Stabilized, Anti-hunting Or Antioscillation Systems Patents (Class 307/102)
-
Patent number: 4887065Abstract: A control arrangement for a combined central locking and burglar alarm system for motor vehicles is constructed in such a manner that an accidentally tripped false alarm can be deactivated in a single manner by a designated key and a key detection switch associated with a door locking cylinder, so that the activation state of the burglar alarm system is automatically adapted to the existing locking state of the central locking system.Type: GrantFiled: October 31, 1988Date of Patent: December 12, 1989Assignee: Daimler-Benz AGInventors: Peter Robitschko, Klaus Claar, Hans Deischl, Josef Schumacher
-
Patent number: 4882563Abstract: A theft alarm is provided for a hood ornament utilizing a pair of spaced plugs held apart by a coil spring and retained together by a central hook and threaded post which extend through axial bores through the plugs with the hook extending up through the hole in the hood to engage the hood ornament. The plugs each mount an electrical contact, and when the ornament is deflected, the coil spring is compressed between the plugs, bringing the electrical contacts into contact and setting off an alarm, which ordinarily is the vehicle's horn.Type: GrantFiled: April 21, 1989Date of Patent: November 21, 1989Inventors: Marvin K. Perlman, Richard S. Perlman
-
Patent number: 4881148Abstract: A remote control system which includes (a) a receiver unit adapted to be fixedly mounted on a motor vehicle having at least one door lock with a first locked condition and a second unlocked condition and having means for receiving a coded signal including a code portion of binary bits, memory means for storing a first code of binary bits, means for comparing the code portion of a received coded signal with the first code and means for shifting the controlled device to one of the conditions upon the comparison match between the code portion of a received signal and the stored first code and (b) a transmitting unit for transmitting the stored second code of binary bits when the door lock is to be shifted into one of its conditions.Type: GrantFiled: October 19, 1988Date of Patent: November 14, 1989Assignee: Wickes Manufacturing CompanyInventors: George Lambropoulos, Kenneth R. Pitera, Robert A. Hair
-
Patent number: 4875350Abstract: A push lock actuable anti-theft vehicle device for a vehicle having a hood. A hood coupling member for coupling the hood to the vehicle is secured within an engine compartment of the vehicle and has a first locked position and a second unlocked position. The hood coupling member is operable by a keyed push lock member through a cable. An electrical contact is opened or closed by an engagement member of the push lock member upon actuation of the coupling member. The push lock member is manually operable to lock the coupling member and is operable by a restricted distribution key to unlock the coupling member.Type: GrantFiled: August 4, 1988Date of Patent: October 24, 1989Assignee: ABC Auto Alarms, Inc.Inventor: James H. Faust
-
Patent number: 4876649Abstract: A harm preventive mode for a vehicle is established upon detection of a condition that there is no occupant within the vehicle and the doors of the vehicle are closed, or an out-of-use condition of the vehicle, until the doors are unlocked by authentic unlocking means such as a door key. Measures which can be taken to prevent harm when the harm preventive mode is established include controlling the attitude of a driver's seat and/or steering wheel to reduce the spacing therebetween to resist against an attempted seating, energizing a horn or headlamp to bluff an aggressor or interrupting a fuel supply. In addition, various other conditions may be used in establishing the harm preventive mode. In this manner, a variety of effective measure to prevent harm to the vehicle can be taken.Type: GrantFiled: May 4, 1987Date of Patent: October 24, 1989Assignee: Aisin Seiki KabushikikaishaInventors: Taneichi Kawai, Tomio Yasuda, Koji Aoki
-
Patent number: 4868915Abstract: A keyless entry system has means for defining an interrogation zone. A marker responsive within the interrogation zone to generate a coded signal cooperates remotely with means for disengaging a locking mechanism upon verification of the coded signal when received.Type: GrantFiled: July 20, 1988Date of Patent: September 19, 1989Assignee: Allied CorporationInventors: Philip M. Anderson, III, James E. Kearney, Michael Suchomel, Jeffrey C. Urbanski
-
Patent number: 4866433Abstract: When an outside handle switch, a trunk cylinder switch, a glove box switch, or the like is caused to be in an on position, a combined transmitter/receiver circuit is caused to operate through an input discriminator. The input discriminator will initiate wireless communication between a user side main controller and a subcontroller through the intermediary of an antenna. The user side main controller is formed into a card and includes a loop antenna, a combined transmitter/receiver circuit, and a microcomputer. The user side subcontroller is formed into a card and includes a loop antenna, a combined transmitter/receiver circuit, and a microcomputer. When the combined circuit receives a signal from the main card lock and subcard lock, the signal is forwarded to the user side controller position discriminator circuit. This position discriminator discriminates the vehicle outside or vehicle inside position of the main card lock and the subcard.Type: GrantFiled: February 27, 1987Date of Patent: September 12, 1989Assignee: Kokusan Kinzoku Kogyo Kabushiki KaishaInventor: Shoji Akutsu
-
Patent number: 4866417Abstract: An improved vehicle intruder alarm system includes a method of automatically arming an alarm system. When arming the alarm system by remote control the vehicle windows can be raised and the vehicle headlights automatically turned on by remote control. When entering a vehicle door while the system is armed, a low warning tone is produced for an entry delay time. The warning tone increases with time. The processor for the alarm senses the magnitude and rate of impacts or motions of the vehicle. Short warnings are produced when the magnitude and rate are above a threshold.Type: GrantFiled: April 24, 1987Date of Patent: September 12, 1989Assignee: Specific Cruise Systems, Inc.Inventors: John M. DeFino, Neal G. Shields
-
Patent number: 4866296Abstract: An interrupt system for a circuit includes a single-pole, double-throw selector switch. The circuit may comprise an ignition circuit including a coil and a distributor normally innerconnected by a distributor wire. The selector switch has a first terminal, a second terminal connected to the coil and a third terminal connected to the distributor. The selector switch is movable between a first position connecting the first and second terminals and a second position connecting the second and third terminals. A delay switch is connected to the first and third terminals and has a normally closed position. The delay switch opens automatically in response to electrical current flowing therethrough.Type: GrantFiled: December 9, 1988Date of Patent: September 12, 1989Inventor: Stephen R. Thomas
-
Patent number: 4866416Abstract: An anti-theft device for a car radio having a theft module, which renders the car radio inoperative when the radio is slid out of its installation recess in the vehicle, is provided by a joint housing for a power supply and anti-theft protection plug connection elements, as well as for a change-over switch controlling the theft module. The housing is fastened via the plug connection elements at the rear wall of the car radio such that the change-over switch is inevitably actuated by the frame of the installation recess during the sliding-out of the radio.Type: GrantFiled: October 3, 1988Date of Patent: September 12, 1989Assignee: Daimler-Benz AktiengesellschaftInventors: Horst Holzhauer, Gunther Weikert, Rudi Kneib, Marko Polic, Peter Robitschko, Theodor Reinhard
-
Patent number: 4862139Abstract: A signal is received from a key having predetermined information. A resulting output signal is discriminated as to whether it represents the predetermined information. A predetermined anti-theft operation is actuated in response to output signals from first and second detectors indicating that at least one predetermined one of the covering members is closed and locked. Operation of the actuator is disabled in response to an output signal indicating that the received signal represents the predetermined information. The key includes a magnetic element forming first predetermined information, and light emitting elements for emitting infrared ray carrying second predetermined information. The predetermined anti-theft operation is actuated in response to an output signal from a third detector indicating that the key has been removed from a predetermined key hole, in addition to the output signals from the first and second detectors.Type: GrantFiled: August 16, 1988Date of Patent: August 29, 1989Assignees: Honda Lock Manufacturing Co., Ltd., Honda Giken Kogyo Kabushiki KaishaInventors: Masaaki Fukamachi, Nobuyuki Onitsuka, Akira Tanaka, Kazuo Nakamura
-
Patent number: 4860002Abstract: There is disclosed a power door lock system for use with an automobile, The lock system comprises an actuator for locking or unlocking a door or the tailgate, a microcomputer, a key code transmitter mounted on the vehicle, a key code receiver connected with the microcomputer, a nonvolatile memory in which a key code is stored, timers connected with the microcomputer, a passenger-detecting circuit, and a switch that is closed when the door is completely closed. The microcomputer includes a comparator for comparing the key code detected by the key code receiver with the key code stored in the memory. The operation of the actuator is controlled by the microcomputer to prevent malfunction.Type: GrantFiled: December 8, 1988Date of Patent: August 22, 1989Assignee: Aisin Seiki Kabushiki KaishaInventors: Tomoaki Imaizumi, Taneichi Kawai, Kouji Nishida, Yuuichi Murakami
-
Patent number: 4858060Abstract: A driving device for a door lock-actuator includes a door locking switch, a control circuit, a drive device and a counter. This device is free from the malfunctions and the restrictions of detecting limits which are problems in conventional-mechanical one-way switches, and can detect the locking and unlocking action certainly. In this device, the control circuit detects the locking and unlocking direction, and the drive device can drive the door lock-actuator of all the doors adjacent a passenger's seat according to the output signal from the control circuit.Type: GrantFiled: December 11, 1987Date of Patent: August 15, 1989Assignee: Jidosha Denki Kogyo Kabushiki KaishaInventors: Toshio Iwaoka, Masaru Inoue
-
Patent number: 4852680Abstract: An anti-theft security system for an off-road vehicle is disclosed. The system includes a master control module, which may be part of the vehicle's instrument cluster, and a remotely located security module, which is directly adjacent to at least one electrically-operated actuator of the vehicle normally operated as part of transporting the vehicle to another location. The security module includes a tamper-resistant housing which obstructs physical access to at least part of the actuator. The master module, which may include a microprocessor and LED display, has an operator interface such as a keypad for entering a first access code known only to authorized operators of the vehicle. When the sequence of entered keystrokes matches the first access code stored within the master module, the module automatically generates and transmits to the security module a signal containing a second and different access code.Type: GrantFiled: April 7, 1988Date of Patent: August 1, 1989Assignee: J. I. Case CompanyInventors: Thomas R. Brown, Richard H. Logan, Robert W. Hahn, Charles D. Rodeghiero, Kevin L. Brekkestran
-
Patent number: 4852681Abstract: An anti-theft device for motor vehicles which operates by cutting off the electrical supply to the ignition by a relay supplied by a central electronic unit which is connected in series with the "on" contact of the anti-theft steering lock of the vehicle characterized in that the relay is connected to the central unit through at least one transistor and to ground by a switch device which is maintained open while the engine is running.Type: GrantFiled: July 6, 1988Date of Patent: August 1, 1989Assignee: NeimanInventor: Jean Bombled
-
Patent number: 4848509Abstract: A central locking system for motor vehicles, not only doors and tailgate and gas tank-cap lids, but also several flaps of containers arranged in the passenger space (gloveboxes, small luggage compartments). These locks can be released and locked jointly by a unitary switch signal, or for specific conditions, both the doors and lids and the flaps can respectively be locked and released separately in groups.Type: GrantFiled: August 29, 1988Date of Patent: July 18, 1989Assignee: Daimler-Benz AktiengesellschaftInventors: Ulrich Bruhnke, Jurgen Korber, Helmut Fischer, Ingo Jobmann, Dieter Feichtiger, Hans Deischl, Gunther Weikert, Josef Schumacher, Klaus Claar
-
Patent number: 4845464Abstract: A user-programmable sensor system for generating an alarm signal upon detection of an alarm event is disclosed. The system is particularly suited for use in vehicle security systems. The system employs a three axes accelerometer as a shock/motion detector, and the transducer outputs are summed and the composite signal filtered to provide several channels, each covering a specific frequency or frequency band. The outputs of the channels are digitized and processed by a microprocessor. An event is characterized by seveal signal parameters with an alarm event triggered by the simultaneous occurrence of several predetermined conditions, and not just one condition. The limit values for the signal parameters which are required to qualify a shock/motion event as an alarm event may be readily programmed by the user at any time or place.Type: GrantFiled: August 9, 1988Date of Patent: July 4, 1989Assignee: Clifford Electronics, Inc.Inventors: Ze'Ev Drori, Moti Segal
-
Patent number: 4843513Abstract: A method by which a turbine generator (1, 2, 3) can be protected against sub-synchronous frequencies occurring in an electric network which is connected to the turbine generator and which incorporates capacitors. The method is based on de-equalizing the subsynchronous natural frequencies of the three phases, so as to weaken the coherence of the frequencies. This is achieved by incorporating in each of two of the phases a respective inductance L of mutually different size and by changing the capacitance equivalently with a series capacitance C such as to fulfill the condition 1/LC=.omega..sub.o.sup.2, where .omega..sub.o is the network frequency.Type: GrantFiled: March 28, 1988Date of Patent: June 27, 1989Assignee: Asea Brown Boveri ABInventor: Abdel-Aty O. M. Edris
-
Patent number: 4838570Abstract: Theft prevention of trailers and articulated vehicles and a method, control system and equipment to prevent the seizure of a vehicle combination and/or a trailer to be connected with a drawing or tractor vehicle.Type: GrantFiled: August 31, 1987Date of Patent: June 13, 1989Inventors: Ensio A. Toikka, Arto E. Toikka
-
Patent number: 4838377Abstract: An antitheft mechanism for an electronic device to be used in a car has three modes of operation. A normal operation mode permits continuous operation of the device. A line mode permits normal operation for a limited time after which it is replaced by a theft mode. The theft mode inhibits normal operation of the device until a secret code is entered into the device to return it to the normal mode or until a specified common operation of the device returns it to the line mode.Type: GrantFiled: February 26, 1988Date of Patent: June 13, 1989Assignee: Clarion, Co., Ltd.Inventors: Kengo Kozaki, Toshiyuki Nakazaki
-
Patent number: 4837453Abstract: A security device for locking the cable of a bonnet lock of a car comprising a housing with cable inlets. The inner core of the cable is secured to a cable engaging member which is movable within the housing on a pivot member about a pivot pin. A solenoid spindle mounted on the pivot member engages a bracket mounted on the housing to prevent pivotal movement of the cable engaging member. A compression spring biases the spindle into engagement with the bracket on de-energizing of the solenoid to lock the cable.Type: GrantFiled: November 28, 1986Date of Patent: June 6, 1989Assignee: Inventa Chemicals LimitedInventors: Michael J. Wiley, Stewart Irving, John P. McKeon
-
Patent number: 4835514Abstract: An antitheft system comprises a prohibition device for prohibiting the alarming operation upon receipt of a disarmed memory signal. When an arming signal is inputted, an alarm is generated on the receipt of a theft detection signal generated by handling or operation of vehicle equipment or accessories. When a disarming signal is received, on the other hand, it is sotred and held as the disarmed memory signal in power-supply disconnected state.Type: GrantFiled: April 27, 1987Date of Patent: May 30, 1989Assignees: Nippondenso Co., Ltd., Toyota Jidosha Kabushiki KaishaInventors: Mitsuhiko Masegi, Masao Sakurai, Makoto Aso
-
Patent number: 4835407Abstract: An automotive antitheft key arrangement for locking and unlocking an automotive vehicular door and for operating an ignition system includes a transmitter, first and second receiving means for receiving an input code signal sent from the transmitter unit, and a discriminator including a comparator which compares the input code signal received by the first or second receiving means with a present code signal. The discriminator produces a first or second comparator output when these signals match each other. In response to the first or second comparator output, electrical power is applied to a door lock mechanism for locking and unlocking the door or a starter motor for causing the engine starting operation. The door lock system further includes means for preventing either the first or second comparator output from being produced in response to turn ON or OFF of a starting switch so that the first comparator output is not produced when the second comparator output is produced, and vice versa.Type: GrantFiled: October 26, 1987Date of Patent: May 30, 1989Assignees: Nissan Motor Company, Ltd., Kokusan Kinzoku Kogyo Company, Ltd.Inventors: Sachiro Kataoka, Shunsaku Tsutsumi
-
Patent number: 4832146Abstract: An anti-theft device for an automotive vehicle is provided. It is positioned on top of a battery for an automobile or the like which is provided with positive and negative terminals. The anti-theft device is located within a housing having upper and lower sections. The lower section has an opening for receiving the positive pole and a battery clamp.The anti-theft device receives a positive pole of the battery. The battery clamp fits over the positive pole. The anti-theft device includes a key actuated switch connected by a main power source to a new positive pole. This main power source is switch controlled.A constant power supply is connected to a resistor and by electrical connections to the key actuated switch through the positive pole of the battery. By timely use of the key actuated switch, the anti-theft device can be turned on and off to secure the automotive vehicle.Type: GrantFiled: November 6, 1987Date of Patent: May 23, 1989Inventor: Jeffrey C. Luby
-
Patent number: 4831356Abstract: An automobile theft prevention device has an idle swing mechanism including first, second, and third levers. The first and second levers are coaxially coupled to each other for angular movement and connected between an engine hook lock and an engine hood lever for opening the engine hood. The third lever is actuatable by means of a solenoid for in turn moving a connecting pin loosely fitted within slots defined respectively within the first and second levers. When an automobile door is locked, the solenoid is energized so as to move the connecting pin disposed within the slots into a position where the first lever is idly movable with respect to the second lever. Thus, the engine hood cannot be opened even if the engine hood lever is operated. The connecting pin can be moved back to its original position so as to connect the first and second levers only when the door is unlocked properly as by, for example, by means of a key for the door.Type: GrantFiled: August 1, 1988Date of Patent: May 16, 1989Assignee: Shiroki Kinzoku Kogyo Kabushiki KaishaInventor: Hideo Ito
-
Patent number: 4821025Abstract: A vehicle cover alarm apparatus is provided for use on a vehicle equipped with an "electronic security system". The alarm apparatus comprises a bracket which carries an electrical switch. An electrical conductor electrically connects the switch to the electronic security system on the vehicle. A cable is connected to the switch and extends from the switch outwardly of the vehicle. The cable is adapted for connection to a vehicle cover and when so connected, creates a tension on the cable which causes the switch to move to a first switch position. A biasing means such as a spring biases the cable against the action created by the tension on the cable. Thus, when the vehicle cover is released from the cable, the spring will automatically bias the switch to its initial switch position.Type: GrantFiled: August 24, 1987Date of Patent: April 11, 1989Inventor: Lawrence D. Ross, Sr.
-
Patent number: 4819050Abstract: Electronic disabling circuits are provided to prevent the engine of a motor vehicle to be protected from starting in the event of an attempt at starting the vehicle while the disabling circuits are switched on by a switch. An inhibitor device serves to prevent the disabling circuits from stopping the engine in the event the switch is actuated in an untimely manner while the engine is running. In addition, a detector for detecting the presence of a human being serves, via a circuit, to reliably trigger an alarm in the event of an intrusion, by applying a detection signal to an input of the circuit, assuming the circuits have been switched on by the switch.Type: GrantFiled: January 20, 1988Date of Patent: April 4, 1989Assignee: Societe Manzoni-BouchotInventor: Bernard Manzoni
-
Patent number: 4816803Abstract: An alarm circuit for detecting the opening of any door of a semi trailer. The alarm circuit has power supply 11, negatively grounded with the positive terminal electrically connected to a keyed rotary switch 16. A double pole double throw relay 14 is electrically connected at terminal five to the output terminal of the keyed rotary switch is electrically connected at its terminal five to the output terminal of the keyed rotary swtich 16. A green indicator lamp 19, which is grounded is electrically connected to a normally open single pole single throw momentary push button switch 17 and to terminals three and seven of the relay 14. The other end of the normally open single pole single throw momentary push button switch 17 is electrically connected to the output terminal of the keyed rotary switch 16. An alarm horn 13, which is grounded, is electrically connected to terminal number one of relay 14.Type: GrantFiled: February 26, 1988Date of Patent: March 28, 1989Inventor: Kennith W. Brown
-
Patent number: 4812670Abstract: A theft protection electric cable includes at least one conducting core, a sheath which is least partially insulating, and a suitable connection. The cable is characterized in that it is connected between a source of electrical voltage and a user member by at least one contactor (3), said contactor receiving information concerning the conducting or non-conducting state of the cable and including a spring or switch (11, 34) for interrupting the passage of electricity as a function of said information.Type: GrantFiled: August 6, 1987Date of Patent: March 14, 1989Inventor: Michel Goulet
-
Patent number: 4811013Abstract: An external controller embodied in a portable card communicates by wireless signal with a controller mounted internally of a vehicle to control locking and unlocking operations of the vehicle doors in response to coincidence between codes respectively stored in the internal vehicle controller and the external controller, and manually entered through door switches mounted externally of the vehicle. Such door opening operation may be performed even with the portable card unintentionally left in the vehicle.Type: GrantFiled: April 10, 1986Date of Patent: March 7, 1989Assignee: Kokusan Kinzoku Kogyo Kabushiki KaishaInventor: Shouji Akutsu
-
Patent number: 4785405Abstract: 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: GrantFiled: January 5, 1987Date of Patent: November 15, 1988Assignees: Chubu Electric Power Company, Inc., Mitsubishi Denki Kabushiki KaishaInventors: Taizo Hasegawa, Hirotaka Ono, Isao Koda, Tadahiro Gouda, Hideharu Oshida, Toshiharu Narita
-
Patent number: 4724333Abstract: Damping of supersynchronous oscillations in an ac power system is accomplished by a damping circuit connected between a power line and a system neutral potential. The damping means includes a tuned circuit having a resonant frequency above the system operating frequency. Preferably, the tuned circuit further has an antiresonant frequency at the system frequency. The supersynchronous damping circuit in accordance with the invention can be used with subsynchronous damping circuits known in the prior art to enhance the damping of oscillations in the ac power system.Type: GrantFiled: April 10, 1985Date of Patent: February 9, 1988Assignee: Electric Power Research InstituteInventor: Ronald A. Hedin
-
Patent number: 4701689Abstract: The present invention relates to an automatic device for depressing low frequency oscillation of power system. It consists of an electronic circuit incorporated in the original excitation regulator of a synchronous generator. This circuit can turn the input deviation of voltage .DELTA.V into simulating state variable deviations of angular frequency .DELTA..omega., of power .DELTA.P and of power angle .DELTA..delta., and then outputs the sum of them according to the principle of optimal control. With the device of the present invention, the output capability of a remote power station may double, a whole set of measurement and feedback devices may be spared and the distortions in measurement may be avoided. The present device has further advantages of being small in size, cheap in cost, easy to establish and high in reliability.Type: GrantFiled: April 4, 1986Date of Patent: October 20, 1987Assignee: Huazhong Institute of TechnologyInventors: Ren Yuan, Chen Xianzhi, Feng Yuanxi, Li Guojiu, Huang Dake, Zhang Yongli, Sun Quanzhong
-
Patent number: 4567423Abstract: Subsynchronous oscillations in a polyphase power network can be effectively damped with a switching arrangement having a thyristor-switched regulation and a phase shifting polyphase power system. The arrangement is controllable and is periodic in nature, being responsive to a measurement signal representing a physical parameter of the subsynchronous oscillations. This signal preferably represents the difference between the instantaneous rotational frequency of the generator and a set-point value for that frequency. Control windings are connected in series with the power-network-side polyphase windings of a block transformer. Voltages induced in these control windings are phase shifted with respect to the voltages in the respective associated power-network-side polyphase windings of the block transformer. These voltages in the control windings produce a very effective damping torque on the generator, to damp out the subsynchronous oscillations.Type: GrantFiled: April 9, 1984Date of Patent: January 28, 1986Assignee: BBC Brown, Boveri & Company, LimitedInventors: Josip Dobsa, Adel Hammad
-
Patent number: 4434376Abstract: Subsynchronous oscillations and DC offset in an electrical power system are dampened by measuring the half-cycle period of current or voltage line waves, comparing the measured half-cycle time periods to a desired half-cycle time period and dissipating the line waves in measured half-cycle time periods which are longer than the desired half-cycle time period. Damping apparatus includes a reactance connected in a power line with selectively bidirectional conductors in parallel with the reactance whereby the reactance can be shorted. Alternatively, the selectively bi-directional conductors can connect a power line to ground or neutral when half-cycle time periods exceed a desired half-cycle time period.Type: GrantFiled: April 13, 1981Date of Patent: February 28, 1984Assignee: Electric Power Research Institute, Inc.Inventor: Narain G. Hingorani
-
Patent number: 4355241Abstract: Reactance means serially connected in a power line is shunted by selectively bidirectional conduction means which is triggered in response to half-cycle time periods of current waves exceeding a desired half-cycle time period and also in response to an over voltage across the reactance means.Type: GrantFiled: August 15, 1980Date of Patent: October 19, 1982Assignee: Electric Power Research Institute, Inc.Inventor: Narain G. Hingorani
-
Patent number: 4292580Abstract: A circuit arrangement, for deriving, from sensed power variations in a network, a signal for supplying the exciter of at least one synchronous machine coupled to the network, includes first and second vector identifiers, each providing a direct and phase-shifted output with each of the outputs coupled through an impedance matching amplifier to a summing junction. The direct signal from the first vector identifier and phase-shifted signal from the second vector identifier are conducted to one summing junction and the phase-shifted output of the first vector identifier and direct output of the second vector identifier to a second summing junction, with the outputs of the two summing junctions summed at a further summing junction after being coupled through additional impedance matching amplifiers to result in a total signal at the output of the third summing junction which varies in a mathematically positive sense with increasing oscillation frequency.Type: GrantFiled: November 30, 1979Date of Patent: September 29, 1981Assignee: Siemens AktiengesellschaftInventors: Gunther Ott, Wolfgang Kaufhold
-
Patent number: 4292545Abstract: Subsynchronous oscillations and DC offset in an electrical power system are dampened by measuring the half-cycle period of current or voltage line waves, comparing the measured half-cycle time periods to a desired half-cycle time period and dissipating the line waves in measured half-cycle time periods which are longer than the desired half-cycle time period. Damping apparatus includes a reactance connected in a power line with selectively bi-directional conductors in parallel with the reactance whereby the reactance can be shorted. Alternatively, the selectively bi-directional conductors can connect a power line to ground or neutral when half-cycle time periods exceed a desired half-cycle time period.Type: GrantFiled: July 23, 1979Date of Patent: September 29, 1981Assignee: Electric Power Research Institute, Inc.Inventor: Narain G. Hingorani
-
Patent number: 4017790Abstract: An alternating current power transmission system employing a long transmission line has a stabilizing arrangement comprising a plurality of alternating current saturated reactors connected to intermediate stations along its length, at least some of the reactors having slope correction capacitors in series therewith, and others of the reactors having slope reactances which are not connected by series slope correction capacitors. Since the uncompensated reactors have a substantially instantaneous transient response the stabilizing arrangement gives an overall voltage control which is better than one incorporating only slope corrected reactors.Type: GrantFiled: October 14, 1975Date of Patent: April 12, 1977Assignee: Associated Electrical Industries LimitedInventor: Erich Siegfried Friedlander
-
Patent number: 3953741Abstract: A stepwise control for two-step control operations comprising a series of switching stages which for each stage value of a control magnitude as the input magnitude switches-on a corresponding stage value of a physical output magnitude as an adjustment magnitude and each of which possess switching hysteresis, the width of which is defined by the difference of the values of the input magnitude for switching-in and switching-off the switching stage, there being present a smallest stage value of the output magnitude and the value of the output magnitude of a subsequent stage is greater by the amount of such smallest stage value than that of the preceding stages and the total value of the output magnitude is divided over the switching stages into such partial values that by switching-on and/or switching-off the switching stages it is possible to portray the individual stage values of the output magnitude.Type: GrantFiled: December 19, 1974Date of Patent: April 27, 1976Assignee: Stata-Control System SCS AGInventor: Urs Winkelmann