Abstract: A method and an apparatus for use in an earth-fault protection in a three-phase electric network, the apparatus configured to detect a phase-to-earth fault in the three-phase electric network, to determine for each of the three phases of the three-phase electric network a phase current during the detected phase-to-earth fault or a change in the phase current due to the detected phase-to-earth fault, to determine an estimate of an earth-fault current on the basis of the determined phase currents or on the basis of the determined changes in the phase currents, to determine, if the estimate of the earth-fault current represents an actual earth-fault current or an apparent earth-fault current, and to determine, in response to determining that the estimate of the earth-fault current represents the actual earth-fault current, that the estimate of the earth-fault current is valid.

Abstract: A current transformer assembly includes a first current transformer, a plug, a first wire and a second wire between the plug and the first current transformer adapted to transmit a measurement of the first current transformer; and a memory chip adapted to store a first scale factor of the first current transformer.

Abstract: A method can include an integrated circuit device, determining if first communication circuits are operating in a first mode that wirelessly receives data at a first rate or a second mode that wirelessly receives data at a second rate that is lower than the first rate. If the first communication circuits are operating in the second mode, transmitting signals with the second communication circuits at a first power level, and if operating in the first mode, transmitting signals with the second communication circuits at a second power level that is lower than the first power level. In the first mode, X symbols per data bit are received and in the second mode, Y symbols per data bit are received, where X<Y. Corresponding devices and methods are also disclosed.

Abstract: A field device for automation, comprising: a housing; arranged within the housing, a field device electronics, to which a maximum power is made available via a two-wire line; a memory element for storing of data, wherein the memory element, for exchange of data and/or for energy supply, is electrically connected with the field device electronics and, at least in the case of storing the data, requires a power, which at least at times is higher than the maximum power available via the two-wire line; a first, NFC antenna, which is adapted wirelessly to receive an auxiliary energy and to provide the auxiliary energy to the field device electronics; a second antenna, which is adapted to communicate the data wirelessly and to exchange such with the field device electronics; wherein the field device electronics is adapted to supply the memory element with the auxiliary energy.

Abstract: A circuit arrangement for reducing a magnetic unidirectional flux component in a core of a transformer includes a measuring device that provides a sensor signal corresponding to the magnetic unidirectional flux component, a compensation coil magnetically coupled to the core of the transformer, and a semiconductor switching device which is electrically arranged in a current path in series with the compensation coil to feed a current into the compensation coil, such that current is directed opposite the unidirectional flux component, where the semiconductor switching device is controlled via a control signal provided by a controller, and includes an inductive voltage divider having a first impedance component arranged in a current circuit in series with the compensation coil and the semiconductor switching device and a second impedance component arranged in parallel with the semiconductor switching device, where the first impedance component is connected in parallel with a parallel resonant circuit.

Abstract: A converter arrangement has a converter which can be switched between an AC network and a DC voltage circuit and which has power semiconductor valves that extend between AC voltage connections and DC voltage connections. Each power semiconductor valve has a series connection of bipolar submodules that in turn include power semiconductor devices. The arrangement further includes a star point reactor which is arranged on the AC voltage side of the converter and has impedance coils that are connected to a grounded neutral point. In order to better balance the voltages in the DC circuit, the impedance coils have a common coil core.

Abstract: One embodiment provides a method, including: utilizing at least one processor to execute computer code that performs the steps of: receiving forecasted geomagnetic information caused by solar activity; estimating, using the forecasted geomagnetic information, a geomagnetically induced potential for each of a plurality of transformers operatively coupled to a transmission line, wherein the geomagnetically induced potential is created by geomagnetic disturbances identified using the forecasted geomagnetic information; determining an optimized compensation voltage to be applied to at least one of the plurality of transformers operatively coupled to the transmission line, wherein the optimized compensation voltage comprises a voltage that reduces the potential difference, caused by the induced potential, between neutral lines of the plurality of transformers; and applying the optimized compensation voltage to at least one of the plurality of transformers operatively coupled to the transmission line.

Abstract: A device for reducing a magnetic unidirectional flux component in the core of a three-phase transformer includes at least one compensation winding, which is magnetically coupled to the core of the three-phase transformer, a switch arranged electrically in a current path in series with the at least one compensation winding to feed current into the winding, where the effect of the current is directed opposite to the unidirectional flux component, and an apparatus for limiting current arranged electrically in a current path in series with the at least one compensation winding, and where two compensation windings are provided on different legs of the core of the three-phase transformer such that a greater reduction of the magnetic unidirectional flux component is achieved.

Abstract: Embodiments describe a charging component for an electronic device that includes an interface surface comprising a portion of an external surface of a housing of the electronic device; a plurality of contacts positioned at the interface surface and exposed for making contact with contacts of a connector; one or more sensors for detecting a separation event; an inductor coil positioned proximate to the interface surface, wherein a central axis of the inductor coil is perpendicular to at least a portion of the interface surface; and a processor coupled to the inductor coil and the one or more sensors, wherein the processor is configured to change an operation of the inductor coil based at least in part on a measurement from the one or more sensors.

Abstract: Methods and apparatus for flux cancellation includes first and second inductors. A system cam include first and second inductors and a layer of magnetic material disposed between the first inductor and the second inductor. In embodiments, when the inductors are driven with a respective oscillating current, at least a portion of magnetic flux generated by the first inductor is substantially canceled by at least a portion of magnetic flux generated by the second inductor in the layer of magnetic material.

Abstract: An arrangement for reducing a magnetic unidirectional flux component in the core of a transformer includes a measurement apparatus which provides a measurement signal corresponding to the magnetic unidirectional flux component, a compensation winding magnetically coupled to the core of the transformer, wherein magnetic flux flowing in the core induces a voltage in the compensation winding, a switch device arranged electrically in series together with the compensation winding in a current path, a control device which controls the switch device via a control parameter, where the switch unit comprises a magnetic core and a winding arrangement which is magnetically coupled to the magnetic core, and the control parameter is supplied to the winding arrangement such that the magnetic saturation state of the core is variable, whereby the conductive state of the switch unit can be produced.

Abstract: An inverter includes a plurality of inverter legs that each includes first, second, and third switches. A first control line connected to the first switch receives a first control signal. A second control line connected to the second switch receives a second control signal. A third control line connected to the third switch receives the first control signal. The first, second, and third switches are connected sequentially in series. A first connector line is connected between the first switch and the second switch and to a first winding of an electric machine. A second connector line is connected between the second switch and the third switch and to a second winding of the electric machine. The second control signal is complementary to the first control signal.

Abstract: A current sensor arrangement for measuring an effective primary current in a primary conductor having a magnetic core for magnetic coupling of the primary conductor to a secondary conductor and a controlled voltage source connected to the secondary conductor and configured to apply a voltage with adjustable polarity to the secondary conductor so that a secondary current passes through the secondary conductor. A measurement and control unit is coupled to the secondary conductor and configured to generate a measuring signal that represents the secondary current, to continuously detect the occurrence of magnetic saturation in the core, and to reverse the polarity of the voltage upon the detection thereof in order to reverse magnetization of the core. Furthermore, the measurement and control unit is configured to evaluate a spectrum of the measuring signal and determine a frequency of a current passing through the primary conductor based on the spectrum.

Abstract: The invention relates to an electric energy storage system, comprising an inverter (6), several associations (21, 22), of an electric energy storage unit (1, 2) in series with a bidirectional chopper (3, 4), connected in parallel to a same input of the inverter (6), on the side of their chopper (3, 4), characterized in that at least one bidirectional chopper (3, 4), associated with an electric energy storage unit (1, 2) that can be charged and discharged asymmetrically, is sized asymmetrically for the charge and discharge of said associated storage unit (1, 2).

Abstract: A transformer includes multiple differential ports and first and second transformer windings. The first transformer winding includes a first transformer half-winding coupled to a first differential port of the differential ports. The first transformer winding also includes a second transformer half-winding coupled to a second differential port of the differential ports. An amplifier system that has a transformer is also provided. The amplifier system includes a first and a second stage amplifier. The first stage amplifier includes a first and a second amplifier. The second stage amplifier includes a third and a fourth amplifier. The transformer is coupled between the first stage amplifier and the second stage amplifier, where the transformer has a primary loop and a secondary loop. The primary loop of the transformer may be configured to receive differential signals of the first amplifier. A method for fabricating a transformer is also provided.

Abstract: Systems and methods for concurrent wireless power transfer and data transmission are provided. A constraint encoder receives data bits for communication to a mobile device and encodes the data bits onto a transmit signal. The constraint encoder specifies signal constraints that cause the transmit signal to have a peak-to-power-average ratio (PAPR) during a given time interval sufficient to provide wireless power transfer to the mobile device. The system also includes a signal generator coupled to the constraint encoder. The signal generator generates the transmit signal according to the signal constraints. The system further includes a transmitter coil that is coupled to the signal generator. The transmitter coil is configured to transmit the transmit signal that has been encoded with the data bits to receiver coils of the mobile device. The encoded transmit signal is able to provide wireless power transfer and the encoded data bits to the mobile device.

Abstract: A remote energy transfer system is provided that is capable of wirelessly transmitting data and power through barriers. Generally, the remote energy transfer system comprises at least one power antenna, at least one data antenna, and at least one link controller operatively coupled to the power antenna and the data antenna. The link controller can be configured to at least partially control the energy transfer from the power antenna and the data transfer of the data antenna.

Abstract: Disclosed is a communication apparatus comprising: a communication section which performs communication in an ASK modulation format with an RFID tag; and a control section which sets a modulation degree of the ASK modulation of the communication section to a large degree when polling of the RFID tag is performed by the communication section and which sets the modulation degree to a small degree when response information is received from the RFID tag through the communication section.

Abstract: A magnetic flux pad for generating or receiving magnetic flux has two pole areas (11, 12), a permeable core (14) and a coil (16) wound about the core. The pad allows useable flux to be generated at a significant height above a surface of the pad.

Abstract: A method for linearizing voltage transmission through a transformer including a magnetic core and, input and output windings. A measurement signal is supplied to the input winding at a first frequency and an output signal is measured at the output winding of the transformer, wherein the voltage of the measurement signal may be so low that the transformer operates in a non-linear region. The method includes, for a conditioning signal, selecting a second frequency different from the first frequency, defining an amplitude value of the conditioning signal and supplying the conditioning signal to the input winding at the second frequency with the defined amplitude value so that the transformer operates in its linear region.

Abstract: An apparatus and technique that reduces induced cross-talk current between transformer windings. The apparatus includes a transformer having a first secondary winding that provides a first voltage relative to earth ground, a second secondary winding that provides a second voltage relative to floating ground, and a shield disposed between the first and second secondary windings. A correction circuit connected to the first secondary winding is configured to generate a correction voltage. The correction voltage drives a shield to induce a correction current into the second secondary winding to reduce cross-talk current induced between the first and second secondary windings.

Abstract: In accordance with the invention there is also provided a voltage combiner comprising: a transformer having a first and second winding each having a first and second tap; and an inductor connected between the first and second taps of the second winding, wherein: the first tap of the first winding is adapted for connection to a first voltage, the first tap of the second winding is adapted for connection to a second voltage, and the second tap of the second winding is adapted to provide an output being the first and second voltages combined, and further wherein: the inductor is adapted to provide a bypass path for the current associated with the second voltage.

Abstract: A method for linearizing voltage transmission through a transformer including a magnetic core and, input and output windings. A measurement signal is supplied to the input winding at a first frequency and an output signal is measured at the output winding of the transformer, wherein the voltage of the measurement signal may be so low that the transformer operates in a non-linear region. The method includes, for a conditioning signal, selecting a second frequency different from the first frequency, defining an amplitude value of the conditioning signal and supplying the conditioning signal to the input winding at the second frequency with the defined amplitude value so that the transformer operates in its linear region.

Abstract: An electrical transformer with unidirectional flux compensation is provided. The transformer includes a soft magnetic core on which a primary winding arrangement, a secondary winding arrangement, and a compensation winding arrangement are arranged. The compensation winding arrangement is connected to a current control device which feeds a compensation current into the compensation winding arrangement using a control signal. A magnetic field measuring device measures the magnetic field in the core of the transformer or the stray magnetic field that closes outside the core via an air path and provides the control signal.

Abstract: The present invention is a DC-DC converter characterized by including a switch element that is provided between one end of a DC power source and one end of a load and turns ON and OFF current input from the DC power source, an inductance element that is provided between one end of the switch element on a load-side end and includes a doughnut-shaped magnetic core and a conductive wire wound around the magnetic core, a commutation switch provided between a node between the switch element and the inductance element and a ground potential, and a capacitance element provided between a node between the inductance element and the load and the ground potential, wherein a magnetic flux density of the magnetic core varies partially.

Abstract: The present invention discloses a flux linkage compensator, which applies to an UPS system and comprises a load transformer flux linkage observer, a compensation voltage command generator, and a flux linkage command generator. The load transformer flux linkage observer generates a load transformer flux linkage signal. The flux linkage command generator generates a flux linkage command signal. The difference between the load transformer flux linkage signal and the flux linkage command signal forms a flux linkage deviation signal. The compensation voltage command generator generates a voltage compensation signal to make the flux linkage deviation signal approach zero. Thereby, the flux linkage compensator can compensate for the flux linkage deviation occurring in starting the UPS system. Thus, the present invention can perform voltage compensation fast and reliably and inhibit the inrush current effectively.

Abstract: A method is provided for controlling a resonant circuit (1) of an ICPT system. The resonant circuit has a controlled variable reactance (2), and a predetermined perturbation is introduced in the magnitude of variable reactance. The change in a property of the resonant circuit in response to the perturbation is sensed, and the variable reactance is varied to alter the resonant frequency of the circuit in response to the sensed change.

Abstract: A saturation control unit for an interphase transforming unit is provided. The interphase transforming unit has a primary coil and a secondary coil which are magnetically coupled via a magnetic core member. The saturation control unit includes a minimum detecting unit and a maximum detecting unit. The minimum detecting unit detects a minimum value of a magnetizing current of the interphase transforming. The maximum detecting unit detects a maximum value of the magnetizing current. A saturation estimating unit is provided for estimating an offset value of the magnetizing current. A saturation control signal generating unit is provided for generating a saturation control signal for the interphase transforming unit based on the detected minimum value, the detected maximum value, and the estimated offset value.

Abstract: A method for voltage stabilization of an electrical power network system including a producing power network system side, a consuming power network side including a power load, a power transmission line with an impedance ZLN, a transformer and an on-line tap changer added to the transformer. The impedance of the line is measured in case of dynamic instabilities. A transformer ratio n is controlled by changing a voltage reference Vref of the on-line tap changer. The voltage reference is changed according to a feed forward compensation from the impedance of the line.

Abstract: The present invention discloses a flux linkage compensator, which applies to an UPS system and comprises a load transformer flux linkage observer, a compensation voltage command generator, and a flux linkage command generator. The load transformer flux linkage observer generates a load transformer flux linkage signal. The flux linkage command generator generates a flux linkage command signal. The difference between the load transformer flux linkage signal and the flux linkage command signal forms a flux linkage deviation signal. The compensation voltage command generator generates a voltage compensation signal to make the flux linkage deviation signal approach zero. Thereby, the flux linkage compensator can compensate for the flux linkage deviation occurring in starting the UPS system. Thus, the present invention can perform voltage compensation fast and reliably and inhibit the inrush current effectively.

Abstract: transformer includes a soft magnetic core on which a primary winding arrangement, a secondary winding arrangement, and a compensation winding arrangement are arranged. The compensation winding arrangement is connected to a current control device which feeds a compensation current into the compensation winding arrangement using a control signal. A magnetic field measuring device measures the magnetic field in the core of the transformer or the stray magnetic field that closes outside the core via an air path and provides the control signal.

Abstract: The invention relates to a transformer (10) for balancing the current in an AC circuit, comprising a primary winding (12), a secondary winding (14) and a main inductance (16). The transformer is characterized in that a capacitive component is connected in parallel to the primary winding (12) or to the secondary winding (14), whose capacitance value is determined such that the reactive current IL brought about by the main inductance (16) is substantially compensated. A transformer of this kind can preferably be employed in current balancing circuits as used, for example, in systems for backlighting LCD displays.

Abstract: An inductive power transfer system includes a base unit comprising a first inductive element for providing input power to a second inductive element of a target unit providing output power, a positioning structure provided on at least one of the base unit and the target unit for removably positioning the second inductive element at a predetermined orientation and distance relative to the first inductive element, a switch element configured for selectively applying a time varying electric current to the first inductive element to produce a time varying magnetic field for inducing an electric current in the second inductive element, and a control circuit for monitoring one parameter indicative of an efficiency of power transfer and automatically selectively adjusting at least one characteristic of the time varying electric current responsive to the parameter to maximize an efficiency of power transfer from the base unit to the target unit.

Abstract: A power converter having input and output nodes and a method of operating the same. In one embodiment, the power converter includes a switching circuit including first, second and third active phase legs. Each of the first, second and third active legs includes a first switch coupled to one of the input nodes and a second switch coupled to another of the input nodes and has a common switching node therebetween. The power converter further includes a magnetic device including first, second and third primary windings, and first, second and third secondary windings. The first, second and third primary windings are coupled to the common switching node of the first, second and third active phase legs, respectively. The power converter still further includes a rectifier including first, second and third rectifier elements interposed between the first, second and third secondary windings, respectively, and one of the output nodes.

Abstract: A communication transformer for power line communication includes a magnetic core, a plurality of transfer-purpose windings wound on the magnetic core, and an additional winding. The additional winding is wound on the magnetic core in such a manner that the additional winding is positioned between the plurality of transfer-purpose windings, and does not contribute in signal transfer operations. The communication transformer is arranged such that a half way portion of the additional winding along a length direction thereof is electrically connected to a constant potential.

Abstract: A system for managing electrical consumption includes a connecting means for connection to an incoming power supply of a facility, for connection in parallel, including a hot line and a neutral line, and at least one ground. The following components are connected between the hot line and the neutral line. They are connected in the order of at least one front capacitor of predetermined capacitance, at least one front arc suppressor, at least one front metal oxide varistor line transient voltage surge suppressor having a predetermined number of joules capability to suppress undesired power spikes, at least two inductor/metal oxide varistor iterative transformers, at least a second capacitor of its own predetermined capacitance, at least one metal oxide varistor having a predetermined number of joules capability and at least two capacitors, each having its own predetermined capacitance different form one another.

Abstract: An compensated voltage transformer includes a voltage transformer. The voltage transformer includes a primary winding that receives a supply voltage, a meter winding that generates a first voltage based on a first turns ratio between the primary winding and the meter winding, and a power winding that generates a second voltage based on a second turns ratio of the primary winding to the power winding. A current transformer includes a primary winding and a secondary winding. The primary winding carries a load current that flows through the power winding and the secondary winding connects to the meter winding.

Abstract: A two-step charger includes an AC/DC power supply, a transformer, a compensator, a controller, a comparator and an isolating controller. The comparator detects whether a battery is connected to the transformer. If so, a command voltage of the charger is set at a high level. Since the battery voltage is lower than the command voltage, the controller orders the compensator to send out a compensating current. The current entering the primary side of the transformer is increased to promote the output current from the secondary side of the transformer. Once the comparator detects that the battery reaches as high as the charger, the command voltage is adjusted to a low level. The controller orders the compensator to stop outputting the compensating current. Therefore, a larger current can speed up battery charging. Once the battery is fully charged, the charging voltage is lowered to avoid high temperature.

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.

Abstract: An untethered device is configured to inductively couple to a source device, which generates a varying magnetic field having a fixed frequency. The untethered device includes a tunable resonant circuit having a resonance frequency and configured to generate a supply voltage for the untethered device in response to the varying magnetic field. The untethered device further includes a frequency control circuit coupled to the tunable resonant circuit and configured to produce a control signal using signals developed within the tunable resonant circuit. The control signal is useable to adjust the resonance frequency of the tunable resonant circuit to the fixed frequency of the source device.

Abstract: A power converter having input and output nodes and a method of operating the same. In one embodiment, the power converter includes a switching circuit including first, second and third active phase legs. Each of the first, second and third active legs includes a first switch coupled to one of the input nodes and a second switch coupled to another of the input nodes and has a common switching node therebetween. The power converter further includes a magnetic device including first, second and third primary windings, and first, second and third secondary windings. The first, second and third primary windings are coupled to the common switching node of the first, second and third active phase legs, respectively. The power converter still further includes a rectifier including first, second and third rectifier elements interposed between the first, second and third secondary windings, respectively, and one of the output nodes.

Abstract: The present invention relates a system for compensating for a voltage dip and undervoltage containing a primary side and secondary side transformer, a voltage dip/swell detector, and a level detector/switch selector device, wherein the secondary side of the transformer possesses a minimally sufficient number of taps to allow the system to be modified to meet supply voltage dips. The system, in particular, allows for long term compensation of voltage dips and quick adjustment of load voltage, usually within one cycle. Methods of using the present invention are also presented.

Abstract: An apparatus for controlling the power flow in a high voltage network. A phase shifting transformer includes a tap changer.

Abstract: The present the invention provides power supplies and circuitry for powering high-voltage devices.

Abstract: Methods and apparatus for supplying power for use in metering electrical energy over a wide range of voltages with a single meter are disclosed. The wide ranging meter includes a processing unit for processing divided input voltage and a current component in order to determine electrical energy metering values. The processing unit is operable in response to supply voltages. A power supply, connected to receive the undivided voltage component, generates the supply voltages over the wide dynamic range. It is especially preferred for the power supply to include a transformer having first, second and third windings, wherein the undivided voltage component is provided to the first winding and wherein the second winding defines the output of the power supply. A switching member is connected to the first winding for permitting and preventing the flow of current in response to a control signal. A control member generates the control signal in response to the output of the power supply.

Abstract: Circuits for shortening a rise time of a load include a main pulse transformer coupled to a load, an auxiliary pulse transformer coupled to the load, and a diode connected between the auxiliary pulse transformer and the main pulse transformer. The main pulse transformer delivers a main pulse to the load. The auxiliary pulse transformer delivers an auxiliary pulse to charge the capacitance associated with the load. The diode isolates the auxiliary pulse transformer from the main pulse. By charging the capacitance in this manner, a rise time of the main pulse is shortened and ringing of the main pulse on the load is reduced.

Abstract: Process and device for compensating the low frequency magnetic field in an inductive signal coupling unit. According to the invention the coupling unit comprises a ferromagnetic core (30) which encloses a conductor through which a low frequency current (1) is circulating in order to inject thereon a high frequency signal. Current (1), circulating through the conductor or the magnetic field (3) produced in the coupling unit, is detected, and a compensating current is obtained based on the value obtained in the detection carried out, and the compensating current obtained in the coupling unit is injected through a low pass filter (9) to produce a magnetic field (4) equal and opposite to the produced by current (1) of the conductor in the coupling unit, and thereby avoiding the saturation of the magnetic core (30) without adding insertion loss.

Abstract: A capacitive voltage transformers for distribution of the power from 10 kv high potential line, includes a insulating column with a high potential terminal, a ground terminal and capacitors C1 and C2 in series connection. The column is filled with oilless dry filler. The capacitors C1 and C2 formed by a plurality of separated metallized film capacitors respectively in series or in parallel connection. At the tapping point between the capacitors there is a leading-out terminal of the secondary voltage which is connected to an induction transformer L in parallel. The transformer includes a frame with “C” shaped iron cores and windings wound around the cores. There is an over-voltage protector P connected in parallel between the tapping point and ground. A capacitive voltage divider is integrally combined with the transformer to provide a small volume, low cost device with a savings in materials.

Abstract: A current sensor (1) is provided with low-pass filters (17 and 18) for stabilizing the pulse-duration modulated compensation signal. The current sensor is also provided with an additional RC element (40). Furthermore, a limiting means consisting of Zener diodes (44) and an ohmic resistance (45) is provided for suppressing fast current transients.

Abstract: A piezoelectric ceramic transistor is formed from a single-layered or multi-stacked layers piezoelectric ceramic voltage transformer and a capacitor, the capacitor being series connected to an input terminal of the piezoelectric ceramic voltage transformer to prevent electric power and prevent loss due to feedback, thereby compensating and increasing vibrations of the piezoelectric ceramic voltage transformer. Alternatively, the above connection scheme is achieved by either serial connecting a capacitor between a power output of the transformer and a load terminal, or parallel connecting a first capacitor to a power input of the transformer while a second capacitor is series connected between a power output of the transformer and the load terminal to obtain an increased power and thereby increasing the load current.