With Motor Driven Tap Switch Patents (Class 323/341)
  • Patent number: 9412527
    Abstract: An on-load tap changer for uninterrupted switching between different winding taps of a regulating winding of a tapped transformer in a transformer housing has at least one selector inside the housing for power-free selection of the respective winding tap of a tapped transformer that is to be switched over to and directly juxtaposed with the winding taps. It also has, spatially separate from the selector, a load-changeover switch for the actual switching from the connected to the new, preselected winding tap.
    Type: Grant
    Filed: July 7, 2011
    Date of Patent: August 9, 2016
    Assignee: MASCHINENFABRIK REINHAUSEN GMBH
    Inventors: Juergen Donhauser, Roland Meisel, Christian Pircher
  • Patent number: 9293288
    Abstract: In order to provide a high impedance between two sensor terminals, for instance for connecting a Rogowski transducer to a circuit breaker, but to prevent the coupling-in of interference signals in the case of a non-connection to the terminals, two auxiliary terminals are connected. In at least one embodiment, they are connected in such a manner that in the basic state, the sensor terminals are short circuited but in the case of a connection, for example of a plug to the sensor terminals and simultaneously to the auxiliary terminals, the short circuit is canceled with external short circuiting of the auxiliary terminals.
    Type: Grant
    Filed: August 28, 2012
    Date of Patent: March 22, 2016
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventor: Andreas Fischer
  • Patent number: 9184642
    Abstract: A system for harvesting energy including: an electrical machine including a first and a second structure, movable with respect to each other; a counterweight coupled to the second structure; a power transfer structure, electrically connected between the first structure and the load; an angular position sensor which provides a position signal ({right arrow over (?)}(t)) indicating the angular position of the counterweight; and an accelerometer which provides an acceleration signal ({right arrow over (a)}(t)) indicating an acceleration which affects the first structure.
    Type: Grant
    Filed: December 2, 2013
    Date of Patent: November 10, 2015
    Assignee: AKTIEBOLAGET SKF
    Inventors: Flavio Renga, Mario Rossi
  • Patent number: 9066578
    Abstract: A device connectable to an electric power line conductor including an electrically conductive insulated wire wound at least twice. A first end of the wire is configured to be connected to a first power line conductor and a second end of the wire is configured to be connected to a second power line conductor. A housing is mountable to the wire and includes an iron core power supply transformer configured to surround the wire to power a power supply module.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: June 30, 2015
    Inventor: Murray W. Davis
  • Publication number: 20140266142
    Abstract: The present disclosure provides techniques for an improved switching module for voltage regulators or transformers with voltage regulating taps. The switching module disclosed herein includes a first bypass switch and a second bypass switch coupled to the first bypass switch, at least one prime mover coupled to and configured to actuate at least one of the first bypass switch and the second bypass switch, and at least one load breaking switch coupled between the first and second bypass switches. In certain example embodiments, a separate prime move is configured to actuate each of the bypass switches and the load breaking switch. In certain other example embodiments, one or more of the bypass switches and the load breaking switch is actuated by a shared prime mover.
    Type: Application
    Filed: March 14, 2014
    Publication date: September 18, 2014
    Applicant: COOPER TECHNOLOGIES COMPANY
    Inventor: Jonathan Michael Schaar
  • Patent number: 8738301
    Abstract: The present invention relates to a method for quantitatively analyzing gases as a monitor for on-load tap changers. The general inventive concept lies in selecting particular characteristic gases allowing an indirect subsequent association and a dimension for aging effects, excessive discharge, and/or heating of the on-load tap changer; measuring said characteristic gases, formed during the operation of the tap changer in the insulating oil thereof, at particular time intervals; forming indicative quotients from the measured values of the defined gases, said quotients allowing direct conclusions about aging effects, excessive discharge, and/or heating; displaying trends from a comparison of the currently derived value of each quotient to the most recently derived value for the same quotient; and inferring warnings for aging effects, excessive discharge, and/or heating if the corresponding quotients tend to change significantly over time or in the course of the switch changes made.
    Type: Grant
    Filed: April 15, 2010
    Date of Patent: May 27, 2014
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Rainer Frotscher, Ralf Hartwig
  • Patent number: 8519681
    Abstract: A voltage regulator (10) for regulating a power distribution system voltage during forward or reverse power flow. The voltage regulator (10) accommodates multiple configurations of a tertiary winding (30) and a potential transformer (36) connected across source-side bushings (S/SL) or load-side bushings (L/SL). The invention simulates operation of a potential transformer (36), and the output voltage therefrom, connected across the source-side (S/SL) or load-side bushings (L/SL). The invention also produces a corrected voltage compensating a non-standard turns ratio of the tertiary winding (30). The regulator (10) controls a tap changer (18) to regulate the system voltage according to a digital value representing the voltage across the source-side (S/SL) or load-side bushings (L/SL), comprising a measured voltage, the corrected voltage or the simulated voltage.
    Type: Grant
    Filed: February 11, 2011
    Date of Patent: August 27, 2013
    Assignee: Siemens Energy, Inc.
    Inventor: Joel C. Mathewson
  • Patent number: 8135357
    Abstract: A switchable inductor-capacitor-inductor (L-C-L) network, which includes an integrated T/R switch, can advantageously bridge a PA and an LNA of a wireless device. The first inductor can function as an RF choke that provides power to the PA. In one embodiment, the first inductor can be advantageously implemented using the bond wires already attached to the PA, thereby requiring no additional inductors to provide the integrated T/R switch and minimizing use of valuable silicon area. The second inductor can function as a source inductor for and cancel an input parasitic capacitance of the LNA. A set of capacitors can act as blocking capacitors to provide DC isolation between the LNA and the PA, thereby protecting the LNA from high voltages. The L-C-L network can also advantageously function as an impedance matching network for at least one of the PA and the LNA.
    Type: Grant
    Filed: December 13, 2005
    Date of Patent: March 13, 2012
    Assignee: Qualcomm Atheros, Inc.
    Inventors: Richard T. Chang, David Weber
  • Patent number: 7893755
    Abstract: An internal voltage generation circuit includes a signal generation unit which generates first and second level signals and first and second control signals from a reference voltage generated by voltage-dividing an internal power and generates first and second driving signals by comparing levels of the internal power and the reference voltage, a driving control unit which receives the first and second level signals and drives the internal voltage in response to an active signal, and a driving unit which receives the first and second driving signals and drives the internal voltage.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: February 22, 2011
    Assignee: Hynix Semiconductor Inc.
    Inventor: Jae Hoon Kim
  • Publication number: 20100241286
    Abstract: A drive system for operation of a tap changer for voltage regulation of a transformer on load. An electric motor is connectible to a movable part of the tap changer for moving the movable part for carrying out a tap change operation. An electric converter connects an electric power supply to the electric motor. A control arrangement is adapted to control the electric converter for controlling the operation of the motor and by that of the tap changer.
    Type: Application
    Filed: August 24, 2007
    Publication date: September 23, 2010
    Applicant: ABB RESEARCH LTD.
    Inventor: Christer Thrornell-Pers
  • Patent number: 7432697
    Abstract: A control system providing a universal input for receiving a control signal for actuating tap-changing equipment. The system accommodates virtually any signal voltage level commonly used for control of the tap-changing equipment, modifies the received signal to a desired format, and inputs the modified signal to a controller for decoding and actuation of the tap-changing motor. The system is fully electronic, eliminating the use of electromechanical contacts for control of the tap-changer and providing a flexible approach to monitoring and diagnostics even from a location remote from the tap-changing equipment.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: October 7, 2008
    Assignee: ABB Technology Ltd.
    Inventors: Per Eriksson, Lahan Konov
  • Patent number: 7323852
    Abstract: A load tap changer (LTC) having a plurality of windings is coupled to one of the primary and secondary of a power transformer in order to regulate the output voltage of the transformer. The LTC includes a plurality of taps physically and electrically connected to and along the windings and a contacting element is selectively moved along the taps to increase or decrease the output voltage of the transformer. The power transformer and the LTC windings are placed in a main tank and the taps are placed in an LTC tank. The temperature in the main tank and the temperature in the LTC tank are monitored by means of first and second temperature probes whose outputs are used to sense the temperature differential (TDIFF) between the main tank and the LTC tank and to determine if the LTC tank temperature exceeds the main tank temperature for a period of time exceeding a specified time period. Also included is circuitry for sensing the rate of change of TDIFF and determining if it exceeds a predetermined value.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: January 29, 2008
    Inventor: Gary R. Hoffman
  • Patent number: 7319309
    Abstract: A system and method for remotely monitoring load tap changes on utility-type equipment are disclosed. In one example embodiment, a sensor measures a voltage before a tap change and compares the measured voltage to a voltage after the tap change. From this information, the direction of the tap change and the distance traveled can be determined. The system and method can also include a timer to measure an elapsed time required to complete a particular tap change and use this time information to determine the distance traveled. The direction of the tap change can be determined from a sensor that triggers the timer. The system and method thereby enable efficient and cost-effective remote monitoring of load tap changes and positions.
    Type: Grant
    Filed: November 18, 2004
    Date of Patent: January 15, 2008
    Assignee: Cannon Technologies/Cooper Power
    Inventors: Michael Cannon, Mark Peterson, Aaron Peterson
  • Patent number: 7023193
    Abstract: An ANSI Type A voltage regulator that eliminates the need for a potential transformer is disclosed. A control unit finds an output voltage by constantly monitoring the input voltage across the utility windings and the stored tap position. The value of the output voltage is further fine tuned by taking into account the effect of the impedance of the voltage regulator itself on the output voltage. The impedance is calculated using the instantaneous current through the regulator, the maximum rated current of the voltage regulator, the instantaneous voltage through the voltage regulator, the instantaneous Power Factor, and the tap position of the voltage regulator.
    Type: Grant
    Filed: June 21, 2004
    Date of Patent: April 4, 2006
    Assignee: Siemens Power Transmission & Distribution, Inc.
    Inventors: Robert Champion, Muhammad Sohail
  • Patent number: 6833518
    Abstract: A rotary tap changer is connected to a power source to control voltage supplied from the power source to a load. The rotary tap changer includes a motor having an output device, and a drive sprocket having a drive shaft positioned perpendicularly to a plane of rotation of the drive sprocket. The rotary tap changer also includes a gear engaged by the drive shaft, a first set of movable contacts, and a transmission device. The first set of movable contacts is coupled to the gear and mounted to conductively engage taps of an electrical control device. The transmission device is coupled to the motor output device and to the drive sprocket such that the motor directly drives the first set of movable contacts for selecting an electrical control device tap.
    Type: Grant
    Filed: November 6, 2003
    Date of Patent: December 21, 2004
    Assignee: McGraw-Edison Company
    Inventors: Christopher J. Byers, Augusto D. Hernandez, Dennis O. Conway, Neal Dirk
  • Patent number: 6693247
    Abstract: A rotary tap changer is connected to a power source to control voltage supplied from the power source to a load. The rotary tap changer includes a motor having an output device, and a drive sprocket having a drive shaft positioned perpendicularly to a plane of rotation of the drive sprocket. The rotary tap changer also includes a gear engaged by the drive shaft, a first set of movable contacts, and a transmission device. The first set of movable contacts is coupled to the gear and mounted to conductively engage taps of an electrical control device. The transmission device is coupled to the motor output device and to the drive sprocket such that the motor directly drives the first set of movable contacts for selecting an electrical control device tap.
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: February 17, 2004
    Assignee: McGraw-Edison Company
    Inventors: Christopher J. Byers, Augusto D. Hernandez, Dennis O. Conway, Neal Dirk
  • Patent number: 6664771
    Abstract: A power regulation system is coupled to an AC power source outputting an input voltage. The system has a first transformer to receive the input voltage and generate a control voltage. The system also has a second transformer that has a primary coil and a secondary coil. The primary coil and secondary coil of the second transformer are electromagnetically coupled to each other and so arranged that when the control voltage from the first transformer is applied to the primary coil, an output voltage is generated between a first end and a second end of the secondary coil, wherein the output voltage is substantially 180° out of phase from the input voltage so as to generate an effective voltage applied to the load, and wherein the effective voltage is less than the input voltage and substantially equals to the difference between the input voltage and the output voltage, resulting a reduction in power consumption of the load.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: December 16, 2003
    Assignee: PowerTec International
    Inventors: Robert L. Scoggins, Anythony D. Sheaffer, Michael A. Fulton, James O. Crompton, Jr.
  • Patent number: 6529858
    Abstract: A method of controlling a step switch. From the measured values of current, voltage and phase angle at an electric drive motor during actuation of the step switch the individual picked-up active output is calculated. From the active output the corresponding torque at the drive motor is calculated. The torque in the step switch which is crucial for controlling is determined on the basis of the torque by using a specifically calculated transfer function. The transfer function is newly determined every time the switch is actuated, with the values of the preceding switch operation or the preceding switch operations being taken as a basis of the new calculation.
    Type: Grant
    Filed: August 23, 2001
    Date of Patent: March 4, 2003
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Karsten Viereck, Mario Schmeckebier
  • Patent number: 6486641
    Abstract: A power regulation system is coupled to an AC power source outputting an input voltage. The system has a first transformer to receive the input voltage and generate a control voltage. The system also has a second transformer that has a primary coil and a secondary coil. The primary coil and secondary coil of the second transformer are electromagnetically coupled to each other and so arranged that when the control voltage from the first transformer is applied to the primary coil, an output voltage is generated between a first end and a second end of the secondary coil, wherein the output voltage is substantially 180° out of phase from the input voltage so as to generate an effective voltage applied to the load, and wherein the effective voltage is less than the input voltage and substantially equals to the difference between the input voltage and the output voltage, resulting a reduction in power consumption of the load.
    Type: Grant
    Filed: June 1, 2001
    Date of Patent: November 26, 2002
    Assignee: PowerTec International
    Inventors: Robert L. Scoggins, Anthony D. Sheaffer, Michael A. Fulton, James O. Crompton, Jr.
  • Patent number: 6396248
    Abstract: A power flow transformer implements power flow control in a transmission line of an n-phase power transmission system, where each phase of the power transmission system has a transmission voltage. The transformer has n secondary windings, where each secondary winding is on a core. The transformer also has n primary windings on the core of each secondary winding for a total of n2 primary windings, where one primary winding from each core is assigned to each phase. For each phase, the primary windings assigned to the phase are coupled in series, and the in-series primary windings receive the transmission voltage of the respective phase of the power transmission system. For each core, each primary winding thereon induces a voltage in the secondary thereon. The induced voltages are summed by the secondary to result in a summed induced voltage. Such summed induced voltage is a compensating voltage for a respective phase.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: May 28, 2002
    Assignee: ABB T&D Technology Ltd.
    Inventors: Kalyan K. Sen, Mey Ling Sen
  • Patent number: 6335613
    Abstract: A shunt compensating power flow transformer implements power flow control in a transmission line of an n-phase power transmission system, where each phase of the power transmission system has a transmission voltage. The transformer has n primary windings, where each primary winding is on a core and receives the transmission voltage of a respective one of the phases of the power transmission system. The transformer also has n secondary windings on the core of each primary winding for a total of n2 secondary windings, where each secondary winding has a voltage induced thereon by the corresponding primary winding. One secondary winding from each core is assigned to each phase. For each phase, the secondary windings assigned to the phase are coupled in series for summing the induced voltages formed thereon.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: January 1, 2002
    Assignee: ABB T&D Technology Ltd.
    Inventors: Kalyan K. Sen, Mey Ling Sen
  • Patent number: 6307283
    Abstract: A position indicator for step switches and tap selectors of transformers and the like has a contact array connected to the motor drive and connected by a plug to the plug of a connector which, in turn, is connected by plugs to the information-generating module which outputs to the display. One of the pairs of plugs between the contact array and the connector or between the connector and the module can be reversed relative to the other to signal a different sense of rotation of the motor drive.
    Type: Grant
    Filed: November 15, 1999
    Date of Patent: October 23, 2001
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Franz Griesbacher, Michael Holmer
  • Patent number: 6124726
    Abstract: A tap selector for a power transformer switchable under load is monitored by detecting the effective values of current and voltage of the drive motor of the tap changer. The power is calculated and from that the instantaneous torque and the latter is compared with setpoint values either of the torque and position of the tap selector or in terms of characteristic segments of the torque versus time graph with normalized segments of a setpoint graph so that, with serious deviation an immediate shutdown of tap selector operations is ensured or information can be generated as to trends or the need for maintenance.
    Type: Grant
    Filed: October 7, 1998
    Date of Patent: September 26, 2000
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Manfred Stadelmayer, Karsten Viereck
  • Patent number: 5952739
    Abstract: Multiple pairs of stationary and moveable contacts are toggled simultaneously between an open and closed position to disconnect or connect a meter from or to a line power source, by a reciprocating operator driven by low power clock motor. The operator is connected to the contacts through a series of pivotally coupled toggle links that are spring biased to maintain the contacts in either of two stable states, open or closed. The disconnect switch is housed as a modular unit that is interposed between the meter socket and the meter. The switch is remotely actuated and cycles the motor through a pre-determined number of degrees of rotation sufficient to change the state of the contacts.
    Type: Grant
    Filed: April 24, 1998
    Date of Patent: September 14, 1999
    Assignee: Eaton Corporation
    Inventors: William Ernest Grass, Earl Thomas Piber
  • Patent number: 5920467
    Abstract: A power converter for converting shore power voltage, phase, and frequency for shipboard use includes a variable inductance input transformer that can be connected to the shore power. The primary windings of the transformer have a plurality of taps, and a respective computer-controlled switch is connected between adjacent taps to selectively establish a closed circuit or an open circuit between the taps and thereby configure the primary windings as a low or high voltage "delta" or "wye", as appropriate for the shore power voltage. The output of the input transformer is sent to a variable speed drive, then to an output transformer, and thence to the distribution bus of the ship. A voltage regulator regulates the output voltage of the output transformer. If desired, a phase selector can be provided between the shore power and input transformer to establish the phase characteristics (i.e.
    Type: Grant
    Filed: August 1, 1997
    Date of Patent: July 6, 1999
    Assignee: Atlas Energy Systems, Inc.
    Inventors: Richard N. Bowyer, John S. Dale, Geoffrey West
  • Patent number: 5804953
    Abstract: A power converter for converting shore power voltage, phase, and frequency for shipboard use includes a variable inductance input transformer that can be connected to the shore power. The primary windings of the transformer have a plurality of taps, and a respective computer-controlled switch is connected between adjacent taps to selectively establish a closed circuit or an open circuit between the taps and thereby configure the primary windings as a low or high voltage "delta" or "wye", as appropriate for the shore power voltage. The output of the input transformer is sent to a variable speed drive, then to an output transformer, and thence to the distribution bus of the ship. A voltage regulator regulates the output voltage of the output transformer. If desired, a phase selector can be provided between the shore power and input transformer to establish the phase characteristics (i.e.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: September 8, 1998
    Assignee: Atlas Energy Systems, Inc.
    Inventors: Richard N. Bowyer, John S. Dale, Geoffrey West
  • Patent number: 5786552
    Abstract: The invention concerns a switching arrangement for load change-over switches of step switches and for selector switches, wherein two switching contacts movable in two directions are present. The first switching contact is in the form of a main switching contact and is connected to the load derivation by means of a first vacuum switchgear cell. The second switching contact is in the form of a resistance switching contact which is likewise connected to the load derivation by means of a series connection comprising a second vacuum switchgear cell and a transition resistor. Both the main and the resistance switching contacts can be moved independently of one another and without mutual coupling or influence. The main switching contact always reaches the new fixed contact abruptly and independently of the switching direction before the resistance switching contact leaves the previous fixed contact.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: July 28, 1998
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Hans-Henning Lessmann-Mieske, Josef Neumeyer, Leonhard Pillmeier
  • Patent number: 5773970
    Abstract: A tap changer in which a pair of selector contacts can be jointly movable or individually movable to engage stationary tap contacts of an array and one of the selector contacts is in series with a tickler coil and switchover resistor connected to one fixed contact of a bypass switch whose movable contact is connected to the load. The other selector contact is connected to one stationary contact of a switchover switch whose movable contact is connected to a second contact of the bypass switch while another contact of the switchover switch is tied to a point between the tickler coil and the resistor. A pair of oppositely poled parallel thyristors bridges the auxiliary network of the tickler coil and resistor and the main branch passing from the switchover switch to the bypass switch. The movable contacts are operated by an intermittent drive of the Geneva mechanism type.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: June 30, 1998
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Hans-Henning Lessmann-Mieske
  • Patent number: 5642290
    Abstract: A voltage regulator controller having integral expansion ports. The expansion ports are provided by way of an I/O expansion chassis which is electrically coupled to the controller's microprocessor.
    Type: Grant
    Filed: September 13, 1993
    Date of Patent: June 24, 1997
    Assignee: Siemens Energy & Automation, Inc.
    Inventors: Joseph F. Reilly, Michael A. Bellin, Carl J. Laplace, Jr., John J. Trainor
  • Patent number: 5528110
    Abstract: An improved voltage reduction apparatus specifically designed to overcome implementation problems of a prior art voltage reduction apparatus. The present invention is designed to overcome the problem of magnetic field flux induced harmonic distortion and heating associated with the prior art which otherwise substantially detracted from the advantageous implementation thereof. More specifically the present invention, also provides a highly advantageous apparatus for reducing voltage to a load, after first providing a full magnitude of voltage thereto by the use of an autotransformer having a series winding and a common winding disconnectable and connectable to one another by means of a relay or other equivalent switching device. However it also provides a bucking coil winding in parallel with the common winding and wound in bifilar opposed relation thereto.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: June 18, 1996
    Inventor: James M. Archdekin
  • Patent number: 5523674
    Abstract: The invention relates to a load selector for step switches in step transformers with two movable selector contacts. A suitable vacuum switch is located downstream of the first movable selector contact to switch the load current and a suitable switch for switching the compensation current is located downstream of the second movable selector contact. Both of the selector contacts are independently movable in such a way that one of the selector contacts moves slowly and the other selector contact rapidly moves or jumps between positions. The sequence of operation of the selector contacts is independent of the switching direction.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: June 4, 1996
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Josef Neumeyer, Wolfgang Albrecht, Gunter Kloth, Rolf Lauterwald, Hans-Henning Lessmann-Mieske
  • Patent number: 5516992
    Abstract: A cast-resin transformer has a transformer housing, a plurality of windings each having a plurality of taps, respective contacts connected to the taps and mounted on the housing in respective arrays which are all identical, and respective identical mounting elements on the housing at each of the contact arrays. Respective identical step switches each serve a respective winding of the transformer and each have a switch housing secured to the respective mounting element of the transformer housing at the respective contact array and a step contact movable along the respective connector elements and electrically engageable therewith. A drive motor and a main shaft are connected to all of the step contacts for synchronously stepping the step contacts along the respective connector elements.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: May 14, 1996
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Josef Neumeyer
  • Patent number: 5477113
    Abstract: An apparatus for applying a variable voltage to an electric load utilizes a transformer with several taps to provide different voltage levels for the load. The load is connected to alternate taps by a switching device, which is operated by a control device responsive to short interruptions in the power supply to the load. Short interruptions in power can be generated by rapidly turning one or more existing power switches in circuit with the load off and on again, so remote control is possible from several locations. Apparatus with the above structure is particularly suitable while employing a toroidal transformer for dimmer control of halogen lamps.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: December 19, 1995
    Assignee: Toroid Hong Kong Limited
    Inventor: Per M. Christoffersson
  • Patent number: 5107200
    Abstract: A switching system for a step transformer having at least two adjacent taps and a pair of terminals shiftable between the taps has a pair of fixed contacts normally connected to the terminals, a vacuum interrupter connected between the terminals and displaceable between an open-circuit position and a closed-circuit position, a pair of movable contacts each engageable with a respective one of the fixed contacts and forming therewith a respective bypass switch, and a cam rotatable about a cam axis and having a contact face and an axially oppositely facing interrupter face each formed with a respective operating formation. A drive rotates the cam about its axis through steps of a half revolution. A respective cam follower engaged between each of the movable contacts and the contact-face formation opens and closes one of the bypass switches on rotation of the cam through a half revolution and thereafter opens and closes the other of the bypass switches on rotation of the cam through a succeeding half revolution.
    Type: Grant
    Filed: March 27, 1991
    Date of Patent: April 21, 1992
    Assignee: Maschinenfabrik Reinhausen GmbH
    Inventors: Dieter Dohnal, Josef Neumeyer
  • Patent number: 5055766
    Abstract: An electronic device for compensating voltage fluctuations in an electrical power distribution circuit controls operation of a transformer of the type having a TCUL voltage regulator by automatically calculating the voltage bandwidth of the transformer based upon a stored value for peak current in the distribution circuit. The peak current value is automatically updated when the actual current in the circuit exceeds the stored peak current value for a predetermined sustained period of time indicating a change in overall loading patterns in the circuit but, regardless of increases in actual current in the distribution circuit, the apparatus prevents the output voltage from exceeding a preset absolute maximum.
    Type: Grant
    Filed: June 4, 1990
    Date of Patent: October 8, 1991
    Assignee: Duke Power Company
    Inventors: Brian McDermott, Robert L. Morgan
  • Patent number: 4591831
    Abstract: A position angle transducer for voltage compensating tap changing transformers provides secondary tap number or tap position analog output signals which accurately reflect the secondary tap position even if a non-linear relationship obtains between the shaft angle and tap number. A shaft angle sensor generates shaft angle analog signals and an analog-to-digital converter converts the shaft angle analog signals to shaft angle digital words. A digital-to-digital converter receives the shaft angle digital words and provides at its output tap number digital words according to the transfer function or functional relationship of tap changing shaft angle to tap number for the particular transformer. A programmable read-only memory performs the digital-to-digital conversion and is flexibly programmed according to the transfer function of the transformer and in order to establish any desired transfer functional relationship.
    Type: Grant
    Filed: May 8, 1984
    Date of Patent: May 27, 1986
    Assignee: Intelligent Controls, Inc.
    Inventor: Alexander D'Anci
  • Patent number: 4577146
    Abstract: An adjustable voltage transformer having a commutating surface formed of segments of electrical conductors upon which a contact brush is movable while in electrical engagement therewith. Means are provided to "step" the brush between segments, so that when at rest, the brush contacts no more than one segment, thus reducing short-circuiting currents and overheating; however, when the brush is being moved, it is in contact with two segments, thus allowing uninterrupted output from the transformer.
    Type: Grant
    Filed: June 12, 1984
    Date of Patent: March 18, 1986
    Assignee: The Superior Electric Company
    Inventor: Richard S. Lenzing
  • Patent number: 4540934
    Abstract: A multi-phase regulating transformer is disclosed having a plurality of windings cooperating with stepping trolleys which are driven by a common driving member. To obtain fine adjustment of the output voltage, the trolleys are coupled to the driving member with different plays to introduce a dead travel of the driving member relative to at least one trolley, which exceeds the spacing between two adjoining individual windings of the transformer.
    Type: Grant
    Filed: June 7, 1983
    Date of Patent: September 10, 1985
    Assignee: Schering Aktiengesellschaft
    Inventor: Egon Hubel
  • Patent number: 4388664
    Abstract: An apparatus for protecting a vacuum interrupter type on-line tap changer in which a cross current flows between taps through a current limiting resistor for a predetermined time by shorting selected taps therebetween at the time of tap changing operations. Vacuum interrupters are employed as current switching elements. A dial switch selects the position of the tap of the tap changer. A limit switch closes only at a predetermined position of the dial switch during tap changing operations. Thus, a cross current between the taps or a load current flowing for a long time due to a drop in the degree of vacuum of the vacuum interrupters is detected, thereby preventing burn-out of the current limiting resistor and damage to contacts of a disconnecting switch due to interruption of the current.
    Type: Grant
    Filed: August 3, 1981
    Date of Patent: June 14, 1983
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Tetsuo Watanabe
  • Patent number: 4386333
    Abstract: Different line-cord sets connect an electrical device to different supply voltages, assuring that the supply voltage matches the device. Each line-cord set has a uniquely keyed socket and a wall plug. A device receptacle receives the line-cord's keyed socket. An adjustable key on the device mates with the socket's key and rejects nonmating sockets to admit the socket into the receptacle and adjusts the device's input voltage to match the supply voltage.
    Type: Grant
    Filed: November 2, 1981
    Date of Patent: May 31, 1983
    Assignee: International Business Machines Corporation
    Inventor: George O. Dillan
  • Patent number: 4384247
    Abstract: An under-load switching device particularly adapted for use with a transformer having voltage taps for voltage regulation and for balancing the phase voltages in a multi-phase AC power system includes a pair of rotary tap selectors connected in parallel to the voltage taps, and a pair of switches for alternately connecting the tap selectors to an AC line, such that load current flows through only one tap selector and an associated switch at a time. A control unit monitors the voltage on the AC line, determines the tap required to be selected to compensate for voltage variations, causes the tap selector which is not carrying load current to select the required tap, and operates the switches at a zero-current point to transfer the AC line to the selected tap.
    Type: Grant
    Filed: May 8, 1981
    Date of Patent: May 17, 1983
    Assignee: TRW Inc.
    Inventor: Richard E. Stewart
  • Patent number: 4336490
    Abstract: An automatic voltage regulating transformer is provided which incorporates a potential transformer electrically disposed across its series windings, and a set of sensing windings disposed across its shunt windings to provide a voltage sensing network which is responsive to the flow of current both into and out of the transformer. The output of the potential transformer is connected in series with the sensing windings to provide a control voltage which is representative of the voltage across the shunt windings and series windings taken together. In the case of a normal voltage regulating transformer, this control voltage is proportional to the voltage across the output terminals. In the case of an inverted regulating transformer, the output voltage of the voltage sensing network is proportional to the voltage across the input terminals.
    Type: Grant
    Filed: January 28, 1981
    Date of Patent: June 22, 1982
    Assignee: McGraw-Edison Company
    Inventor: Charles E. Lewis
  • Patent number: 4309651
    Abstract: A wide range voltage regulator circuit exhibiting minimum circuit impedance at maximum output voltage employs a pair of regulating windings in series having their movable contact controlled by a plurality of normally open and normally closed limit switches. The extreme stationary contacts within the first regulating winding are connected with the movable contacts within the second regulating winding to provide a wide range of voltage regulation with negligible impedance at the maximum voltage position.
    Type: Grant
    Filed: August 11, 1980
    Date of Patent: January 5, 1982
    Assignee: General Electric Company
    Inventor: Robert H. Brennan