Transformer (e.g., Split Core Admits Conductor Carrying Unknown Current) Patents (Class 324/127)
  • Patent number: 7746056
    Abstract: An electronic circuit includes a substrate having a surface and a device supported by the surface of the substrate. The electronic circuit also includes a magnetic field transducer disposed over the surface of the substrate and an insulating layer disposed between the substrate and the magnetic field transducer. The electronic circuit also includes a conductor disposed over the magnetic field transducer. The conductor is configured to carry an electrical current to generate a first magnetic field. The electronic circuit is responsive to the first magnetic field.
    Type: Grant
    Filed: January 22, 2009
    Date of Patent: June 29, 2010
    Assignee: Allegro Microsystems, Inc.
    Inventors: Jason Stauth, Richard Dickinson, Glenn Forrest, Ravi Vig
  • Publication number: 20100156393
    Abstract: A current sensor includes a coil for sensing current in a current carrying bus, and a mount for mounting the coil to the current carrying bus at a distance from the bus. A system including the current sensor includes similar structure.
    Type: Application
    Filed: December 18, 2008
    Publication date: June 24, 2010
    Applicant: GENERAL ELECTRIC COMPANY
    Inventor: Brian Eric Lindholm
  • Patent number: 7733094
    Abstract: An apparatus for monitoring and measuring the electrical, thermal and mechanical operating parameters of high voltage power conductors. A toroidal shaped housing, which can be mounted onto an energized conductor, contains all of the necessary electrical instruments to monitor the parameters associated with the conductor. Moreover, the housing includes the processing capability to analyze disturbance and fault events based on these parameters.
    Type: Grant
    Filed: October 31, 2005
    Date of Patent: June 8, 2010
    Assignee: Underground Systems, Inc.
    Inventors: James Bright, Larry Fish, John Engelhardt, Paul Alex, Duncan Breese
  • Patent number: 7733080
    Abstract: The clamp meter contains a revolving member configured between the meter's body member and jaw member. The revolving member is composed of a first base and a second base located on the interfacing sides of the body member and the jaw member, respectively. The first base and the second base are revolvably joined together by an axle extended axially from the body member into the jaw member via the first and second bases' aligned axle holes. The first base has at least a roller ball elastically embedded in a concave and exposed towards the second base. The roller ball would roll into one of a number of notches of the second base as the base and jaw members are rotated relative to each other, thereby creating a number of preset configurations of the included angle between the body and jaw members.
    Type: Grant
    Filed: November 20, 2008
    Date of Patent: June 8, 2010
    Assignee: Chung Instrument Electronics Industrial Co., Ltd.
    Inventor: Shaw-Lin Liu
  • Patent number: 7728578
    Abstract: In order to extend the measurement range of a current sensor, a current divider is formed by a first conductor formed in a current sensor that is mounted on a printed circuit board and a second conductor on the printed circuit board that electrically shorts at least one input terminal of the current sensor to at least one output terminal of the current sensor. The input terminal of the current sensor supplies the current to be measured to the first conductor and the output terminal supplies the measured current back to the printed circuit board.
    Type: Grant
    Filed: May 15, 2008
    Date of Patent: June 1, 2010
    Assignee: Silicon Laboratories Inc.
    Inventors: Brett E. Etter, Donald E. Alfano, Timothy J. Dupuis, Donald K. Coffey
  • Publication number: 20100123454
    Abstract: The clamp meter contains a revolving member configured between the meter's body member and jaw member. The revolving member is composed of a first base and a second base located on the interfacing sides of the body member and the jaw member, respectively. The first base and the second base are revolvably joined together by an axle extended axially from the body member into the jaw member via the first and second bases' aligned axle holes. The first base has at least a roller ball elastically embedded in a concave and exposed towards the second base. The roller ball would roll into one of a number of notches of the second base as the base and jaw members are rotated relative to each other, thereby creating a number of preset configurations of the included angle between the body and jaw members.
    Type: Application
    Filed: November 20, 2008
    Publication date: May 20, 2010
    Inventor: SHAW-LIN LIU
  • Patent number: 7710104
    Abstract: A load measuring circuit including a cable including first and second conductors and a shielding. The conductors are connected by a first end thereof to a load, the shielding is not connected to a ground at the end, and the conductors are connected to a generator by the second end thereof. A transformer includes a first winding connected to a conductor on the second end of the cable, a second winding is connected between a ground and the shielding on the second end of the cable, and a third winding is connected to a current measuring member.
    Type: Grant
    Filed: October 19, 2006
    Date of Patent: May 4, 2010
    Assignee: Renault s.a.s.
    Inventors: Andre Agneray, Clement Nouvel
  • Patent number: 7701197
    Abstract: An electrical current sensing assembly comprises: a conductive input substrate with a generally planar contact surface; a conductive output substrate with a generally planar contact surface proximate and substantially parallel to the input substrate contact surface; a conductive current sense path extending from the input substrate contact surface to the output substrate contact surface with a sense path cross sectional area generally normal to electrical current flow; a conductive current bypass path extending from the input substrate contact surface to the output substrate contact surface with a bypass path cross sectional area generally normal to electrical current flow; and an electrical current sensing device proximate the current sense path for sensing electrical current passing through the current sense path; wherein the ratio of the current passing through the bypass path to the current passing through the sense path is proportional to the ratio of the bypass path cross sectional area to the sensing p
    Type: Grant
    Filed: April 20, 2008
    Date of Patent: April 20, 2010
    Assignee: Hamilton Sundstrand Corporation
    Inventors: Randal Sherman, Shin Katsumata
  • Patent number: 7696743
    Abstract: In a zero-phase current detecting apparatus, a feedback loop is made up of a pulse generating unit, a current detecting unit, a peak detecting unit, an adding unit, and a current regulating unit. The adding unit outputs a difference between a target value and a peak value detected by the peak detecting unit. A zero-phase current is detected based on the difference output from the adding unit as a result of regulation of the peak value so as to be the target value in the adding unit.
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: April 13, 2010
    Assignee: Mitsubishi Electric Corporation
    Inventors: Daisuke Tajima, Hirokazu Nakabayashi, Naoki Nishio
  • Publication number: 20100085782
    Abstract: A resonant converter comprises switching circuitry (1) for supplying pulses, at a controllable frequency, to a resonant circuit so as to power the primary circuit (3, 12) of a transformer (4). The secondary winding (5a, 5b) of the transformer (4) delivers an AC signal which is rectified and then produces a load current. On the primary side, the converter has a resistor (13) for deriving a first electrical signal representative of the current in the primary circuit (3, 12), and an auxiliary winding (14) which is closely coupled to the secondary winding (5a, 5b) and across which an auxiliary voltage is induced as a consequence of the close coupling of the winding (14) to the secondary winding (5a, 5b). A resistor/capacitor combination (16, 17) integrates the auxiliary voltage with respect to time to derive a second electrical signal.
    Type: Application
    Filed: February 25, 2008
    Publication date: April 8, 2010
    Applicant: NXP, B.V.
    Inventor: Hans Halberstadt
  • Publication number: 20100085036
    Abstract: A power line monitoring device is mounted to a power line. The device includes circuitry for monitoring the power line and communicating information regarding the power line. A ground reference point of the circuitry is electrically coupled to the power line. Therefore, the monitoring device, including its circuitry, has substantially the same voltage potential as the power line. Accordingly, there is a substantially equalized or uniform electric field around the device. The substantially equal voltage potential and electric field allow communications with the monitoring device to have reduced noise and interference, as compared to other devices that have different voltage potentials than their corresponding power lines. A pad of semi-conductive material may be disposed between the power line and the electrical conductors to slow a rate of change of the voltage potential of the device circuitry when mounting the device to the power line, thereby minimizing risk of corona discharge.
    Type: Application
    Filed: September 29, 2009
    Publication date: April 8, 2010
    Applicant: Cooper Technologies Company
    Inventors: John Fredrick Banting, Gregg James Haensgen, Bruce W. McBee
  • Publication number: 20100060261
    Abstract: The coupling device with electrical isolation comprises at least one input signal, an output of an output signal representative of said input signal, and signal transfer means with electrical isolation receiving the input signal and supplying said output signal. The transfer means comprise at least one signal transformer having at least one primary winding to receive a primary signal representative of said input signal, switching means to switch the input signal and supply the latter to said primary winding, and electrically isolated control means of the switching means comprising a control input receiving control signals during switching periods. The electrical switchgear unit comprises one such coupling device connected to measuring resistors and to a processing unit processing electrical protection functions.
    Type: Application
    Filed: December 10, 2007
    Publication date: March 11, 2010
    Applicant: Schneider Electric Industries SAS
    Inventors: Yvan Cadoux, Didier Leonard, Bruno Reymond
  • Patent number: 7671580
    Abstract: An integrated current sensing transformer includes a bobbin, a magnetic core assembly, a first primary winding element, a second primary winding element, a secondary winding element. The bobbin has a receptacle therein. The magnetic core assembly is partially embedded into the receptacle for providing a closed path of magnetic flux. The first primary winding element is wound around the bobbin for inputting a first test current therein. The second primary winding element is wound around the bobbin for inputting a second test current therein. The secondary winding element is wound around the bobbin for outputting a sensing current when either the first test current or the second test current is sensed. The magnitude of the sensing current is directly proportional to the magnitude of the first test current or the second test current.
    Type: Grant
    Filed: November 30, 2006
    Date of Patent: March 2, 2010
    Assignee: Delta Electronics, Inc.
    Inventor: Wen-Kuan Hsu
  • Publication number: 20100045263
    Abstract: The current measurement device with electrical isolation comprises an input signal connected to an electrical shunt, an output of an output signal, and signal transfer means with electrical isolation receiving the input signal and supplying said output signal. The transfer means comprise at least one signal transformer having at least one primary winding to receive a primary signal representative of said input signal, switching means to switch the input signal and supply the latter to said primary winding, and electrically isolated control means of the switching means comprising a control input receiving control signals during switching periods. A trip unit and an electrical circuit breaker comprises one such current measurement device and a processing unit processing electrical protection functions.
    Type: Application
    Filed: December 10, 2007
    Publication date: February 25, 2010
    Applicant: SCHNEIDER ELECTRIC INDUSTRIES SAS
    Inventors: Yvan Cadoux, Didier Leonard, Bruno Reymond
  • Patent number: 7667452
    Abstract: Detector circuit for measuring relatively strong currents including a main current transformer (1) and two substantially identical auxiliary current transformers (2, 3) where a main current (I1) induces magnetomotive forces in said main current transformer (1), said magnetomotive forces being counteracted by magnetomotive forces induced by a compensating current (i1) while at the same time the two auxiliary transformers (2, 3) are magnetised in antiphase by means of a square wave/modulation signal. Furthermore the detector circuit includes a synchronous rectifier for generating an adjusting signal for the compensating current (i1). According to the invention a compensating current is used for measuring current in a common winding (L3) surrounding the main transformer as well as the auxiliary transformers while at the same time a possible error signal in the shape of a voltage difference between the auxiliary transformers is used to adjust the compensating current (i1) by means of a negative feedback loop.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: February 23, 2010
    Assignee: Liaisons Electroniques-Mecaniques LEM S.A.
    Inventor: Andreas Marcussen
  • Patent number: 7663459
    Abstract: A short-circuit indicator is provided for arrangement on an electrical line for electrical power distribution which includes a current transformer. The current transformer has an induction coil and an iron yoke for surrounding the electrical line to be monitored for a short-circuit current. The induction coil is seated on a base web of a U-shaped first yoke part. A second yoke part is connected in the form of a joint which can move between a closed position and an open position to one of two U-limbs of the first yoke part. The second yoke part forms a magnetic return path element for the first yoke part in the closed position. The first yoke part is split into two essentially L-shaped parts in the area of the base web to which the induction coil is fitted.
    Type: Grant
    Filed: June 23, 2008
    Date of Patent: February 16, 2010
    Assignee: Dipl.-Ing. H. Horstmann GmbH
    Inventor: Hendrik Horstmann
  • Publication number: 20100033165
    Abstract: A device for measuring currents induced in a CAN bus harness. In some embodiments, the device includes a first termination node, a second termination node, a current separator, a detection circuit, and a power source circuit. The current separator circuit has an RF transformer connected to the first termination node and separates a common mode RF current and a differential mode RF current of an RF current signal. The detection circuit is connected to the current separator circuit and receives at least one of the common mode RF current and the differential mode RF current from the separator circuit. The detection circuit also converts the common mode RF current and differential mode RF current to an non-RF output signal. The power source circuit provides power to the detection circuit.
    Type: Application
    Filed: August 6, 2008
    Publication date: February 11, 2010
    Applicant: Robert Bosch GmbH
    Inventors: Cyrous Rostamzadeh, Sergio A. Pignari
  • Patent number: 7659709
    Abstract: An electric current sensor having a housing, magnetic circuit with a magnetic core, and a magnetic field detector with a detection cell, positioned in an air gap between ends of the core. The core is made of a non-laminated magnetic material, and the magnetic circuit has a strap made of non-magnetic material welded to the core at each side of the air gap. The magnetic field detector has a support plate on which the detection cell is mounted. The plate has a recess, opposition the detection cell, which houses one end of the magnetic circuit.
    Type: Grant
    Filed: November 14, 2007
    Date of Patent: February 9, 2010
    Assignee: Liaisons Electroniques-Mécaniques LEM S.A.
    Inventors: Gerard Lepine, Olivier De Loriol, Gilles Moret, Thierry Chenavard
  • Patent number: 7659710
    Abstract: A current clamp meter having a current meter body and a detachable current clamp. The current meter body and the current clamp are configured so that the current clamp is detachable from the current meter body and the meter is operable with the current clamp either attached to the current meter body or detached from the current meter body.
    Type: Grant
    Filed: October 20, 2008
    Date of Patent: February 9, 2010
    Assignee: Fluke Corporation
    Inventors: Shounan Luo, Wang Yong
  • Patent number: 7656266
    Abstract: A toroidal power transformer is disclosed. The toroidal power transformer comprises a circular core composed of plurality of laminated electrically conductive materials, a plurality of multi-layered first windings radially wound around the circular core, said winding arranged with an angular spacing of 2? and a number of windings in each winding layer is less than a number of windings in each previous layer, a multi-layered second winding radially wound around the circular core covering a corresponding one of said plurality of first windings, wherein the layers of each of said second windings are arranged to form a substantially triangular cross-section; and an insulating layer between each of said first and second windings.
    Type: Grant
    Filed: January 9, 2008
    Date of Patent: February 2, 2010
    Inventor: Kern K. N. Chang
  • Patent number: 7656149
    Abstract: A current transformer detects a sine-wave alternating current having a maximum effective current value Imax(Arms) and a frequency f(Hz) and a half-sine-wave rectified current having a maximum peak value Ipeak(Aop) and a frequency f(Hz) in a primary winding, consisting of at least one magnetic core with one turn of primary winding and at least one multiple turns of secondary winding to which a detecting resistor is connected.
    Type: Grant
    Filed: August 13, 2008
    Date of Patent: February 2, 2010
    Assignee: Metglas, Inc.
    Inventor: Shin Nakajima
  • Publication number: 20100020457
    Abstract: Relay devices, systems and methods for obtaining an accurate representation of a current monitored with a Rogowski coil, without integration of the Rogowski coil output voltage signal in the time domain.
    Type: Application
    Filed: September 24, 2009
    Publication date: January 28, 2010
    Applicant: COOPER TECHNOLOGIES COMPANY
    Inventors: Ljubomir A. Kojovic, Stephen E. Williams
  • Publication number: 20100013460
    Abstract: A Rogowski sensor is provided for measuring a current of an electrical conductor. The sensor has a Rogowski coil, which has an electrical winding resistor, and an integration device which is connected to the Rogowski coil and is intended to generate an output signal which is proportional to the electrical current to be measured by the Rogowski sensor. The integration device is formed by the winding resistor of the Rogowski coil and a capacitance which is connected to the two winding connections of the Rogowski coil, and for the output signal from the integration device to be formed by the voltage applied to the capacitance.
    Type: Application
    Filed: December 12, 2007
    Publication date: January 21, 2010
    Applicant: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Jochen Ermisch, Uwe Hering, Frank Thieme, Ralf-Reiner Volkmar
  • Publication number: 20100007336
    Abstract: There is disclosed a method of monitoring an electrical network of the type having a feeder line connected to a plurality of distribution transformers, each distribution transformer being in turn coupled to a load which may be provided with a customer meter. The method includes the steps of recording an accumulated in-phase current at each of the distribution transformers over a time period and recording for the same time period an accumulated in-phase current at the feeder line. The sum of the accumulated in-phase currents recorded at the distribution transformers are then compared to the accumulated in-phase current recorded at the feeder line. The method may also include the steps of recording accumulated in-phase currents at the customer meters and comparing their sum with the accumulated in-phase current measured at the distribution transformers coupled to the customer meters.
    Type: Application
    Filed: January 12, 2009
    Publication date: January 14, 2010
    Inventor: Eric George de Buda
  • Patent number: 7642768
    Abstract: A current sensor includes a magnetic field sensing element, a first conductor including sandwich structure and second conductor including sandwich structure electrically coupled to one another. The magnetic field sensing element is interposed between the first and second sandwich structure. The magnetic field sensing element is operable to receive magnetic flux lines resulting from current flowing through the first and second conductor sandwich structure. The first and second conductor sandwich structure each include a top portion including at least a first electrical conductor, a bottom portion including at least a second electrical conductor, and a layer of magnetic permeable material different from the first and second electrical conductor interposed between the top portion and bottom portion.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: January 5, 2010
    Assignee: Honeywell International Inc.
    Inventor: Helmut Kinzel
  • Patent number: 7638999
    Abstract: Relay devices, systems and methods for obtaining an accurate representation of a current monitored with a Rogowski coil, without integration of the Rogowski coil output voltage signal in the time domain.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: December 29, 2009
    Assignee: Cooper Technologies Company
    Inventors: Ljubomir A. Kojovic, Stephen E. Williams
  • Patent number: 7633287
    Abstract: A core is divided by alternately arranging plural magnetic material portions and plural non-magnetic material portions in a circumferential direction of the core through which a primary conductor penetrates. A conductor is wound around the core under conditions in which each core cross section of the core intersects the magnetic material portion and the non-magnetic material portion, each core cross section including a cut end surface of each conductor of a secondary winding wound around the core, and a ratio of a magnetic material portion cross-sectional area of the magnetic material portion to a non-magnetic material portion cross-sectional area of the non-magnetic material portion at the core cross section is kept constant at each core cross section.
    Type: Grant
    Filed: October 22, 2008
    Date of Patent: December 15, 2009
    Assignee: Mitsubishi Electric Corporation
    Inventors: Ryuichi Nishiura, Yo Makita, Hiroshi Nishizawa, Tadahiro Yoshida, Tae Hyun Kim
  • Publication number: 20090289618
    Abstract: In a zero-phase current detecting apparatus, a feedback loop is made up of a pulse generating unit, a current detecting unit, a peak detecting unit, an adding unit, and a current regulating unit. The adding unit outputs a difference between a target value and a peak value detected by the peak detecting unit. A zero-phase current is detected based on the difference output from the adding unit as a result of regulation of the peak value so as to be the target value in the adding unit.
    Type: Application
    Filed: August 31, 2006
    Publication date: November 26, 2009
    Applicant: Mitsubishi Electric Corporation
    Inventors: Daisuke Tajima, Hirokazu Nakabayashi, Naoki Nishio
  • Patent number: 7622910
    Abstract: Integrated current sensors are used in AC electric power systems. An integrated current sensor according to one embodiment comprises: an inductor (101), wherein an AC current passes through the inductor (101); an integrator circuit (103), the integrator circuit (103) receiving a voltage associated with the AC current; a gain control circuit (116) operationally connected to the integrator circuit (103), the gain control circuit (116) outputting a gain controlled signal; and a compensation circuit (115) operationally connected to at least two of the integrator circuit (103), the gain control circuit (116), and the inductor (101), to compensate for parameter variation induced in the gain controlled signal or in the output of the integrator circuit (103).
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: November 24, 2009
    Assignee: Honeywell International Inc.
    Inventor: Hassan Ali Kojori
  • Patent number: 7615988
    Abstract: A current measurement technique is disclosed in which a family of transformer coils having the same number of turns and the same winding resistance may be associated an active circuit for presenting a burden resistance of substantially zero value. The impedance of the coils will vary with their window size, and the active circuitry will reduce the burden resistance accordingly so that reductions and impedance do not result in introducing additional error into measurements. The circuitry may be used for measuring current in single conductors or in multiple conductors passing through the transformer coil, such as for ground fault measurement, monitoring and control.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: November 10, 2009
    Assignee: Rockwell Automation Technologies, Inc.
    Inventor: John Herman Blakely
  • Patent number: 7615989
    Abstract: Integrated current sensors are used in DC electric power systems. An integrated current sensor (200B) according to one embodiment comprises: a DC inductor (111B) including a resistive component and an inductive component, wherein a DC current passes through the DC inductor (111B); an integrator circuit (161), the integrator circuit (161) receiving a voltage associated with the DC inductor (111B); and a feedback system operationally connected to the DC inductor (111B) and to the integrator circuit (161), to subtract a voltage associated with the resistive component and obtain a voltage associated with the inductive component.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: November 10, 2009
    Assignee: Honeywell International Inc.
    Inventor: Hassan Ali Kojori
  • Patent number: 7598724
    Abstract: A current transformer assembly includes at least one Rogowski coil having a first closeable loop with an electrically conductive coil member and a first pair of terminals. An integrator unit has respectively a cable connected across the first pair of terminals of a respective Rogowski coil. Each respective Rogowski coil provides an output voltage received by the integrator assembly caused by when a respective electrical conductor on a phase of a multiphase circuit is arranged within an opening of the closeable first loop of the respective Rogowski coil, and provides an output signal proportional to a current in a conductor arranged in an opening of a Rogowski coil. At least one of the Rogowski coils includes an inline calibration unit for fast calibration and recalibration when retrofitting a monitor module that monitors a value of the current in one or more conductors.
    Type: Grant
    Filed: January 17, 2008
    Date of Patent: October 6, 2009
    Assignee: Admmicro Properties, LLC
    Inventors: Donald W. Howell, Samuel A. Taylor, Danny K. Dyess, Frank O. Blevins, Mark W. Vinson
  • Publication number: 20090219009
    Abstract: A current measurement device is disclosed that is configured to measure electrical current, both AC and DC, in a primary conductor that is electrically insulated from the current measuring device. Unlike known current measuring devices, the current measuring device in accordance with the present invention does not utilize a Hall effect device and is more accurate and less expensive than current measuring devices employing such Hall effect devices. The current measuring device in accordance with the present invention includes a transformer with a saturable magnetic core formed with a central aperture and a current measuring circuit. In one embodiment of the invention, the transformer is provided with a secondary winding and no primary winding. The electrical conductor, i.e. primary conductor, in which electrical current is to be measured is disposed in the central aperture of the magnetic core and thus acts as a primary winding having a single turn.
    Type: Application
    Filed: February 28, 2008
    Publication date: September 3, 2009
    Inventors: Arian M. Jansen, Huian Dong
  • Patent number: 7583075
    Abstract: The present invention is a subtractive current measuring system for a power receptacle. The system may comprise one or more of the following features: (a) a power receptacle; (b) a current carrying input wire; (c) a current carrying output wire; (d) a current transformer; (e) an electrical measuring device; and (f) interconnecting circuitry linking the current transformer and the electrical measuring device.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: September 1, 2009
    Assignees: Geist Manufacturing, Inc., Aphel, Ltd.
    Inventor: Hugh G. Hutchison
  • Patent number: 7570045
    Abstract: The present invention is an attachment device and a method for fastening and removing an electrical cable monitoring instrument to an electrical cable. The attachment device comprises monitoring instrument sensor with opening for positioning electrical cable such that said electrical cable can be positioned to pass through the sensitive volume at least partially surrounded by said sensor, at least one elongated elastic member securely attached to said cable monitoring instrument such that, when elastically deformed to a shape characterized by high mechanical energy such that deformed elastic member allows said electrical cable access to and from the sensitive volume at least partially surrounded by said monitoring instruments sensor.
    Type: Grant
    Filed: October 12, 2006
    Date of Patent: August 4, 2009
    Assignee: James G. Biddle Company
    Inventors: Gregory Robert Wolfe, William Eakins Ferguson, Jr., Andrew Paul Sagl, Jeffrey Lyn Stitt
  • Patent number: 7557563
    Abstract: A sensor apparatus for measuring power parameters on a power conductor, such as a high voltage transmission line may include a corona structure, an electronics assembly and a conductor mountable device. The corona structure may define an outer boundary surrounding the electronics assembly and the conductor mountable device. The corona structure may shield the electronic assembly and conductor mountable device from a corona produceable with the power conductor. The conductor mountable device may be a power parameter measurement device, such as a current sensor assembly. The current sensor assembly may be a split-core design that includes multiple transformer cores. The electronics assembly and the conductor mountable device may powered from a line voltage suppliable on the power conductor. Data may be wirelessly transmitted and received with the sensor apparatus.
    Type: Grant
    Filed: January 19, 2006
    Date of Patent: July 7, 2009
    Assignee: Power Measurement Ltd.
    Inventors: Colin N. Gunn, Stewart J. Harding, Marc A. Ricci, Daniel N. Loewen, Peter C. Cowan, Martin A. Hancock
  • Patent number: 7545138
    Abstract: A current measurement device using a Rogowski coil having a generally toroidally shaped core with flattened faces, a first winding in one direction, a second winding forming a return loop, and a temperature compensation and scaling network coupled to the coil. The core has concentric cavities and a rough surface to restrain movement of the coil winding. A Faraday shield is wrapped over the coil. One shield is “serpentine,” having staggered (offset) lateral extensions from a central region. An alternate shield has a generally circular central region with extensions in generally radial directions. The shield is formed of three layers comprising a non-ferromagnetic metal central layer surrounded by insulative layers. At an end tab of the shield, the metal layer is exposed for connection to a ground lug or other connector. An insulative housing envelops the coil and electrical network. An output wire terminates in an industrial connector. A resistive network may be implemented with the current measurement device.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: June 9, 2009
    Assignee: Schweitzer Engineering Laboratories, Inc.
    Inventors: Donovan E. Wilkerson, Veselin Skendzic, James R Kesler
  • Patent number: 7541800
    Abstract: Methods and systems for an electrical meter are provided. The meter includes a current sensor configured to be communicatively coupled to a conductor, and a processor communicatively coupled to the current sensor wherein the processor is configured to receive signals indicative of current flow through the conductor and wherein the processor is further configured to process the signals to determine an imbalance between the positive half cycle of the current flowing through the conductor and the negative half cycle of the current flowing through the conductor to detect a DC influence on the current sensor.
    Type: Grant
    Filed: July 16, 2007
    Date of Patent: June 2, 2009
    Assignee: General Electric Company
    Inventors: Robert Edward Lee, Jr., Donald Frank Bullock
  • Patent number: 7538541
    Abstract: A split Rogowski coil assembly having distinct coil loops formed on printed circuit boards that are not joined to one another.
    Type: Grant
    Filed: November 6, 2006
    Date of Patent: May 26, 2009
    Assignee: Cooper Technologies Company
    Inventor: Ljubomir A. Kojovic
  • Patent number: 7532001
    Abstract: Provided is a Q-boosting circuit for improving a Q factor in a radio frequency (RF) integrated circuit of a semiconductor device using a transformer instead of an inductor. The Q-boosting circuit couples a negative resistance circuit to a pair of terminals of a transformer to reduce a resistance component of the transformer, thereby increasing a mutual inductance component. Therefore, it is possible to obtain a more improved Q factor than a conventional Q factor through adjustment of an inductance and a resistance component, and to obtain the Q factor having a wide range from several tens to several hundreds according to a frequency range.
    Type: Grant
    Filed: June 6, 2006
    Date of Patent: May 12, 2009
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Young Jae Lee, Hyun Kyu Yu
  • Publication number: 20090115400
    Abstract: The sensitivity and accuracy of a status indicator for sensing a current in an electrical circuit is improved by shifting the reference level of the transformer output to maximize the input signal to a precision voltage detector and by reducing the hysteresis of the status indicator by balancing the burden of the current transformer during the positive and negative alternations of the AC signal and by driving secondary loads with a voltage to current converter.
    Type: Application
    Filed: August 13, 2008
    Publication date: May 7, 2009
    Inventor: Phillip Hunter
  • Publication number: 20090115403
    Abstract: The size of a status indicator for monitoring a current in a power cable is reduced by integrating a bobbin for the secondary winding with a current transformer core and integrating a circuit board including output terminals with a current transformer assembly.
    Type: Application
    Filed: August 13, 2008
    Publication date: May 7, 2009
    Inventor: James Bernklau
  • Patent number: 7528594
    Abstract: The present invention is related to a device (1) for the detection of direct and/or alternating current to be used in the realization of highly sensitive amperometric measuring instruments or for the detection of differential faults along with automatic switches. The inventive device comprises a magnetic core (5) disposed in such a manner to surround at least one current-carrying conductor (6). A winding (10) surrounds the magnetic core (5) and is electrically connected to an electrical resistance (60). A voltage source (40) generates a drive voltage (Vexcit) which permits the circulation of a pick-up current (Iexcit) in the said winding (10) and in the said core (5). Amplification means (20) are used to detect the voltage (Vsense) at the terminals of the resistance (60) in order to generate a first signal (Vamp1) which is representative of the above defined current (Iexcit).
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: May 5, 2009
    Assignee: ABB S.p.A.
    Inventors: Romano Manzoli, Francesco Viaro
  • Patent number: 7525297
    Abstract: An impedance-compensated current transformer comprising a primary winding, a power source electrically coupled through the primary winding; a secondary winding magnetically coupled to the first primary winding, the secondary winding having a secondary winding impedance and a secondary winding resistance; and an impedance-compensation circuit electrically coupled across the secondary winding; wherein the impedance-compensation circuit actively reflects to the secondary winding a virtual impedance which is equal in magnitude and opposite in polarity to the secondary winding impedance.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: April 28, 2009
    Assignee: FALCO Ltd.
    Inventor: Umberto Gibellini
  • Patent number: 7518354
    Abstract: An electronic circuit includes a first substrate having a first substrate surface and a device supported by the first substrate surface. The device is selected from among a passive electronic component and an active electronic component. The electronic circuit also includes a second substrate having a second substrate surface and a conductor proximate to the second substrate. The electronic circuit also includes a magnetic field transducer disposed over the conductor and coupled to the device and an insulating layer disposed between the conductor and the second substrate. The conductor is adapted to carry an electrical current to generate a first magnetic field. The electronic circuit is responsive to the first magnetic field. In some embodiments, the conductor is a secondary conductor and the circuit further includes a primary conductor disposed proximate to the magnetic field transducer and an insulating layer disposed between the primary conductor and the second substrate.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: April 14, 2009
    Assignee: Allegro Microsystems, Inc.
    Inventors: Jason Stauth, Richard Dickinson, Glenn Forrest, Ravi Vig
  • Patent number: 7518529
    Abstract: A monitoring device (1) for monitoring the electrical properties of a medium voltage overhead line (3) in a medium voltage network comprises three separate measurement sensors (2a, 2b, 2c), each being adapted for direct connection onto a medium voltage overhead line. Each of the measurement sensors has means to draw operating power from the medium voltage overhead line. The measurement sensors measured results may be combined for accurate measurement analysis.
    Type: Grant
    Filed: January 31, 2003
    Date of Patent: April 14, 2009
    Assignee: FMC Tech Limited
    Inventors: Charles Brendan O'Sullivan, Michael Martin Quinlan
  • Publication number: 20090072813
    Abstract: An intelligent electronic device (IED), e.g., an electrical power meter, having circuitry for reducing the burden placed on at least one current sensor of the device resulting in a highly accurate measurement by the at least one current sensor is provided. The circuitry of the present disclosure reduces the burden on the current sensor while providing amplification, e.g., gain control, to the input signal. The circuitry includes at least one current sensor outputting a signal to an operational amplifier (op amp) having a controlled variable feedback resistance. By employing an operational amplifier in the circuitry, the output of the current sensor will be at a near zero volts condition at all times thus reducing the burden on the current sensor.
    Type: Application
    Filed: September 16, 2008
    Publication date: March 19, 2009
    Applicant: Electro Industries/Gauge Tech.
    Inventor: Tibor Banhegyesi
  • Publication number: 20090066317
    Abstract: The present invention is a meter for recording voltage and current on a transformer. The device has a housing with a body portion and a lever portion, the lever portion being movable between a closed position wherein the lever portion abuts the body portion and an open position wherein the lever portion is positioned away from the body portion. The device includes a pair of current sensors each current sensor being divided into two corresponding sensor fractions with one fraction of each sensor formed on the body portion of the housing and the other corresponding fraction formed on the lever portion of the housing. The fractions of each sensors are constructed such that each of the current sensors have a central opening dimensioned to receive one of the transformer terminals when the lever portion of the housing is in its first position. The current sensors are positioned on the housing such that the meter can be mounted to the terminals of the transformer.
    Type: Application
    Filed: July 11, 2008
    Publication date: March 12, 2009
    Inventor: Eric de Buda
  • Publication number: 20090058399
    Abstract: A method of manufacturing a clamp jaw assembly for a clamp meter is provided. The method includes providing a clamp jaw core and a shield having a channel. The method further includes positioning the clamp jaw core within the channel of the shield such that the shield surrounds a portion of the clamp jaw core. The method also includes enclosing the clamp jaw core and the shield within a clamp jaw housing.
    Type: Application
    Filed: August 30, 2007
    Publication date: March 5, 2009
    Applicant: FLUKE CORPORATION
    Inventors: Yong Wang, Yinhong Yang
  • Publication number: 20090039870
    Abstract: A current clamp meter having a current meter body and a detachable current clamp. The current meter body and the current clamp are configured so that the current clamp is detachable from the current meter body and the meter is operable with the current clamp either attached to the current meter body or detached from the current meter body.
    Type: Application
    Filed: October 20, 2008
    Publication date: February 12, 2009
    Applicant: Fluke Corporation
    Inventors: Shounan Luo, Wang Yong