Nakamura
  • Patent number: 6490511
    Abstract: A torque based monitor method, apparatus, and system, for a torque splitting hybrid electric vehicle (HEV) powertrain and regenerative brake 54 system. The preferred powertrain configuration includes an internal combustion engine 20, generator 32, and electric traction motor 36 combined to produce the vehicle's output shaft torque. The invention has a set of vehicle state sensors and communication interfaces connected independently to a main controller 200 and an independent plausibility check (IPC) 202. The IPC monitors and mitigates the powertrain output shaft torque (OST) by reducing powertrain torque when the detected OST is greater than the desired OST. The IPC has a second mode of operation to shut down the powertrain OST of the HEV powertrain when a fault or failure is detected. Additional features include a quizzer 204 function to continuously verify the functionality of the IPC.
    Type: Grant
    Filed: November 10, 2000
    Date of Patent: December 3, 2002
    Assignee: Ford Motor Company
    Inventors: Abbas Raftari, Deepa Ramaswamy, Jerry D. Robichaux
  • Patent number: 6429613
    Abstract: A generation control device of a hybrid electric vehicle is able to satisfactorily generate power with an excellent responsiveness with respect to a high output requirement from a motor. If a charge level SOC sensed by a charge level sensing device is not greater than a generation start value SOCsta, a generator starts a normal output generation (P(G)=P1). The normal output generation is continued until the charge level SOC reaches a generation end value SOCend larger than the generation start value SOCsta. If a required power consumption Pm of a traction motor sensed by a required power consumption sensing device is not less than Ph, a high output generation (P(G)=P2) with a higher output than the normal output generation is executed instead of the normal output generation.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: August 6, 2002
    Assignee: Mitsubishi Jidosha Kogyo Kabushiki Kaisha
    Inventors: Takashi Yanase, Makoto Ogata
  • Patent number: 6177738
    Abstract: An electrical system for use in isolation, the electrical system comprising a main engine (14), such as a gas turbine or a diesel engine, a generator (13) driven by the main engine (14) for generating a first alternating voltage (19), a first rectifier unit (12) for converting the first alternating voltage (19) generated by the generator (13) into a direct voltage on a DC bus (18), and at least one inverter unit (10, 15) for converting the direct voltage of the DC bus (18) into a second alternating voltage (20). The generator (13) driven by the main engine (14) for generating the first alternating voltage (19) is an asynchronous machine coupled directly to the shaft of the main engine (14), and the first rectifier unit (12) also comprises an inverter part for converting the direct voltage of the DC bus (18) into an alternating voltage with an adjustable frequency to said asynchronous machine (13) so as to use the machine as a motor.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: January 23, 2001
    Assignee: ABB Industry Oy
    Inventors: Erkki Hentunen, Tero Multanen
  • Patent number: 5804947
    Abstract: A generator controller used in hybrid electric vehicle. The battery current is sampled and accumulated for T seconds. The obtained accumulated value is used to determine the control target of the generated power. Since the generated power is controlled according to the accumulated current of the battery which fits the battery's characteristic compared to the charged-and-discharged power, the battery's state of charge (SOC) can be more accurately controlled within the target zone. When the SOC of the battery is initially outside the target zone, the SOC is adjusted within the target zone by forcibly discharging or charging the battery. The precision of SOC control can be improved compared to when the SOC of the battery is controlled using the charged-and-discharged power.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: September 8, 1998
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Yoshihide Nii, Nobuyuki Taki
  • Patent number: 5654624
    Abstract: The invention relates to a method of starting an asynchronous machine irrespective of whether the rotor of the machine is rotating or not when the machine is supplied by an inverter provided with a separate moment and flux or moment and magnetizing current control, which is faster than the time constants of the asynchronous machine. According to the invention, zero moment is set as a target for the control, a voltage is supplied to the stator of the machine by the inverter, a stator current vector and a stator flux generated by the voltage is determined, an estimate of that vector or some other quantity comparable to the stator flux is determined, a moment caused by the stator flux vector and the stator current vector is determined and information of the moment is supplied to the control, which tries to zero the caused moment by making the stator flux and a rotor flux generated thereby cophasal, thus synchronizing the supply frequency of the inverter with a possible rotation of the machine rotor.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: August 5, 1997
    Assignee: ABB Industry OY
    Inventor: Petri Schroderus
  • Patent number: 5543703
    Abstract: A vehicular generator motor performing generator operation and motor operation is disclosed. The generator motor comprises an AC-DC converter means and a switching means. The converter means is composed of a plurality of MOSFETs and connected between each armature coil and a vehicular storage battery. Alternating current produced across the coils is converted into a direct current for charging the battery by the AC-DC converter means in generator operation mode. In motor operation mode, the DC output from the battery is converted into an alternating current for setting up a rotating magnetic field by the converter means, and the battery output is fed to the armature coils. The mode of operation of the MOSFETs is switched between these two modes by the switching means. The rotating field produces a certain phase difference with the magnetic field developed by the rotating magnetic poles. The MOSFETs are made of SiC having a smaller resistivity than that of Si.
    Type: Grant
    Filed: December 23, 1994
    Date of Patent: August 6, 1996
    Assignee: Nippondenso Co., Ltd.
    Inventors: Shin Kusase, Kenzo Mitani, Atsushi Umeda, Norihito Tokura, Hirohide Sato
  • Patent number: 5519276
    Abstract: A DC compound motor of the type having a series winding and a shunt field winding includes an auxiliary generator driven by the motor for supplying power to the shunt field winding. The generator can be chosen, or a control circuit added, to control the current supply to the shunt field winding based on the speed of the motor.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: May 21, 1996
    Inventor: Tai-Her Yang
  • Patent number: 5504414
    Abstract: An electric system for an electric vehicle enabling a secondary battery to be charged easily without using a large capacity and bulky charging system. The system can maintain integrity of power on a distribution network during charging. When charging the secondary battery, a switch connecting an inverter to an AC motor is opened, and then, the AC voltage from an external distribution network is supplied to the AC side of the inverter. The inverter rectifies the AC voltage to a DC voltage under the control of a control circuit so that the secondary battery is charged by the DC voltage. In another example, the windings of the AC motor may be connected between the distribution network and the inverter by the switching operation of a three-pole contactor so that the windings function as AC reactors.
    Type: Grant
    Filed: January 28, 1993
    Date of Patent: April 2, 1996
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Shigenori Kinoshita
  • Patent number: 5369599
    Abstract: A performance measure of an ATR is made from ancillary target data and the ATR output. A parameter of the ATR is varied to determine the change an ATR performance due to the parameter variation. Separate performance in the form of a quadratic equation models provide performance as a function of parameter and metrics. The performance model is partially differentiated with respect to the parameter. The partial differentiation allows solution for the estimated metric.
    Type: Grant
    Filed: August 4, 1992
    Date of Patent: November 29, 1994
    Assignee: Honeywell Inc.
    Inventors: Firooz A. Sadjadi, Mike E. Bazakos, Hatem Nasr
  • Patent number: 4806841
    Abstract: An output frequency control circuit is mounted on the rotating shaft connecting a motor and generator. The motor-generator system includes exciter circuits, an input power factor control and an output voltage regulator. The input power factor control ensures that the motor input power factor is unity, which is desirable for motor control. The frequency control circuit responds to variations in the AC power source frequency by generating low frequency excitation to boost or buck the operational speed of the machine, causing the generator output frequency to remain constant at a selected frequency output irrespective of input power source frequency variation. The output frequency may be selected over a given range from a control panel adjustment pot.The major innovation is that the entire frequency control circuit is shaft-mounted and requires no slip-rings or magnetic transformers for signal transfer, thus reducing the possibilities of mechanical failure.
    Type: Grant
    Filed: February 29, 1988
    Date of Patent: February 21, 1989
    Assignee: Teledyne Inet
    Inventors: Robert H. Lee, Alexander Levran
  • Patent number: 4575671
    Abstract: Methods and apparatus are disclosed for synchronizing multiple AC motor driven synchronous generators to the voltage on a common output bus. In one method, the rotating motor is disconnected from its AC power source, the generator voltage is phase synchronized to the output bus voltage, and then the generator rotor is caused to slip one generator pole at a time until the motor generated voltage is phase synchronized to the AC power source voltage. At that point, the motor is reconnected to the AC power source. Other methods are disclosed in which magnetic position sensors are employed to provide an indication of when the rotors on multiple motor driven generators are mechanically phase synchronized.
    Type: Grant
    Filed: February 14, 1984
    Date of Patent: March 11, 1986
    Assignee: Teledyne Industries, Inc.
    Inventors: Robert H. Lee, Suresh C. Gupta