With Line-drop Compensation Patents (Class 322/21)
  • Publication number: 20150137771
    Abstract: A power generation system includes a generator mechanically coupled to an engine to generate electrical power and a fault ride through system connected between the generator and a power grid. The fault ride through system includes a mechanical switch connected in parallel with a solid state switch and a controller for controlling the mechanical switch, the solid state switch and ignition of the engine in coordination.
    Type: Application
    Filed: November 20, 2013
    Publication date: May 21, 2015
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Ara Panosyan, Said Farouk Said El-Barbari, Stefan Schroeder
  • Publication number: 20150115902
    Abstract: A power generation system includes a generator mechanically coupled to an engine to generate electrical power and a fault ride through system connected between the generator and a power grid. The fault ride through system includes a mechanical switch connected in parallel with a solid state switch and a resistor to absorb power from the generator during a grid fault condition. The mechanical switch and the solid state switch are controlled in coordination with the engine.
    Type: Application
    Filed: October 29, 2013
    Publication date: April 30, 2015
    Applicant: General Electric Company
    Inventors: Ara Panosyan, Said Farouk Said El-Barbari, Stefan Schroeder
  • Publication number: 20150102782
    Abstract: A vehicle-mounted electric rotating machine includes a field winding wound on a rotor for magnetizing a field pole of the rotor, a stator winding for generating an AC voltage in accordance with a rotating magnetic field generated by the field pole, a power converter for converting the AC voltage to a DC voltage and outputting the DC voltage through a first power supply line connected to an output terminal thereof, and a load dump handling section for performing a load dump protection operation when a voltage of the output terminal of the power converter exceeds a threshold voltage. The load dump handling section is supplied with operating power through a second power supply line provided separately from the first power supply line.
    Type: Application
    Filed: October 15, 2014
    Publication date: April 16, 2015
    Inventors: Hideaki NAKAYAMA, Harumi HORIHATA
  • Publication number: 20150077067
    Abstract: This disclosure is directed to a fault-tolerant energy conversion system. A fault-tolerant doubly-fed induction generator (DFIG) for use with a wind energy conversion system (WECS) consistent with the present disclosure may allow for seamless operation during all kinds of grid faults. In one embodiment, a six-switch grid side converter (GSC) commonly used with such systems may be replaced with nine-switch converter circuitry. With three additional switches, the nine-switch converter can provide two independent three phase outputs. For example, one three-phase output may be coupled to the grid through interfacing inductors to realize normal GSC operation, while the other three-phase output may be coupled to neutral side of the stator windings to provide fault ride-through (FRT) capability to the DFIG. A control algorithm may be employed that both achieves seamless fault ride-through during any kind of grid faults and strictly satisfies grid codes requirements.
    Type: Application
    Filed: June 25, 2014
    Publication date: March 19, 2015
    Inventors: Parag Kanjiya, Bharath Ambati, Vinod Khadkikar
  • Publication number: 20150061298
    Abstract: An electromagnetic braking system includes an electrically conductive disc coupled to a rotatable shaft of a power generation system for operating in an island mode. The rotatable shaft is operatively coupled between a prime mover and a generator for supplying power to an island grid. The electromagnetic braking system further includes a controller for receiving at least one status or synchronization signal and for generating a control signal based on the at least one signal and an inducting unit for applying an electromagnetic braking force on the electrically conductive disc when commanded by the control signal to regulate a rotational speed of the rotatable shaft.
    Type: Application
    Filed: November 13, 2014
    Publication date: March 5, 2015
    Inventors: Ara Panosyan, Stefan Schroeder, Christoph Boeld, Herbert Schaumberger, Johann Hirzinger-Unterrainer, Xiaoting Dong, Uwe Liebscher
  • Publication number: 20150042293
    Abstract: An energy production plant has a drive train including a differential gear (14) with three drive and power take-off assemblies, a first drive assembly being connected to a drive shaft, a power take-off assembly being connected to a generator (13) and a second drive assembly being connected to a differential drive assembly (16). The differential gear (14) is a planetary gear. Both an emergency brake (4) and a service brake (20) are located in the drive train. In the event of a power failure, grid fault or an emergency shutdown, the service brake (20) is activated such that the torque acting on the rotor (1) supplied by the drive train remains substantially constant for a period of at least 0.5 seconds.
    Type: Application
    Filed: March 28, 2013
    Publication date: February 12, 2015
    Inventor: Gerald HEHENBERGER
  • Publication number: 20140333268
    Abstract: A braking system includes a converter, a capacitor coupled to an output of the converter, a bridge coupled in parallel to the capacitor, and at least one inductor coupled to the bridge, an electrically conductive disc disposed proximate to the at least one inductor, and a switching unit controller for commanding the converter to convert a level of voltage supplied therefrom from a first voltage level to a second voltage level and thereby increase energy stored in the capacitor, and, upon receiving a brake command, commanding the bridge to ramp-up electrical current in the at least one inductor so as to induce an electromagnetic force on the electrically conductive disc.
    Type: Application
    Filed: July 24, 2014
    Publication date: November 13, 2014
    Inventors: Stefan Schroeder, Ara Panosyan, Christoph Boeld, Herbert Schaumberger, Xiaoting Dong, Uwe Liebscher
  • Publication number: 20140239921
    Abstract: A load bank comprises one or more load resistors connected to an engine-generator and a control system for maintaining a minimum generator load when necessary for optimal operation. The control system operates the load bank to mitigate harmful effects of generator neglect and maintains loading for efficient DPF regeneration while allowing the generator to quickly dump the load bank when real load increases.
    Type: Application
    Filed: February 26, 2013
    Publication date: August 28, 2014
    Applicant: MULTIQUIP, INC.
    Inventor: MULTIQUIP, INC.
  • Patent number: 8816651
    Abstract: A load bank comprises one or more load resistors connected to an engine-generator and a control system for maintaining a minimum generator load when necessary for optimal operation. The control system operates the load bank to mitigate harmful effects of generator neglect and maintains loading for efficient DPF regeneration while allowing the generator to quickly dump the load bank when real load increases.
    Type: Grant
    Filed: February 26, 2013
    Date of Patent: August 26, 2014
    Assignee: Multiquip, Inc.
    Inventor: George Fell
  • Publication number: 20140138949
    Abstract: Fault Ride Through (FRT) transient management system configured to enhance the FRT capability doubly-fed induction generator (DFIG)-based wind turbines. A grid side converter (GSC) introduces shunt and series compensation for normal operation and voltage dips, respectively. A braking resistor may be added to smooth switching transients from shunt to series interfaces and dissipate excessive power from the GSC. To attain a flexible control solution for balanced and unbalanced fault conditions, the transient management scheme may employ positive and negative sequence controllers. The system dynamics for the series compensation topology may be analyzed using small-signal linear model. Based on the mathematical model, the controller may be tuned to balance voltage regulation performance and transient stability margins with consideration of various operating conditions.
    Type: Application
    Filed: April 24, 2013
    Publication date: May 22, 2014
    Applicant: Masdar Institute Of Science and Technology
    Inventor: Masdar Institute Of Science and Technology
  • Publication number: 20140077772
    Abstract: A turbine array including: a plurality of turbines; an electrical machine connected to each of the turbines and to an electrical grid; wherein at least one of the electrical machines is a motor-generator which can operate in a motor mode or a generator mode, and wherein the other electrical machines are generators; and a controller for detecting a loss-of-grid event; wherein the controller sets the motor-generator to the motor mode when a loss-of-grid event is detected, the motor-generator being driven by the generators and thereby providing a load to the generators.
    Type: Application
    Filed: April 18, 2012
    Publication date: March 20, 2014
    Applicant: ROLLS-ROYCE PLC
    Inventor: Adam P. Chir
  • Publication number: 20130334818
    Abstract: A braking system for a wind turbine is disclosed. The braking system may include a DC chopper connected to a DC bus and a super capacitor capable of being connected to the DC chopper through a switch. The DC chopper may be controlled by a control system to enable one of charging, discharging, idle or system off modes of the super capacitor.
    Type: Application
    Filed: June 19, 2012
    Publication date: December 19, 2013
    Applicant: Clipper Windpower, LLC.
    Inventors: Hanif Mashal, Souleman Njoya Motapon
  • Patent number: 8547071
    Abstract: In a rotary electric machine, a load-dump protector turns on a switching element as a low-side rectifying element for at least one of plural-phase stator windings when the output voltage exceeds a first threshold voltage due to load dump. The load dump protector determines a turnoff timing of the switching element as the low-side rectifying element for the at least one of the plural-phase stator windings after the output voltage, which exceeded the first threshold voltage once, falls below a second threshold voltage. The second threshold voltage is set to be lower than the first threshold voltage. The load dump protector turns off, at the determined turnoff timing, the switching element as the low-side rectifying element for the at least one of the at least two-phase stator windings.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: October 1, 2013
    Assignee: Denso Corporation
    Inventors: Harumi Horihata, Yoshihide Itoh, Hideaki Nakayama
  • Publication number: 20130249501
    Abstract: A double fed induction generator (DFIG) converter method are presented in which rotor side current spikes are attenuated using series-connected damping resistance in response to grid fault occurrences or grid fault clearances.
    Type: Application
    Filed: March 26, 2012
    Publication date: September 26, 2013
    Applicant: Rockwell Automation Technologies, Inc.
    Inventors: Haihui Lu, Zhenhuan Yuan, Lixiang Wei, Russel Kerkman, Richard Lukaszewski, Ahmed Mohamed Sayed Ahmed
  • Patent number: 8541988
    Abstract: A rectifying unit rectifies an alternating current voltage induced across each of at least two-phase stator windings. A turn-on unit monitors an output voltage of the rectifying unit, and turns on a switching element as a low-side rectifying element for at least one of the at least two-phase stator windings when the output voltage exceeds a first threshold voltage due to load dump. After the output voltage, which exceeded the first threshold voltage once, falls below a second threshold voltage, a turnoff unit waits for turnoff of the switching element until a turnoff time suited for preventing occurrence of a surge across the at least one of the at least two-phase stator windings appears. The second threshold voltage is set to be lower than the first threshold voltage. The turnoff unit turns off, at the appearance of the turnoff time, the switching element.
    Type: Grant
    Filed: July 8, 2011
    Date of Patent: September 24, 2013
    Assignee: Denso Corporation
    Inventors: Harumi Horihata, Tadatoshi Asada
  • Publication number: 20130200617
    Abstract: A power transmission system may include a plurality of renewable-energy devices such as wind turbines or subsea turbines. The devices are connected together in parallel to a subsea cable that carries an ac transmission voltage. Each device includes a turbine assembly that is rotated by wind or water current flows, and a variable speed ac induction generator. A power converter is connected to the subsea cable and is used to interface the generators to a supply network or power grid. The power transmission system is operated such that an indicated operating speed of one or more of the devices is used to control the power converter (e.g. the PWM strategy that is used to open and close the power semiconductor devices) to achieve desired stator electrical quantities at each generator.
    Type: Application
    Filed: April 4, 2011
    Publication date: August 8, 2013
    Applicant: GE Energy Power Conversion Tecnology Ltd
    Inventors: Christopher Alan Smith, Matthew James Moreman, Leonard William Burt, Matthew James Cunningham
  • Publication number: 20130049707
    Abstract: A DC chopper comprising a control unit and a power circuit and a DC chopping method for a DFIG (doubly fed induction generator) system are provided. The input terminal of the control unit is coupled to a DC capacitor of a converter to detect a DC voltage. The power circuit includes input terminals, an overvoltage protection module, a rectifier module and output terminals. The overvoltage protection module comprises at least one discharge unit formed from a discharge resistor and a switch element, and the rectifier module is coupled in parallel to the overvoltage protection module. When a grid voltage drops, the control unit outputs a corresponding control signal to drive the switch element to be ON or OFF, and the output terminal of the power circuit absorbs a portion of rotor inrush current, so as to impose over-current protection.
    Type: Application
    Filed: June 25, 2012
    Publication date: February 28, 2013
    Applicant: DELTA ELECTRONICS (SHANGHAI) CO., LTD.
    Inventors: Chang-Yong Wang, Jian-Fei Zheng, Fei Lu, Jian-Ping Ying
  • Publication number: 20120133343
    Abstract: A wind turbine connected to a power grid is provided. The wind turbine is selectively activated to operate at a high-voltage ride through (HVRT) mode. The wind turbine includes a grid voltage circuit, a DC bus, a voltage source, and a dynamic brake. The grid voltage circuit monitors a fundamental voltage of the power grid and activates the HVRT mode if the fundamental voltage is at least about equal to a threshold voltage value. The DC bus has a DC bus voltage. The voltage source provides a DC bus rated voltage. The dynamic brake has a brake chopper and a resistive element. The dynamic brake is connected to the DC bus. The dynamic brake is connected to the voltage source if the HVRT mode is activated.
    Type: Application
    Filed: December 12, 2011
    Publication date: May 31, 2012
    Applicant: GENERAL ELECTRIC COMPANY
    Inventor: Petar Jovan Grbovic
  • Publication number: 20120133342
    Abstract: A wind turbine generator includes a synchronous generator that generates electric power via rotation of a rotor provided with blades that receive wind and that supplies the generated electric power to a utility grid, and a sea water resistor in which sea water serves as a resistive element. When the output power of the synchronous generator drops suddenly because of a momentary power interruption caused by a fault occurring on the utility grid, thus producing surplus energy, the sea water resistor consumes, in the form of electric power, the surplus energy that cannot be supplied to the utility grid from among the electric power generated at the synchronous generator. Because the sea water resistor uses sea water as the resistive element, the problem of heat generation hardly ever arises, and because the sea water can be easily exchanged, it is not affected by lifetime or on-time limitations.
    Type: Application
    Filed: October 19, 2011
    Publication date: May 31, 2012
    Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventor: Naoto MURATA
  • Publication number: 20120049805
    Abstract: A power generation system that includes a prime mover configured to generate mechanical energy. The power generation system also includes a power generator configured for generating electrical power from the mechanical energy received from the prime mover. The power generation system further includes a fault ride-through switch electrically coupled in series between the power generator and a power grid. The fault ride-through switch includes a first branch configured to carry the electrical power during normal operating conditions and includes an LC resonance circuit. The fault ride-through switch also includes a multiphase transformer configured for providing voltage phases of different polarities to the LC resonance circuit.
    Type: Application
    Filed: August 26, 2010
    Publication date: March 1, 2012
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Ara Panosyan, Goran Drobnjak, Simon Herbert Schramm
  • Publication number: 20120007568
    Abstract: A rectifying unit rectifies an alternating current voltage induced across each of at least two-phase stator windings. A turn-on unit monitors an output voltage of the rectifying unit, and turns on a switching element as a low-side rectifying element for at least one of the at least two-phase stator windings when the output voltage exceeds a first threshold voltage due to load dump. After the output voltage, which exceeded the first threshold voltage once, falls below a second threshold voltage, a turnoff unit waits for turnoff of the switching element until a turnoff time suited for preventing occurrence of a surge across the at least one of the at least two-phase stator windings appears. The second threshold voltage is set to be lower than the first threshold voltage. The turnoff unit turns off, at the appearance of the turnoff time, the switching element.
    Type: Application
    Filed: July 8, 2011
    Publication date: January 12, 2012
    Applicant: DENSO CORPORATION
    Inventors: Harumi HORIHATA, Tadatoshi ASADA
  • Publication number: 20120001598
    Abstract: In a rotary electric machine, a load-dump protector turns on a switching element as a low-side rectifying element for at least one of plural-phase stator windings when the output voltage exceeds a first threshold voltage due to load dump. The load dump protector determines a turnoff timing of the switching element as the low-side rectifying element for the at least one of the plural-phase stator windings after the output voltage, which exceeded the first threshold voltage once, falls below a second threshold voltage. The second threshold voltage is set to be lower than the first threshold voltage. The load dump protector turns off, at the determined turnoff timing, the switching element as the low-side rectifying element for the at least one of the at least two-phase stator windings.
    Type: Application
    Filed: June 30, 2011
    Publication date: January 5, 2012
    Applicant: DENSO CORPORATION
    Inventors: Harumi HORIHATA, Yoshihide ITOH, Hideaki NAKAYAMA
  • Publication number: 20110316490
    Abstract: Switching control systems and methods are presented for controlling power conversion systems to provide electrical power to a grid or other load in which a synchronous machine is driven by a wind turbine or other prime mover to provide generator power to a switching type current source converter (CSC), with a current source rectifier (CSR) of the CSC being switched to provide d-axis control of the synchronous machine current based on grid power factor feedback, and with a current source inverter (CSI) of the CSC being switched to provide leading firing angle control and selective employment of dumping resists to dissipate excess generator energy in a fault mode when a grid voltage drops below a predetermined level.
    Type: Application
    Filed: September 9, 2011
    Publication date: December 29, 2011
    Applicant: ROCKWELL AUTOMATION TECHNOLOGIES, INC.
    Inventors: Yongqiang Lang, Navid Reza Zargari, Manish Pande, Bin Wu
  • Publication number: 20110248686
    Abstract: A method for the operation of a wind energy plant with a rotor, which transfers a driving moment to a generator via a drive train, wherein the generator provides a pre-settable generator moment acting opposite to the driving moment and is connectable to a grid, characterised in that after a sudden voltage change in the grid, the generator moment is controlled depending from the phase position of a torsional vibration of the drive train.
    Type: Application
    Filed: June 18, 2007
    Publication date: October 13, 2011
    Applicant: Nordex Energy GmbH
    Inventors: Matthias Thulke, Gunnar Schmidt, Thomas Frese, Eberhard Voss
  • Publication number: 20110215772
    Abstract: The invention discloses a power grid fault ride-through device and a method for a doubly fed induction generator.
    Type: Application
    Filed: July 23, 2010
    Publication date: September 8, 2011
    Applicant: SHENZHEN HOPEWIND ELECTRIC CO. LTD.
    Inventors: Xiaojun Sheng, Zhihua Wang, Quanbo Xia, Jianyou Zeng, Dangsheng Zhou, Ronghui Liao
  • Publication number: 20110101927
    Abstract: A power generation system includes a generator mechanically coupled to a turbine to generate electrical power. The system includes a fault ride through system having a variable resistor and a variable inductor. The variable resistor is connected in parallel across output terminals of the generator to absorb power from the generator during a grid fault condition, and the variable inductor is connected between an output terminal of the generator and a power grid.
    Type: Application
    Filed: November 4, 2009
    Publication date: May 5, 2011
    Applicant: GENERAL ELECTRIC COMPANY
    Inventors: Goran Drobnjak, Simon Herbert Schramm, Christof Martin Sihler
  • Patent number: 6924628
    Abstract: Method and system are provided for operating a generator using a dynamic capability curve. In one embodiment, the method allows providing a family of static capability curves corresponding to nominal reference levels of pressure of a fluid for cooling the generator. The method further allows acquiring data indicative of the actual pressure of the cooling fluid. A dynamic capability curve is generated to be responsive to the actual pressure of the cooling fluid. The family of static capability curves may be displayed relative to the dynamic capability curve, thereby allowing the operator to monitor and control the operation of the generator based on the actual pressure of the cooling fluid and further in view of at least one of the nominal reference levels of pressure for the cooling fluid.
    Type: Grant
    Filed: February 24, 2003
    Date of Patent: August 2, 2005
    Assignee: Siemens Westinghouse Power Corporation
    Inventor: Edward David Thompson
  • Patent number: 6919712
    Abstract: A reference voltage of an output terminal of a synchronous machine is set according to a reactive current output from the synchronous machine, a reference voltage of the high voltage side of a transformer, and a phase compensation transfer function to quicken attenuation of an electric power fluctuation.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: July 19, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hitomi Kitamura, Masaru Shimomura
  • Patent number: 6847184
    Abstract: An excitation controller controls excitation of a synchronous machine, which is connected to a power transmission system through a transformer, so that a high-side voltage of the transformer is maintained at a target voltage with high accuracy. An output terminal target voltage of the synchronous machine is set to precisely compensate for a voltage drop in the transformer, corresponding to the transformer phase angle variation. To achieve this result, the excitation controller detects an output terminal voltage and an output current of the synchronous machine and calculates active and reactive currents of the output current, sets the output terminal target voltage of the synchronous machine from the active and reactive currents, the high-side voltage of the transformer, and the reactance of the transformer, and controls excitation of the synchronous machine to compensate for the voltage drop in the transformer corresponding to phase angle variation of the transformer.
    Type: Grant
    Filed: May 21, 2003
    Date of Patent: January 25, 2005
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shinya Noguchi, Seiichi Tanaka, Masaru Shimomura
  • Publication number: 20040164717
    Abstract: Method and system are provided for operating a generator using a dynamic capability curve. In one embodiment, the method allows providing a family of static capability curves corresponding to nominal reference levels of pressure of a fluid for cooling the generator. The method further allows acquiring data indicative of the actual pressure of the cooling fluid. A dynamic capability curve is generated to be responsive to the actual pressure of the cooling fluid. The family of static capability curves may be displayed relative to the dynamic capability curve, thereby allowing the operator to monitor and control the operation of the generator based on the actual pressure of the cooling fluid and further in view of at least one of the nominal reference levels of pressure for the cooling fluid.
    Type: Application
    Filed: February 24, 2003
    Publication date: August 26, 2004
    Applicant: Siemens Westinghouse Power Corporation
    Inventor: Edward David Thompson
  • Patent number: 6757145
    Abstract: The power supply system includes an alternator that generates electric power according to the number of revolutions of an engine mounted in a vehicle and charges a predetermined battery; an output unit for outputting the electric power from the charged battery to the outside; a power generation control unit that detects the current amount of the electric power transmitted from the battery to the output unit and sets the number of engine revolutions according to the detected current amount; and an engine control unit that controls the number of revolutions of the engine in accordance with the number of engine revolutions set by the power generation control unit.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: June 29, 2004
    Assignees: Autonetworks Technologies, Ltd., Sumitomo Wiring Systems, Ltd., Sumitomo Electric Industries, Ltd.
    Inventor: Kouichi Takagi
  • Patent number: 5754030
    Abstract: Duty ratio of a power switching transistor connected to the field coil is controlled according to whether or not a high-power load is connected. When the high power load is not connected, the duty ratio is made 60%, for example, so that excessive power not generated. On the other hand, when the high power load is connected, the duty ratio is increased to 100% so that full power is generated by the generator. The power switching transistor is also controlled according to the battery voltage in a well known manner.
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: May 19, 1998
    Assignee: Nippondenso Co., Ltd.
    Inventors: Fuyuki Maehara, Tadatoshi Asada, Yasuhiro Takase, Wakako Kanazawa
  • Patent number: 5726557
    Abstract: A vehicular electric power system is composed of a rotating AC machine having polyphase armature coils, a full-wave rectifier for rectifying the generated voltages by a plurality of SiC-MOSFETs to give a rectified output to the battery unit, and a control device for selectively turning on the plurality of SiC-MOSFETs to raise the generated voltages by short-circuiting and open-circuiting the armature coils on the basis of the phases of voltages generated by the rotating AC machine at a predetermined duty factor.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: March 10, 1998
    Assignee: Nippondenso Co., Ltd.
    Inventors: Atsushi Umeda, Makoto Taniguchi, Shin Kusase
  • Patent number: 5512812
    Abstract: A vehicle generator control device comprises a detector adapted to detect whether or not a lamp load has been applied; and a control circuit. When an electric load is applied (i.e., when the terminal voltage of a battery is lowered) under the condition that the application of the lamp load has been detected, the control circuit suspends a load response control operation (increasing the field current of the generator by turning the field current switch on and off), and instead increases the field current abruptly by maintaining the field current switch conductive, thereby to increase the terminal voltage of the battery immediately. Thereby, a vehicle generator control device is provided which is free from a difficulty that, when a load response control operation is carried out with lamps with head turned on, the output light of these lamps are decreased or the lamps flicker.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: April 30, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Takahiko Ono
  • Patent number: 5374886
    Abstract: In a voltage regulator for an alternator which charges a battery via a charging cable and supplies a vehicle mains with voltage, the output voltage is regulated as a function of the temperature of the battery. The voltage regulator has a power part and a control part, which includes a simulation device for storing data and for determining the temperature of the battery, and hence the optimum charging voltage, by simulation from the stored data. Further, the voltage drop between the alternator and battery can be calculated from the alternator current and the resistance of the charging cable while taking into account correction factors which take into account the different connections of the consuming devices between the alternator and the battery so that the calculated voltage drop and the optimum charging voltage for the battery can be used by the voltage regulator to set the voltage delivered to the battery.
    Type: Grant
    Filed: July 10, 1992
    Date of Patent: December 20, 1994
    Assignee: Robert Bosch GmbH
    Inventors: Walter Kohl, Friedhelm Meyer, Rainer Mittag
  • Patent number: 5194800
    Abstract: The power supply system for a motor vehicle, includes a battery; a three-phase generator; a connecting line connecting the terminals of the generator and the battery; a rectifier connected electrically to the generator; a voltage regulator for switching an exciter field of the generator on and off to control a voltage actual value at the generator terminals and producing an average field current in the exciter field to maintain a power supply voltage substantially constant regardless of load and speed; and a circuit device for determining and for partially compensating an undesirable direct voltage drop at the generator terminals resulting from a voltage drop in the connecting line caused by load current. The device for determining and for partially compensating is structured to determine an alternating voltage at the generator terminals produced by an alternating current component in the connecting line.
    Type: Grant
    Filed: November 16, 1990
    Date of Patent: March 16, 1993
    Assignee: Robert Bosch GmbH
    Inventors: Gerhard Conzelmann, Karl Nagel, Andreas Junger
  • Patent number: 5182510
    Abstract: A system for charging a battery from a generator including a rectifier regulator wherein the regulated voltage is stepped up to compensate for voltage drops in the cable connecting the rectifier regulator to the battery.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: January 26, 1993
    Assignee: Sanshin Kogyo Kabushiki Kaisha
    Inventor: Kazuhiro Nakamura
  • Patent number: 5117174
    Abstract: An electric power system having line drop compensation includes a controllable electric power source having an output for supplying voltage to a power bus, a local voltage regulator for monitoring the output voltage of the power source and for producing a control signal representative of a desired nominal output voltage of the power source, and a remote voltage regulator for sensing voltage on the power bus at a point of regulation located away from the power source. The remote voltage regulator produces a pulse width modulated signal having a duty cycle representative of the voltage at the point of regulation. A pulse width to trim bias converter receives the pulse width modulated signal and produces the trim signal having a magnitude representative of the duty cycle of the pulse width modulated signal.
    Type: Grant
    Filed: October 3, 1989
    Date of Patent: May 26, 1992
    Assignee: Westinghouse Electric Corp.
    Inventor: Leland L. Kessler
  • Patent number: 5059886
    Abstract: A charging generator charges a battery by a voltage output from a generating unit having an armature coil and a field coil. The generator comprises a voltage boost/drop circuit connected between the output of the generator unit and the battery; a first control circuit connected between the field coil of the generating unit and the battery for controlling a field current flowing through the field coil to regulate a voltage generated in the armature coil of the generating unit in response to a voltage across the battery; and a second control circuit connected to the voltage boost/drop circuit for controlling the boost/drop ratio of the voltage boost/drop circuit.
    Type: Grant
    Filed: June 4, 1990
    Date of Patent: October 22, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shinji Nishimura, Kazutoshi Kaneyuki
  • Patent number: 4931717
    Abstract: A regulator is responsive to an input signal proportional to the system supply voltage for adjusting the current flowing in the field windings of an electrical alternator which controls the output power thereof. The primary regulation loop of the regulator generates a pulse train having a duty cycle inversely proportional to the amplitude of the input signal while an oscillator provides a sawtooth signal at a predetermined frequency which controls the response frequency of the regulator. The regulator limits the rate of increase in the duty cycle of pulse train upon detecting a decrease in the system supply voltage by converting the duty cycle of the pulse train to a charging signal for developing a voltage across a capacitor proportional to the duty cycle of the pulse train. The voltage across the capacitor is compared to the sawtooth signal and triggers a latch which disables the output signal of the regulator as the duty cycle lengthens in response to the decrease in the system supply voltage.
    Type: Grant
    Filed: September 5, 1989
    Date of Patent: June 5, 1990
    Assignee: Motorola Inc.
    Inventors: Randall C. Gray, Robert Jarrett
  • Patent number: 4785405
    Abstract: The power system stabilizer is provided at an individual power system to be separated due to an accident cutting off a link line which interconnects a number of power systems to form a large-scale power system. The power systems include power stations such as power plants and transformer substations. A simplified arithmetic processing unit of the stabilizer performs an arithmetic processing by a simple linear equation using an output frequency of a representative power station belonging to the separated power system immediately after the accident has been cleared, so that a total load drop of the separated power system can be assumed. Based on the assumption amount, balance control of demand and supply in the separated system is made.
    Type: Grant
    Filed: January 5, 1987
    Date of Patent: November 15, 1988
    Assignees: Chubu Electric Power Company, Inc., Mitsubishi Denki Kabushiki Kaisha
    Inventors: Taizo Hasegawa, Hirotaka Ono, Isao Koda, Tadahiro Gouda, Hideharu Oshida, Toshiharu Narita
  • Patent number: 4451777
    Abstract: There is provided a static VAR generator having voltage regulation in combination with the capability to damp subsynchronous resonance should it occur. A novel method for controlling subsynchronous resonance is provided by monitoring the frequency of the electrical generating system and controlling the insertion of compensating inductance in response to disturbances that may result in voltage and frequency pulsations.
    Type: Grant
    Filed: September 10, 1981
    Date of Patent: May 29, 1984
    Assignee: Westinghouse Electric Corp.
    Inventor: Laszlo Gyugyi
  • Patent number: 4442396
    Abstract: A generator system which is self-excited even during a fault condition includes a main generator having armature windings and a main field winding which is excited by a rotary transformer. The rotary transformer includes a stationary primary winding and a rotating secondary winding, with the primary winding receiving a controlled portion of the main generator armature output. The current through the primary winding of the transformer is controlled by silicon controlled rectifiers which are gated by a voltage regulator circuit. The voltage regulator circuit in turn receives signals from the voltage delivered to the load, the highest phase current delivered to the load and the voltage at the main generator armature output. The voltage regulator controls the current through the primary winding of the transformer in accordance with the voltage delivered to the load if that voltage is greater than a predetermined value.
    Type: Grant
    Filed: March 31, 1983
    Date of Patent: April 10, 1984
    Assignee: Sundstrand Corporation
    Inventor: David J. Hucker
  • Patent number: 4438386
    Abstract: There is provided a static VAR generator having a novel method for controlling subsynchronous resonance by monitoring the frequency of the electrical generating system and controlling subsynchronous resonance by phase-firing thyristor controlled inductance.
    Type: Grant
    Filed: September 10, 1981
    Date of Patent: March 20, 1984
    Assignee: Westinghouse Electric Corp.
    Inventor: Laszlo Gyugyi
  • Patent number: 4426613
    Abstract: A control circuit for a self-excited AC generator including an automatic voltage regulator, a fly-wheel capacitor which is charged normally by part of the generator output during a no-load operation or small-load operation of the generator, a detection circuit which detects a drop of the generator output voltage when said output voltage drops below the predetermined value, and a field current control circuit which operates on the fly-wheel capacitor to discharge the stored electric energy to the field winding of the generator or an exciter equipped with the generator when the detection circuit detects a drop of the generator output voltage. The control circuit provides additionally with the second field current control circuit which supplies a current from the generator output terminal to the field winding through a rectifier when the detection circuit detects a drop of the generator output voltage.
    Type: Grant
    Filed: March 23, 1983
    Date of Patent: January 17, 1984
    Assignee: Hokuetsu Industries Co., Ltd.
    Inventors: Masamitsu Mizuno, Kazuomi Itoh, Masahiro Urushibara