Abstract: This disclosure relates to techniques for codec selection for voice calls. A wireless device may initiate a voice call and may determine one or more link quality indicators. Based at least in part on the one or more link quality indicators, the wireless device may select a codec for the voice call.

Abstract: Disclosed herein is an analog-to-digital converter (ADC) for converting an input analog voltage to an output digital code, the ADC comprising a first node of the input analog voltage; nodes of a plurality of reference voltages; a plurality of comparators, inputs of each comparator being coupled to the first node and a node of a corresponding reference voltage of the plurality of reference voltages; a logic circuit block for receiving outputs of the plurality of comparators and generating the output digital code; and a voltage stabilizer, terminals of the voltage stabilizer being coupled with the first node and a node of a first reference voltage among the plurality of reference voltages.

Abstract: An inductive capacitive structure including a first substrate, a first conductive line over the first substrate, a first shielding layer over the first substrate and a second substrate over the first substrate.

Abstract: A superconducting integrated circuit may include a magnetic flux transformer having an inner inductive coupling element and an outer inductive coupling element that surrounds the inner inductive coupling element along at least a portion of a length thereof. The magnetic flux transformer may have a coaxial-like geometry such that a mutual inductance between the first inductive coupling element and the second inductive coupling element is sub-linearly proportional to a distance that separates the first inner inductive coupling element from the first outer inductive coupling element. At least one of the first inductive coupling element and the second inductive coupling element may be coupled to a superconducting programmable device, such as a superconducting qubit.

Abstract: A thin film inductor with top and bottom pole pieces that are mechanically connected to each other at at least two via zones, to create a magnetically permeable yoke that defines at least one interior space. Enclosed portion(s) of a winding member pass through the interior space(s) of the yoke. The enclosed portion(s) of the winding member define an axial direction and a transverse direction. The pole pieces extend beyond the via zones in the axial and/or transverse direction. The extended pole pieces improve magnetic performance of the thin film inductor, by effectively moving pole piece edges away from locations of high magnetic flux density.

Abstract: A fault current limiter for limiting current faults in an electrical network comprising: a series of phase coils located adjacent a superconductive coil for fault current limiting phase faults within the network; a series of neutral coils located adjacent the superconductive coil for fault current limiting neutral earthing faults in the electrical network.

Abstract: A system and method for protecting a superconductor from a quench condition. A quench protection system is provided to protect the superconductor from damage due to a quench condition. The quench protection system comprises a voltage detector operable to detect voltage across the superconductor. The system also comprises a frequency filter coupled to the voltage detector. The frequency filter is operable to couple voltage signals to a control circuit that are representative of a rise in superconductor voltage caused by a quench condition and to block voltage signals that are not. The system is operable to detect whether a quench condition exists in the superconductor based on the voltage signal received via the frequency filter and to initiate a protective action in response.

Abstract: In a current limiter for limiting currents in case of a fault including an additional device comprising an additional electric valve connected in series and being conductive in the same direction as the associated main valve, two series-connected valve branches arranged in opposition bypass two series connected current limiting inductors and both additional valves are bypassed by a similar passively complex connection for limiting current in the case of a fault, wherein the current limiter is not noticeable during normal operation, but, in the event of a fault, effectively limits the short circuit to a predetermined extent.

Abstract: A superconducting current limiting device (30) comprising: an interconnected high magnetic permeability structure including a central core (50) interconnected to at least a first and second arm (31, 32) branching off therefrom; a superconductive coil (33, 34) surrounding the central core for biasing the central core; a first alternating current coil (36, 37) surrounding the first arm and interconnected to an alternating current source; a second alternating current coil (38, 39) surrounding a second arm and interconnected to an alternating current load; the first and second alternating current coils being magnetically coupled to the central core wherein the device operates so as to limit the current passing through the device upon the occurrence of a fault condition in the load.

Abstract: A method and apparatus for powering a high power load (on the order of 50,000 watts or more) can have an input from any of a plurality of different voltage sources, AC or DC. In one embodiment, the AC sources can have a frequency in the range of 16⅔-60 Hertz, and voltages in the range of 480-38,000 volts. The method and apparatus feature cryocooling inverter electronics, which converts an input signal to a high frequency high voltage signal, to, for example, less than about 180 K. A high frequency transformer receives the high frequency high voltage signal and transforms it into a desired voltage level which can then be filtered and/or demodulated and applied to the load. The transformer is preferably comprised of a superconducting material, and then, the inverter and transformer, at least, are actively cooled as required.

Abstract: A method and apparatus for powering a high power load (on the order of 50,000 watts or more) can have an input from any of a plurality of different voltage sources, AC or DC. In one embodiment, the AC sources can have a frequency in the range of 162/3-60 Hertz, and voltages in the range of 480-38,000 volts. The method and apparatus feature cryocooling inverter electronics, which converts an input signal to a high frequency high voltage signal, to, for example, less than about 180K. A high frequency transformer receives the high frequency high voltage signal and transforms it into a desired voltage level which can then be filtered and/or demodulated and applied to the load. The transformer is preferably comprised of a superconducting material, and then, the inverter and transformer, at least, are actively cooled as required. In a particular embodiment, the circuitry replaces the heavy transformer construction used in driving induction motors in an electric traction engine from an overhead line or a third rail.

Abstract: A method and converter topology for ensuring charge and discharge of electric current to a coil so as to allow simultaneous and independent charge and discharge thereof, particularly suitable for a superconducting coil and showing an increase in power transfer by a factor of up to two as compared with prior art converters.

Abstract: A multi-phase DC chopper circuit having a different number of phases on each side of the current source. The ciruit utilizes fewer chopper phases and produces more discrete DC voltage steps.

Abstract: A superconducting magnetic energy storage system for applying power to a load includes a superconducting magnet, the inductor of which is supplied with current via a source which may be preset to a desired value of current, and wherein a feedback loop responsive to a sensed current adjusts the source to provide the desired current. Energy from the superconducting magnet is transferred via a series of pulses of current from the magnet to a first capacitor for charging the capacitor to a desired voltage greater than the voltage at the superconducting magnet. A further transfer of energy, via a series of pulses of current, results in a charging of a second capacitor to a voltage lower than the voltage of the first capacitor. The second capacitor feeds the load.

Abstract: A superconducting voltage stabilizer is set forth which utilizes a superconducting coil for storing and releasing electrical energy. A first semiconductor switch is disposed to conduct current from the superconducting coil therethrough when the superconducting coil is to be charged or is to store energy and to inhibit current flow therethrough when the superconducting coil is to release energy. A crowbar circuit including a second semiconductor switch and a dump load are also employed. A third semiconductor switch is connected in parallel with the dump load and is disposed in series between the superconducting coil and the crowbar circuit. Quench detection and control circuits are employed for detecting a quench condition of the superconducting coil.

Abstract: A cryogenically cooled circuit, operating at temperatures at which inductors windings of the circuit exhibit superconducting characteristics, provides unique advantages in high performance, preferably high power circuits. Portions of the circuit (or the entire circuit), as opposed to, for example only the superconducting elements (i.e., inductor winding), are refrigerated to cryogenic temperatures. Advantages in the characteristics of not only the superconducting based components but also the diodes, and gating elements such as MOSFET's, yield a uniquely advantageous circuit enabling the operation of, for example, a switching power supplies, frequency converters, and motor speed controllers with increased performance and efficiency. Size, component count, and stability are benefits attained by cryogenically cooling the entire circuit configuration.

Abstract: A superconducting magnet coil, an insulating layer, and a superconducting magnet which do not generate quenching under cooled and operational conditions are provided by using a fixing resin capable of suppressing microcrack generation in a resin layer which causes quenching.A superconducting magnet coil manufactured by winding a superconducting wire and fixing the wire with resin and a method for manufacturing thereof, wherein said resin is a low cooling restricted thermal stress and high toughness fixing resin having a release rate of elastic energy G.sub.IC at 4.2 K. of at least 250 J.multidot.m.sup.-2, and/or a stress intensity factor K.sub.IC of at least 1.5 MPa.multidot..sqroot.m, and/or a stress safety factor at 4.2 K. of at least 3, and an allowable defect size at least of 0.3 mm.The superconducting magnet coil manufactured in accordance with the present invention does not cause quenching because microcracks are not generated in said resin when the coil is cooled to the liquid helium temperature, i.e.

Abstract: A method and apparatus for charging superconducting magnet coils using the Seebeck effect of thermoelectric materials. Superconducting magnet coils are wound from a superconducting material, such as niobium-titanium, and placed in a cryogenic dewar to cool the coil below the critical temperature at which the coil becomes superconducting. The coil can be charged by providing a suitable thermocouple junction outside the dewar and a reference thermocouple junction inside the dewar and connecting the junctions to the coil in a manner providing charging current flow to the coil in accordance with the Seebeck effect. This method is particularly desirable for use with lightweight magnet systems for use in such applications as magnetic levitation systems for trains, space applications, etc. where the present heavy switching power supplies are undesirable.

Abstract: An energy storage device comprising an array of electrical coils formed from relatively high temperature superconducting material, the coils being arranged around a common axis and carrying working currents in the same sense.

Abstract: An inductive superconducting current storage (2), characterized in that it comprises an inner coil (4) wound from superconducting material and an outer coil (6) wound from superconducting material and disposed around the inner coil (4) in spaced manner therefrom, said inner coil (4) and said outer coil (6) in operation having current flowing therethrough in opposite directions so that the same magnetic flux as in the inner space (14) of the inner coil (4), but of opposite direction, is present in the annular space (12) between inner coil (4) and outer coil (6).

Abstract: An apparatus for producing, storing, and delivering direct current electrical energy to a load which contains a fuel cell, a superconducting magnetic energy storage device, a switch electrically connected between the fuel cell and the superconducting magnetic storage device, and a converter for modifying at least one of the electrical characteristics of the direct current electrical energy.

Abstract: A current limiting method and apparatus for preventing fault overload in a utility power transmission system employs a high power, superconducting coil based pulse transformer for saturating the core of the utility power transformer thereby limiting its current carrying capacity. The utility transformer core is biased to a disadvantageous portion of its B-H curve. A fault condition is detected and as a result the superconducting coil is quenched thereby sending a high energy pulse of current into the utility transformer magnetic core. The core, while heating, does not exceed its capability to maintain a stable thermal condition while at the same time limiting the current being transformed from its input to output lines, until a transformer circuit breaker activates.

Abstract: The present invention relates to a superconductive coil assembly which may be used particularly for a current limiter, the coil assembly comprising a plurality of coaxial cylindrical coils electrically connected in series, each coil comprising two windings of superconductive material electrically connected in parallel, arranged coaxially and wound in opposite directions, wherein in each coil, the windings are separated by a material which has a surface resistance in the radial direction lying in the range 10.sup.-5 .OMEGA..m.sup.2 to 10.sup.-2 .OMEGA..m.sup.2 at the temperature of the cryostat, and in which the strands which constitute the superconductive wires may themselves be covered with a layer of the same material.

Abstract: A variable impedance device comprises a coil (10) and an associated magnetic circuit (16) having a gap receiving a plate (20) of superconducting material which acts as a shield or barrier so that, while the plate (20) is in its superconducting state, magnetic flux is caused to traverse the gap via pathways substantially greater in length than the width of the gap. If a large current is passed through the coil (10), the plate (20) becomes resistive thereby presenting a substantially increased impedance to the current. The device may be used in current limiting applications, or other applications where a variable impedance is required.

Abstract: Electrical energy is transferred or switched by selectively holding off the coupling of a magnetic field to a secondary inductive element (a coil) through a path which contains a high temperature superconductive element (HTS) which is capable of holding off the field when in its superconductive state notwithstanding that it is a high energy magnetic field. The HTS operates to hold off the magnetic field in accordance with the flux exclusion effect. When the HTS element is driven normal by heating with a laser pulse, the flux passes through the element and couples the field to the secondary, which may be connected to a load. A primary coil of superconducting material around the secondary coil can provide superconducting magnetic energy storage. The primary field is held off by HTS elements in the flux path to opposite ends of the secondary coil. These elements may be driven normal by laser pulses to transfer the stored magnetic energy to a load.

Abstract: An inductor uses high temperature superconductors in order to obtain high Q for high frequency operation. The superconductors are applied as thin films to substrates. In some embodiments, superconductor thin films are applied to opposite sides of the same substrate. Superconductive thin films are applied outside the magnetic field establishing superconductive thin films in order to shield against leakage of the magnetic field beyond the inductor. The inductor is connected to a capacitor to realize a resonant circuit used in a power conversion system.

Abstract: The invention relates to superconductor current-limiting apparatus of the type having a magnetic core around which firstly a superconductor component is disposed, followed by an electric coil made of non-superconducting material, the apparatus being designed to be inserted in a line to be protected (L), the assembly constituted by the magnetic core (6A, 6B), the superconductor component (3A, 3B) and the electric coil (2A, 2B) forming a current-limiting unit which is connected in the line to be protected in series with a circuit-breaker.

Abstract: An electrical switch structure which employs superconductive material. A magnetizable core is encompassed by a body of superconductive material. The body of superconductive material has a superconductive state and a normal resistive state and can be placed in either state. The magnetizable core is also encompassed by at least one electrically conductive winding through which electrical current flows to create a magnetic flux within the magnetizable core. When the body of superconductive material is in its superconductive state current is induced therein by the magnetic flux in the magnetizable core. Current flow in the body of superconductive creates a magnetic flux in the magnetizable core which cancels the magnetic flux which is created by current flow in the electrically conductive winding.

Abstract: A superconductive voltage stabilizer employs an improved current switch. The improved current switch controls the release of current stored in an energy storage device or superconducting inductive energy storage coil for selective delivery of the current to a load or an electric utility system. A transformer employed in the current switch provides isolation of the energy storage components from the load, thereby making a local ground possible. The amount of energy which can be recovered from the energy storage device is also increased.

Abstract: A superconducting coil is disclosed. A plurality of coils made of oxide superconducting materials are formed on the respective surfaces of substrates, and the adjacent coils mounted on the substrates are connected by conductors to form one coil. Since the coil consists mainly of oxide superconductor, liquid nitrogen can be used to cool at a temperature less than Tc the coil which is energized in order to generate a magnetic field. Therefore it costs less to generate a magnetic field by the coil than by the conventional coils made of metallic superconductors. In addition, the coil is mechanically strong.

Abstract: A superconducting energy stabilizer having multiple load connections employs DC-DC conversion. A discharging DC-DC converter removes stored energy from a superconducting inductive energy storage device or superconducting magnet and delivers the energy to an energy storage cell for use by a load or a utility or industrial electrical distribution system. Regenerated energy can also be retrieved from regenerative type devices and stored in the superconducting magnet for later use. A charging DC-DC converter provides this function. The charging DC-DC converter and the discharging DC-DC converter as well as an off-the-line power supply which provides energy for storage in the superconducting magnet can operate simultaneously under the control of a control system.

Abstract: A device for inductive current limiting of an alternating current consisting of an induction coil (2), which includes at least one winding and through which current flows, a body (3) made of a ceramic high-temperature superconductor arranged concentrically to the latter and having a centrosymmetrical form which is hollow in the interior, and having located in the interior of said body (3) a concentrically arranged core (4) made of a soft magnetic material of high permeability. In normal operation (rated current), the superconductivity of the body (3) is effective and impedance of the induction coil (2) is very low. With overcurrent (mains short-circuit) the superconductivity disappears and the impedance of the induction coil (2) reaches its maximum, current-limiting value.

Abstract: Thin-film transformer, for example suitable for use in a thin-film magnetic head, comprising a magnetic yoke composed of two magnetically permeable thin layers 3 and 5 and a primary turn constituted by an electrically conducting thin layer 13 and a secondary turn constituted by an electrically conducting thin layer 15. A thin layer 21 of a superconducting material is provided between the layer 3 and the said turns, or the turns are closely fitted together and made of a superconducting material themselves.

Abstract: A system, based on superconducting wires and elements, is used to rapidly generate magnetic field intensities at designated points. The apparatus consists of primary and secondary magnet windings, especially arranged so as to produce rapidly increasing magnetic fields. The primary magnet, located at a distance from the operating area, is charged prior to operation, thus producing a low magnetic field at the said area. Energy transfer to the secondary winding is initiated by induction from the primary winding, thus causing transfer to current to produce a high magnetic field in the said area. This system has many applications, including uses as reconnection-guns and electromagnetic launchers.

Abstract: A process for supplying a current consumer with current from an accumulator for electrical energy, in which electrical energy pulses of very short duration each are supplied to the current consumer from a superconducting accumulator (2) made with superconductors (8) of very small diameter or very small layer thickness. The superconductors (8) are preferably high-temperature superconductors.

Abstract: A disk type magnetohydrodynamic (MHD) generator/channel and a hybrid pulse power transformer (HPPT) with a superconductive primary and a normal secondary for producing high power and high current pulses is disclosed. The HPPT surrounds the MHD channel through which hot gas is supplied. The channel upstream from the HPPT is formed into a flat circular configuration with narrow portion directed perpendicular to the channel passing through the HPPT. A MHD disk generator is positioned on the opposite side of the channel directly opposed from the HPPT. The output from the MHD is connected to the primary of the HPPT. Prior to generating power, the superconducting primary winding of the HPPT is charged to a low current. The primary is then connected to the MHD generator/channel for conditioning. When the channel is fired causing gases to flow through the channel causing the magnet current to increase producing a higher primary field and hence more power generation.

Abstract: The present invention identifies several configurations of conducting elements capable of storing extremely high magnetic fields for the purpose of energy storage or for other uses, wherein forces experienced by the conducting elements and the magnetic field pollution produced at locations away from the configuration are both significantly reduced over those which are present as a result of the generation of such high fields by currently proposed techniques. It is anticipated that the use of superconducting materials will both permit the attainment of such high fields and further permit such fields to be generated with vastly improved efficiency.

Abstract: A superconducting current limiting apparatus includes a first container, a superconducting current limiting element accommodated in the first container, a refrigerant filling the first container for cooling the superconducting current limiting element accommodated in the first container, a second container for accommodating the first container in such a manner that the first container is heat insulated, and a conductor for connecting the superconducting current limiting element to an external power supply system. Such a superconducting current limiting apparatus can be used to limit a short-circuit current. It can be incorporated in a short circuit controlling superconducting system.

Abstract: A superconductive ring or coil is irradiated with a light ray so that its superconducting state is destroyed for a short period of time. Under the destruction of the superconducting state, removal of energy from the superconductive ring or coil or storage of energy therein is stably controlled.

Abstract: A superconductive voltage stabilizer comprises an AC/DC converter, a voltage regulator, an energy storage cell and a superconducting energy storage coil. Alternating current is converted to direct current and stored in a superconducting coil. The stored direct current is selectively delivered to an energy storage cell to satisfy the energy requirements of a load. A voltage regulator senses the energy drawn from the energy storage cell and when appropriate releases stored energy from the superconducting coil to maintain a constant supply of energy to the load.

Abstract: Disclosed is an apparatus for storing electrical energy in a superconducting coil. The secondary phenomenon of magnetic induction which limits the size of existing superconducting energy storage coils is overcome by utilizing two superconductor material coils coupled by mutual induction through a high permeability magnetic material. This eliminates induction in the superconductor material thus eliminating the difficulty of the destruction of superconducting capability because of secondary induction. This construction permits high current storage capability in a small volume.

Abstract: A CMOS circuit including a variable conductor means interposed between a power supply and the CMOS circuit. The CMOS circuit comprises a P channel MOS FET and an N channel MOS FET laterally formed on the surface of a semiconductor substrate, inherently producing a parasitic thyristor which can be latched-up with destructive consequences under certain circumstances. The variable conductor means, interposed between the power supply and CMOS circuit, preferably includes a superconductor arranged to sharply switch to a normal conductor mode when the current level exceeds a critical current level, established to be less than the latch-up holding current of the parasitic thyristor, thereby to prevent latch-up.

Abstract: A superconducting switching device having no moving components for reversing current flow through a load. This load typically is a superconducting magnet and, in this application, the present invention also selectively serves as a persistent switch. The invention includes a pair of switching units connected between the load (magnet) and a current source. These switching units each have a pair of superconductor members and a mechanism for selectively producing in the switching units either a substantial electrical resistance or no resistance. Through the use of a control logic, the level of resistance of the switching units can be changed to effect the direction of current flow. In the case of the superconductor magnet, both switch units can be simultaneously made to have substantially zero resistance, and their interconnection forms the persistent switch for the superconducting magnet.

Abstract: A pulsed transformer utilizing the transition of the primary winding from a superconducting state to a normal state to increase the efficiency of energy transfer to the secondary winding thereof and hence to a load across the secondary winding. The primary winding is constructed as a composite which has minimal resistance when in a superconductive state and significantly higher resistance when in a normal or critical state.

Abstract: A circuit is provided comprising a plurality of series connected superconductive coils. Each of a plurality of series connected shunt resistors is connected in parallel with at least one corresponding series connected superconductive coil. A superconductive switch, which includes a length of superconductive wire, is connected in parallel with the series connected superconductive coils. The switch further includes a first and second heater means which are thermally coupled to the superconductive wire. The first heater means is connectable to an external power supply. The second heater means has a plurality of different sections with each of the shunt resistors connected in parallel to one of the sections so that a quench in any of the superconductive coils causes a section of the second heater means to warm and drive the superconductive switch normal.

Abstract: A thyristor bridge interposes an ac source and a load. A series connected DC source and superconducting coil within the bridge biases the thyristors thereof so as to permit bidirectional ac current flow therethrough under normal operating conditions. Upon a fault condition a control circuit triggers the thyristors so as to reduce ac current flow therethrough to zero in less than two cycles and to open the bridge thereafter. Upon a temporary overload condition the control circuit triggers the thyristors so as to limit ac current flow therethrough to an acceptable level.

Abstract: The electric machine comprises a multiphase armature winding 6, a superconducting field winding 4, and a multiphase compensating winding 3 constructed in the form of sections 10. Each phase of the winding 3 is connected in series to one of the phases of the armature winding 6 through a sliding contact. The sections 10 comprise conductors of all the phases, and each phase of the winding 3 is so connected to a separate rectifier 14, 15, 16 that a unidirectional current flows therethrough.

Abstract: A Josephson current regulator circuit is described for regulating the gate current to a Josephson load device. The regulator circuit is located between the source of the gate current and the Josephson load, and is comprised of Josephson devices having a critical current less than the critical current of the Josephson load device. Each of the Josephson regulator devices has at least two states dependent upon the magnitude of the gate current. A resistance is associated with each of the Josephson regulator devices so that, when the state of the Josephson regulator device is changed, resistance is either introduced or removed from the circuit connecting the source and the Josephson load. This adjusts the magnitude of the gate current and maintains within a specified range the ratio of the gate current to the critical current of the Josephson load device.

Abstract: A current control device which may act as a current limiter and/or a VAR generator through the use of a superconducting inductor is taught. In one of the embodiments of the present invention, a full wave bridge rectifier network is serially inserted in one leg of a high voltage transmission system. The output of the full wave bridge network has connected between it a superconducting coil in series with a bias supply. The biasing supply circulates current in the inductor. Should the line current exceed the value of the current circulating in the inductor, the inductor impedes the increase of current giving sufficient time for current interruption devices, should they be utilized, to operate. Additionally, the biasing supply may act as a VAR generator by controlling the current in the superconductor or in the power supply feeding it.

Abstract: Static VAR control means employing an asymmetrically controlled Graetz bridge and a superconducting direct current coil having low losses and low cost characteristics.