Abstract: A high-temperature superconductor fault current limiter elements (1) of standardized modular design and a high-temperature superconductor fault current limiter unit to protect an electrical application such as power network from damage in case of fault event.

Abstract: A quench detection device (or method) is provided that receives real-time information of concurrently monitored electrical characteristics of a high temperature superconducting (HTS) device, or any superconducting material, device, or system including low temperature superconductors, during operation. The quench detection device determines whether an electrical threshold is satisfied based on the received real-time information. The quench detection device detects a quench condition if the electrical threshold remains satisfied over a predetermined period of time or a predetermined successive number of times. If a quench detection is detected, the quench detection device sends a signal to terminate the operation of the HTS device.

Abstract: A method of controlling fault currents within a utility power grid is provided. The method may include coupling a superconducting electrical path between a first and a second node within the utility power grid and coupling a non-superconducting electrical path between the first and second nodes within the utility power grid. The superconducting electrical path and the non-superconducting electrical path may be electrically connected in parallel. The superconducting electrical path may have a lower series impedance, when operated below a critical current level, than the non-superconducting electrical path. The superconducting electrical path may have a higher series impedance, when operated at or above the critical current level, than the non-superconductor electrical path.

Abstract: Techniques for improving reliability of a superconducting fault current limiting system (SCFCL) are provided. In one particular exemplary embodiment, the techniques may be realized with a superconducting fault current limiting system (SCFCL) comprising: an input current lead and an output current lead, each current lead coupled to a power distribution/transmission network; a container; a superconductor contained in the container; a shunt disposed outside the container and in parallel with the superconductor; a cryogenic system configured to provide coolant into the container; and at least one sensor disposed near and configured to monitor at least one operating condition of at least one of the input current lead and the output current lead, the superconductor, and the shunt.

Abstract: This invention relates to a current limiter comprising a first circuit portion arranged in parallel with a second circuit portion, the first circuit portion comprising a superconductor element arranged in series with a switching arrangement, the second circuit portion comprising a load element, the superconductor element being disposed within a cooling chamber, and the cooling chamber and the switch being disposed within a vacuum chamber, wherein the switching arrangement comprises: a mechanical actuator which is operable between a closed condition in which current is conducted through the first circuit portion and an open condition in which current is diverted from the first circuit portion through the second circuit portion and a controller for monitoring and operating the switch.

Abstract: An apparatus 2 comprising a cryogenic chamber 4 and a galvanic input interface 6 to the cryogenic chamber 4 configured to receive a lower amplitude electric current 8. A converter 10 is located within the cryogenic chamber 4 and configured to convert the lower amplitude electric current 8, provided by the galvanic input interface 6, to a higher amplitude electric current 12 for supply to a load 14 within the cryogenic chamber 4. A controller 16 is configured to control the converter 10 and to detect the onset of quench by comparing the duration of the charge/discharge cycle of the convertor with a stored value. The controller 16 may also compare an instantaneous value of load current with a stored value of load current.

Abstract: A high voltage protection circuit for a non-tolerant integrated circuit is described herein. A non-tolerant integrated circuit may be a powered down integrated circuit or a low voltage tolerant integrated circuit, that may be exposed to a high voltage source such as an external circuit, device or power supply. The high voltage protection circuit includes a limiting transistor circuit, a control transistor circuit, and an isolation transistor circuit. The limiting transistor circuit limits or holds the voltage at the signal bump to be less than a voltage that can damage the circuit. The isolation transistor circuit disconnects input/output signal circuitry from normal protection circuitry. Both the limiting transistor circuit and the isolation transistor circuit are controlled by the control transistor circuit and are responsive to the power supply voltage being off.

Abstract: A superconducting high-field magnet coil system comprising several radially nested main coil sections (1, 2, 3, 4, 5) which are connected to each other in series in such a fashion that currents of the same direction flow through them during operation, wherein a first main coil section (EHS) is disposed radially further inward than a second main coil section (ZHS) and at least one intermediate main coil section (ZW) is disposed radially between the first and the second main coil section (EHS, ZHS), and with a superconducting switch (11) via which all main coil sections (1, 2, 3, 4, 5) can be superconductingly short-circuited in series, is characterized in that the first main coil section (EHS) and the second main coil section (ZHS) are directly successively series-connected and the first main coil section (EHS) and the second main coil section (ZHS) are bridged by a common quench protection element, which does not bridge the at least one intermediate main coil section (ZW).

Abstract: A new type of superconducting fault current limiter is disclosed, which can advantageously be used with high voltage transmission networks. The circuit is electrically connected to two terminals, which connect to the transmission network. The superconducting circuit is located within an enclosure or tank, which is electrically isolated from ground. Therefore, the voltage difference between the enclosure and the superconducting circuit, and between the enclosure and the terminals are significantly less than exist in current deployments. In some embodiments, the enclosure is electrically connected to one of the terminals, while in other embodiments, the enclosure is electrically isolated from the terminals. The circuit can be combined with other like circuits to address a wide range of current transmission network configurations.

Abstract: Techniques for protecting a superconducting (SC) article are disclosed. The techniques may be realized as an apparatus for protecting a superconducting (SC) article. The apparatus may comprise a porous sleeve configured to fit around the superconducting (SC) article. The porous sleeve may be made of non-conductive, dielectric material.

Abstract: A quench propagation arrangement for a superconducting magnet comprising a plurality of series-connected superconducting coils, the arrangement comprising: a positive supply line connected to cathodes of first diodes, of which respective anodes are connected to each respective node of the series connection of superconducting coils; a negative supply line connected to anodes of second diodes, of which respective cathodes are connected to each respective node of the series connection of superconducting coils; a number of heaters, respectively thermally connected to each of the superconducting coils and electrically connected between the positive supply line and the negative supply line; and a voltage limiter connected between the positive supply line and the negative supply line, in parallel with the heaters.

Abstract: A fan speed control circuit for controlling the rotation speed of a fan motor unit. The speed control circuit includes a resistor, a voltage stabilizing unit, a transistor and a thermal resistor. The resistor is connected to a power source of the fan motor unit, the voltage stabilizing unit is connected between the resistor and ground. The collector of the transistor is connected to the fan motor unit, the base is connected to a node between the resistor and the voltage stabilizing unit. The thermal resistor is connected between an emitter of the transistor and ground.

Abstract: Techniques for sub-cooling in a superconducting (SC) system is disclosed. The techniques may be realized as a method and superconducting (SC) system comprising at least one insulated enclosure configured to enclose at least a first fluid or gas and a second fluid or gas, and at least one superconducting circuit within the at least one insulated enclosure. The superconducting (SC) system may be sub-cooled using at least the first fluid or gas.

Abstract: This invention relates to a superconducting fault current limiter, including: an input segment of an input transformer core and an output segment of an output transformer, each segment having a first end and a second end; a length of superconductor which forms a winding around the input segment and a winding around output segment, wherein the windings are connected in series to form a closed loop; a cryostat in which the superconductor is housed; wherein each end of the input and output segments are exposed to the exterior of the cryostat.

Abstract: A method for current conditioning, comprising transporting a primary current (1) through a primary coil (2), coupling a secondary coil (3) to the primary coil (2) via a common magnetic flux, wherein the secondary coil (3) comprises a superconductor capable of quenching, with the quenching causing a transition of the superconductor from a low resistance superconducting state to a high resistance quenched state, and in the low resistance superconducting state of the secondary coil (3), guiding a major fraction (8) of the common magnetic flux of the primary coil (2) and the secondary coil (3) within a ferromagnetic medium (5a), is characterized by upon quenching, switching the common magnetic flux such that a major fraction (17) of the common magnetic flux is guided outside the ferromagnetic medium (5a) in the high resistance quenched state of the superconductor. An economic and efficient method for current conditioning is thereby provided which reduces harmonic distortions.

Abstract: In a superconducting coil, a parallel conductor includes a plurality of superconducting wires bundled and wound in a coil. The superconducting wires have at least two connections therebetween. A current source connected to the superconducting wires to form a loop via the superconducting wires and the connection to supply a current in the loop when a quench is detected. A superconducting magnet includes the superconducting coil, a persistent current switch connected to the superconducting coil, and a quench detector configured to detect quench occurring in the superconducting coil.

Abstract: A magnet system for generating a magnetic field may include a superconducting magnet, a switch, and a heater element thermally coupled to the switch. The superconducting magnet is structured to generate magnetic fields, and the switch includes a non-inductive superconducting current carrying path connected in parallel to the superconducting magnet. In general, the switch is structured to only carry a level of current that is a portion of the current required to obtain a full field by the superconducting magnet.

Abstract: In an emergency run down unit for a superconductive magnet assembly, a quench in the magnet is induced by the release of stored mechanical energy or by direct manual actuation.

Abstract: The invention relates to a supraconductive coil transition detector comprising means for disconnecting the detector directly before a coil discharge phase. The detector comprises a resistive divider (R1, R2) arranged in parallel on the supraconductive coil (1), the middle point A of the supraconductive coil and the middle point (B) of the resistive divider being connected to the two inlets of a threshold comparator. The connection means comprise switches (31-33) arranged on the connections between the coil and the detector, and means for opening said switches as soon as the comparator supplies a signal above a threshold.

Abstract: A current limiting device (30, 40, 50, 60) comprising for each phase of an AC supply a closed magnetic core (31) of reduced volume and mass having first and second pairs of opposing limbs (32a, 32b; 33a, 33b), and at least one AC coil (35a, 35b) enclosing opposing limbs (33a, 33b) of the magnetic core (31) and adapted for series connection with a load. A superconducting DC bias coil (34) encloses a limb) (32a, 32b) of the magnetic core (31) for saturating each of the opposing limbs (33a, 33b) in opposite directions by the bias coil (34). Under fault conditions, the AC flux in at least one limb counteracts the DC bias flux, bringing the limb out of saturation. Preferably, current is reduced in the DC bias coils thus bringing both opposing limbs of the core out of saturation.

Abstract: An energy dissipation arrangement for a cryogenically cooled superconductive magnet comprising a plurality of superconductive coils (10) connected in series and housed within a cryostat (24), comprising a superconducting switch (25) having a superconductive current path (28) in series with the superconductive coils (10); and a resistor (38), external to the cryostat, electrically connected in parallel with the superconductive current path (28) of the superconducting switch (25). The superconductive switch is arranged (26, 32, 30) to open in response to an electric current applied to an associated heater (26; 40).

Abstract: Disclosed herein is a Superconducting Fault Current Limiter (SFCL) for suppressing a bus voltage drop in an electric power system. A primary winding, a secondary winding, and a tertiary winding are wound around an identical iron core, and a superconductor is connected to any one of the primary winding and the secondary winding. A first switch is connected to any one of the primary winding and the secondary winding and is configured to be opened so as to separate a faulty section when a fault current is generated and to be shorted when the fault current is eliminated. A second switch is connected in series to the tertiary winding and is configured to be shorted so as to stably supply power when the fault current is generated and to be opened when the fault current is eliminated.

Abstract: A superconducting fault current limiter recovery system includes a superconducting fault current limiter, a shunt electrically coupled in parallel with the superconducting fault current limiter, and a bypass path also electrically coupled in parallel with the superconducting fault current limiter. The bypass path enables a load current to flow through the bypass path during a bypass condition. Thus, load current may be quickly reestablished to serve loads after a fault condition via the bypass path while a superconductor of the superconductor fault current limiter has time to return to a superconducting state after the fault condition.

Abstract: A superconducting fault current limiter (SCFCL) includes a cryogenic tank defining an interior volume, a superconductor disposed in the interior volume, and a voltage detector configured to detect a voltage drop across the superconductor and provide a voltage signal representative of the voltage drop. This voltage detector enables real time monitoring of a condition of the superconductor during steady state operation of the SCFCL. If the voltage drop exceeds an acceptable voltage drop, corrective action such as maintenance, repair, and/or replacement may be taken.

Abstract: An improved power transfer mechanism is disclosed, which is particularly beneficial in power transmission applications. The mechanism allows the SCFCL system to have more than one electrical reference. The use of hydraulic power simplifies the design of systems in which one part of the system is referenced to ground, while a second part of the system is referenced to a different voltage, typically much higher than ground. For example, the tank of the SCFCL system may not be connected to ground, while hydraulic power supply is referenced to ground. This embodiment is performed without the use of an electrically conductive path between the two parts of the system.

Abstract: A connector assembly of a superconducting fault current limiter includes a first superconducting tape element, an electrical connector electrically coupled to the first superconducting element at a first region of the electrical conductor, and a second superconducting tape element electrically coupled to the electrical connector in a second region of the electrical connector. The electrical connector comprises a unitary structure. The first superconducting tape element, the electrical connector, and the second superconducting tape element comprise may comprise a layer.

Abstract: A fault current limiter system including a fault current limiter and a variable shunt current splitting device. The current splitting device includes first and second conductive windings, wherein the first conductive winding is connected in parallel with the fault current limiter and is configured to carry current in a first direction. The second conductive winding is electrically connected in series with the fault current limiter and is configured to carry current in a second direction opposite to the first direction so that the reactance of the first winding is negated by the reactance of the second winding during steady state operation of the fault current limiter system. Thus, a first portion of a steady state current is conveyed through the fault current limiter and a second portion of the current is conveyed through the current splitting device. The steady state current load, on the fault current limiter is thereby reduced.

Abstract: A superconducting fault current limiter (SCFCL) includes a cryogenic tank defining an interior volume, a superconductor disposed in the interior volume, and a refrigeration system configured to adjust a temperature of the superconductor in response to a condition during a steady state operation of the SCFCL. A method of operating a SCFCL includes cooling a superconductor disposed within an interior volume of a cryogenic tank to a temperature less than a critical temperature of the superconductor, and adjusting the temperature of the superconductor in response to a condition during a steady state operation of the SCFCL.

Abstract: The present invention relates to a reclosing control system and method using a superconducting fault current limiter. The reclosing control system includes a superconducting fault current limiting device in which two circuits, each having a switch and a superconducting fault current limiter connected in series with each other, are connected in parallel with each other. A recloser is disposed between the superconducting fault current limiting device and a distribution line and is configured to control reclosing. The distribution line is connected to the recloser and is configured to transfer power to a load.

Abstract: A SCFCL system includes a first SCFCL, a second SCFCL, and a controller configured to control at least one switch to couple the first SCFCL to a power line between an AC source and a load, and to electrically isolate the second SCFCL from the power line during a first operating mode when the first SCFCL is in service and the second SCFCL serves as a spare. During the first operating mode, the second SCFCL, may be maintained in a latent standby state or an immediate standby state. The second SCFCL may be automatically switched into service to provide for fault current protection in case the first SCFCL needs to be taken out of service for maintenance, repair, or replacement.

Abstract: A superconducting article and method of fabrication are provided. The superconducting article includes a superconducting structure, which includes a superconducting conductor and multiple discrete overlay regions of higher heat capacity than the superconducting conductor. The multiple discrete overlay regions are disposed along a length of the superconducting conductor, in thermal contact with the superconducting conductor, and positioned to define a heat modulation pattern along the length of the superconducting structure. The multiple discrete overlay regions create a temperature distribution favorable to transition of the superconducting structure under load from a normal resistive state to a superconductive state by facilitating formation of a continuous superconducting path along the length of the superconducting structure.

Abstract: A modular design of a fault current limiter includes one ore more current limiting units 1 with one or more superconducting elements 2 and where standardized current limiting units 1 and standardized modular insulation housings 10 can be used for modular design of a fault current limiter.

Abstract: Between adjacent windings of a bifilar coil made of an HTS strip conductor in a resistive superconductive current limiter device, a spacer is provided which is transparent for a coolant. The spacer includes an electrically insulating support tape for sufficiently massive spacer elements attached thereon. The spacer elements are spaced and made of a material having high thermal conductivity. The spaces between the spacer elements form cooling channels for the coolant.

Abstract: A fault current limiter, with a superconducting device (1; 21; 31; 41; 51; 61; 71; 72) comprising a sequence of superconducting elements (2a-2f), each with an electrically conducting substrate (3a-3d), a superconducting film (5a-5d), and an electrically insulating intermediate layer (4a-4c) provided between the substrate and the superconducting film, wherein the superconducting films (5a-5d) of adjacent superconducting elements (2a-2f) of the sequence are electrically connected, in particular in series, wherein the electrically conducting substrate (3a-3d) of each superconducting element (2a-2f) of the sequence is electrically insulated from each electrically conducting substrate (3a-3d) of those adjacent superconducting elements (2a-2f) within the sequence whose superconducting films (5a-5d) are electrically connected in series with the superconducting film (5a-5d) of said superconducting element (2a-2f).

Abstract: A fault current limiter, with a superconducting device (1; 21; 31; 41; 51; 61; 71; 72) comprising a sequence of superconducting elements (2a-2f), each with—a substrate (3a-3d), —a superconducting film (5a-5d), and —an intermediate layer (4a-4c) provided between the substrate and the superconducting film, wherein the superconducting films (5a-5d) of adjacent superconducting elements (2a-2f) of the sequence are electrically connected, in particular in series, is characterized in that the substrates (3a-3d) of the superconducting elements (2a-2d) are electrically conducting substrates (3a-3d), wherein the electrically conducting substrate (3a-3d) of each superconducting element (2a-2f) of the sequence is electrically insulated from each electrically conducting substrate (3a-3d) of those adjacent superconducting elements (2a-2f) within the sequence whose superconducting films (5a-5d) are electrically connected in series with the superconducting film (5a-5d) of said superconducting element (2a-2f), and that the in

Abstract: A fault current limiter and a method for the production thereof has a superconducting device (1; 21; 31; 41; 51; 61; 71; 72) comprising a sequence of superconducting elements (2a-2f), each with an electrically conducting substrate (3a-3d), a superconducting film (5a-5d) and an electrically insulating intermediate layer (4a-4c) provided between the substrate and the superconducting film. The superconducting films (5a-5d) of adjacent superconducting elements (2a-2f) of the sequence are electrically connected, in particular in series, wherein the electrically conducting substrate (3a-3d) of each superconducting element (2a-2f) of the sequence is electrically insulated from each electrically conducting substrate (3a-3d) of those adjacent superconducting elements (2a-2f) within the sequence whose superconducting films (5a-5d) are electrically connected in series with the superconducting film (5a-5d) of said superconducting element (2a-2f).

Abstract: The present invention discloses a bi-direction driver IC and a method for bi-directionally driving an object. The method comprises: providing a first and a second integrated circuit (IC) chips, coupled with an object to be driven, wherein each of the first and second IC chips is capable of single-directionally driving the object; providing a reverse current path in each of the first and second IC chips; driving the object in a first direction by the first IC chip, wherein current flows through the reverse current path in the second IC chip; and driving the object in a second direction by the second IC chip, wherein current flows through the reverse current path in the first IC chip.

Abstract: A superconducting magnet assembly comprising a plurality of superconducting magnet coil portions forming a coil series circuit to provide a magnetic field, a power supply to supply power to the plurality of superconducting magnet coil portions during a magnet ramp mode of operation, and a ramp switch coupled to the superconducting magnet coil portions, wherein the ramp switch is configured to be open during a magnet ramp mode and closed during a persistent mode. A dump resistor is disposed externally to the vessel and is connectable by the ramp switch to the superconducting magnet coil portions. Further, a controller is coupled to at least one superconducting magnet coil portion and the ramp switch and is configured to detect a quench onset condition in the at least one superconducting magnet coil portion and to open the ramp switch upon detection of the quench onset condition in order to dump magnet energy.

Abstract: A superconducting article is provided which incorporates an early quench detection facility. The superconducting article includes a first superconductive segment and a second superconductive segment, along with a magnetic field sensor(s). The magnetic field sensor(s) is disposed to monitor relative change in strength of a net magnetic field generated by a first current passing through the first superconductive segment and a second current passing through the second superconductive segment. A relative change in strength of the net magnetic field indicates degradation of a critical quench current of the first superconductive segment or the second superconductive segment, caused for example, by formation of one or more hot-spots or quench regions in the first or second superconductive segment. The indication of degradation is thus obtained prior to complete superconductive segment quenching.

Abstract: A high-temperature superconductor fault current limiter elements (1) of standardized modular design and a high-temperature superconductor fault current limiter unit to protect an electrical application such as power network from damage in case of fault event.

Abstract: An improved power transfer mechanism is disclosed, which is particularly beneficial in power transmission applications. The mechanism allows the SCFCL system to have more than one electrical reference. The use of hydraulic power simplifies the design of systems in which one part of the system is referenced to ground, while a second part of the system is referenced to a different voltage, typically much higher than ground. For example, the tank of the SCFCL system may not be connected to ground, while hydraulic power supply is referenced to ground. This embodiment is performed without the use of an electrically conductive path between the two parts of the system.

Abstract: The present invention relates to a system (100) for creating a magnetic field via a superconducting magnet (102) intended to produce said magnetic field. The system (100) according to the invention comprises a first branch including the superconducting magnet (102) formed by a coil inductance (L?) in series with a residual resistance (R?2), a second branch comprising a protection resistance (R?3) and a third branch comprising a power source (103). Furthermore, the system comprises a fourth branch formed by a resistance (R?1) mounted in series with a current-limiting superconducting device (106) switching from a low-resistance state to a high-resistance state when the current passing therethrough exceeds a breaking current, said first, second, third and fourth branches being mounted in parallel.

Abstract: An alternating current system 10 has a primary circuit 11 which forms a primary winding 18 on a core 16. A secondary winding 24 is connected with a current source 26 or, alternatively, with an impedance 60. The core 16 is threaded by a superconducting coil 20 having a current source 22. In normal use, current in the coil 20 provides a DC bias level of flux in the core 16, and the source 26 is varied to maintain substantially constant flux, thereby minimising losses in the primary circuit 11. In fault conditions, current in the coil 20 is reduced or removed to increase voltage losses across the coil 18, thereby limiting fault current. The impedance 60 can also be switched into circuit, creating further current limiting by virtue of the transformer effect of the windings 18, 24.

Abstract: A superconducting magnet assembly comprises a superconducting magnet which, under working conditions, generates a magnetic field in a working volume. The superconducting magnet is connected in parallel with a series combination of a superconducting fault current limiter and a resistor, and with a DC power source. Under working conditions, the magnet can be energized by the power source to generate a desired magnetic field in the working volume.

Abstract: The device has a quenchable superconductor (1), a first metallic member (2) electrically coupled with the quenchable superconductor (1), a second metallic member (3) electrically coupled to the first metallic member (2). The first metallic member (2) is thermally and electrically coupled with the quenchable superconductor (1) due to their direct surface contact. The superconducting device has a second metallic member (3) with a resistive element (4) and an electrical coupling (5) with the first metallic member (2). The resistive element (4) of the second metallic member (3) is thermally decoupled from the first metallic member (2). The first metallic member (2) has a substantially higher electrical resistance compared to the second metallic member (3).

Abstract: A superconductor for mitigating the effects of local current disruptions in a superconducting filament. The superconductor comprises superconducting filaments covered by a medium in electrical communication with the filaments. The covering medium has anisotropic conductivity, the conductivity in a direction substantially aligned with the filaments being selected to stabilize the superconductor near the critical temperature, and the conductivity of the covering in a direction substantially perpendicular to the filaments being selected to permit controlled current sharing between the filaments, especially when a filament is compromised, while simultaneously limiting alternating current (ac) losses. In various embodiments, the covering comprises a wire mesh having longitudinal wires made of a first material having a first conductivity, and transverse wires made of a second material having a second conductivity, different from the first conductivity.

Abstract: A superconducting magnet includes at least one superconducting coil and a quench protection circuit electrically coupled to said at least one coil in parallel. The circuit includes at least one quench heater assembly thermally coupled to the at least one coil, and at least one superconducting current limiter electrically connected in series with the at least one quench heater assembly. The superconducting current limiter has a superconducting state with zero resistance, and a normal state with a normal resistance to decrease an electric current flowing through the quench heater assembly.

Abstract: An improved persistent current switch design and method of operation are disclosed. By way of example, a persistent current switch circuit comprises a heating element and a switch element located proximate to the heating element, the switch element being substantially formed from a material (by way of example only, titanium) which exhibits a superconducting temperature value below a superconducting temperature value exhibited by a material (by way of example only, aluminum) used to provide a connection to the switch element. The switch element is responsive to the heating element such that the heating element is used to control whether or not the switch element is in a superconducting state. The switch element may also have a folded geometry. Such persistent current switches exhibit low power and low inductance.

Abstract: The present invention provides devices and methods for testing the electrical performance of thin-film transistor backplane arrays and protecting thin-films during testing and handling.

Abstract: A magnet system for generating a magnetic field may include a superconducting magnet, a switch, and a heater element thermally coupled to the switch. The superconducting magnet is structured to generate magnetic fields, and the switch includes a non-inductive superconducting current carrying path connected in parallel to the superconducting magnet. In general, the switch is structured to only carry a level of current that is a portion of the current required to obtain a full field by the superconducting magnet.