Abstract: A control circuit for outputting a pulsed signal includes a switch circuit having a first terminal, a second terminal, a third terminal, a fourth terminal, a first control terminal, and a second control terminal, where the first terminal and the second terminal input the DC signal, the third terminal and the fourth terminal output the pulsed signal, the third terminal and the fourth terminal output the pulsed signal in response to the first control terminal and the second control terminal receiving the first signal, and stop outputting the pulsed signal in response to the first control terminal and the second control terminal receiving the second signal; and an energy storage circuit having two terminals connected to the first terminal and the second terminal of the switch circuit to store residual electric energy of the switch circuit when the switch circuit does not output the pulsed signal.

Abstract: There is described a magnet assembly comprising a superconducting coil, a cryogenic system, a DC voltage source, an SMPS, current leads, and a controller. The cryogenic system comprises a cryostat and is configured to maintain the superconducting coil at an operating temperature below the critical temperature of the superconductor. The DC voltage is source located outside the cryostat. The SMPS is located inside the cryostat and configured to supply power from the DC voltage source to the superconducting coil. The SMPS comprises a voltage step-down transformer having a primary and a secondary winding. The current leads connect the DC voltage source to the SMPS. The controller is configured to cause the SMPS to supply a first amount of power to the magnet in order to ramp up the magnet to operating current, and a second amount of power to the magnet during steady state operation of the magnet, wherein the first amount of power is greater than the second amount of power.

Abstract: A method for heating a wind turbine facility includes: charging a DC link of an electrical converter connected with a wind turbine of the wind turbine facility; heating air inside the wind turbine facility with heat generated by a voltage limiting unit interconnected with the DC link, which includes a resistor adapted for dissipating electrical energy into heat for reducing a voltage in the DC link, when the voltage is above a threshold voltage; wherein the voltage limiting unit is controlled, such that the voltage limiting unit generates heat according to settings defined in a controller of the voltage limiting unit. The heating settings are changed based upon commands from a user interface. Furthermore, the DC link is charged by a grid side converter of the wind turbine facility with power from an electrical grid.

Abstract: A bypass switch is connected in parallel to an inductor of a power supply circuit for a control circuit connected to an auxiliary coil, and an output voltage detection circuit connected to the auxiliary coil detects a load state of the secondary side of a transformer. In a control circuit, an error amplifier and a capacitor generate a voltage (an error signal) corresponding to the load state from the difference between a voltage sampled from a signal detected by the output voltage detection circuit by a sample and hold circuit and a reference voltage. A comparator switches the switch OFF when the load is heavy and switches the switch ON when the load is light. This makes it possible to ignore the effect of the inductor when the load is light, and therefore only the heavy load state needs to be considered to keep the output voltage of the secondary side adjusted appropriately.

Abstract: An electricity distribution system, arranged to provide low voltage to end users (for instance, transport means) and located at end user locations includes a first medium voltage line for providing medium voltage and several end user electricity providers associated with respective several end user locations. Each end user electricity provider is couplable to an end user located at the respective end user location, and is arranged to provide low voltage to the end user. The first medium voltage line is provided with a number of branches and the end user electricity providers are each couplable to a respective branch of the medium voltage line via a respective second medium voltage line to receive medium voltage, and are arranged to convert the medium voltage to the low voltage to be provided to an end user.

Abstract: A DC superconducting coaxial transmission system provides electrical transmission of 5,000 megawatts of energy while simultaneously delivering liquid hydrogen. The transmission system includes a coaxial transmission segment including an inner superconductor, an outer superconductor disposed in surrounding relation to the inner conductor, and a dielectric insulator disposed between the inner superconductor and the outer superconductor. Liquid hydrogen surrounds the superconductors. Three phase transformers and poly phase rectifier/inverters provide a DC voltage source to the superconductors from the electrical grid. In one embodiment, a switching circuit connected between the voltage source and the superconductor injects a cancellation current component into the direct current flow.

Abstract: A power circuit includes a memory power circuit and a central processing unit (CPU) power circuit. The memory power circuit includes a first operational amplifier and a first switch. The CPU power circuit includes a second operational amplifier and a second switch. The memory power circuit supplies power to a memory slot. The CPU power circuit supplies power to a CPU.

Abstract: A magnetic powder core comprises a molded article of a mixture of a glassy alloy powder and an insulating material. The glassy alloy comprises Fe and at least one element selected from Al, P, C, Si, and B, and has a texture primarily composed of an amorphous phase. The glassy alloy exhibits a temperature difference &Dgr;Tx, which is represented by the equation &Dgr;Tx=Tx−Tg, of at least 20 K in a supercooled liquid, wherein Tx indicates the crystallization temperature and Tg indicates the glass transition temperature. The magnetic core precursor is produced mixing the glassy alloy powder with the insulating material, compacting the mixture to form a magnetic core precursor, and annealing the magnetic core precursor at a temperature in the range between (Tg−170) K and Tg K to relieve the internal stress of the magnetic core precursor. The glassy alloy exhibits low coercive force and low core loss.

Abstract: Energy distribution and conversion system suitable for high-rise structures, large building complexes, factories, ships, airplanes, city blocks, etc., based on: High-Temperature Superconductors (HTS) and Cryogenic Power and Energy Conversion (CPEC) using Low-Temperature Operated Semiconductor Devices (LOTOS). Energy from an AC source is converted to DC by LOTOS, distributed as DC, and reconverted at low temperatures to AC at levels and fequencies to satisfy individual end-users of energy. The DC energy is distributed via a plurality of super-conductive leads that are submerged in cryogenic liquid. Substantial savings in energy, cost, size, weight are produced. Additionally, load shedding, power quality, and fire protection are provided. The new system supports air conditioning/cooling systems. Expensive floor space is saved; electrical energy savings of 5-10% are achieved.

Abstract: A transfer of power between an energy storage device and a load is controlled by obtaining a DC voltage from the energy storage device, and controlling a phase angle of AC power delivered to the load to keep the DC voltage substantially constant. The phase angle of the AC power is controlled by controlling a current component of the AC power.

Abstract: A magnetooptical recording medium includes a first magnetic layer, a second magnetic layer whose Curie temperature is lower than that of the first magnetic laye, and a third magnetic layer, comprising a vertically-magnetizing film, whose Curie temperature is higher than that of the second magnetic layer. The first magnetic layer, the second magnetic layer and the third magnetic layer are in a state of exchange coupling with each other at a portion of a vertically-magnetizing film. A domain walls formed in the first magnetic layer moves when the temperature of the medium has been raised to at least the Curie temperature of the second magnetic layer.

Abstract: An electronic circuit that comprises a MOSFET device includes source, drain and gate terminals and operates at cryogenic temperatures. The circuit includes a snubber that is connected between the source and drain terminals of the MOSFET and that has capacitance but substantially no resistance. A control element, which is coupled to at least the gate terminal of the MOSFET device, turns the device "on" (i.e., it effects conduction in the MOSFET) by selectively applying a voltage to the gate terminal that is positive with respect to the source terminal and with respect to ground. The circuit further includes a resistive load, e.g., a resistor, that is coupled in series between the control element and the gate terminal. The control element selectively applies negative-going voltage to the gate terminal, e.g., when the MOSFET is not on.

Abstract: A control circuit generates signals for controlling the sequence in which selected input signals are carried across the terminals of a polyphase switching conversion circuit. The control circuit includes switching elements galvanically isolated from the selected input signals with the control signals electrically isolated from the switching devices. The control circuit for the conversion circuit is, in essence, electrically isolated from the conversion circuit. The control circuit is configured to have a topology analogous to that of the switching converter and includes conventional switching diodes as well as a light generating device optically coupled to a light sensor which, in response to detection of light from the optically coupled light generating device, provides a control signal to a corresponding switching device. The control circuit also includes a source of regulated and electrically isolated power to operate drive circuitry for the switching devices.

Abstract: A superconductive system for receiving electromagnetic energy from an outside source, storing electromagnetic energy in two interacting forms of DC and AC electric current, and delivering electromagnetic energy to an outside load wherein the electromagnetic energy is charged into and discharged from the superconductive storing system exclusively via inductive coupling links. The electromagnetic energy is stored in the form of DC current in high-capacity superconductive coils with each coil connected into a superconductive permanent close loop circuit. The energy is then used to support electromagnetic oscillation in a superconductive oscillating circuit wherein it is stored in low capacity superconductive coils in the form of AC current. The superconducting oscillating circuit is then used to provide power to an outside source.

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: An energy management system for a hybrid internal combustion and electric vehicle provides a highly energy-efficient and yet highly agile hybrid vehicle. The vehicle includes an internal combustion engine, an electric motor/generator and at least one electric storage battery for storing and dispensing energy, all operating in conjunction with an energy storage system including a sensing and control unit and a superconducting magnetic energy storage device. The sensing and control unit is connected to the motor/generator, the battery and the storage device, and has as an input at least one sensor signal representative of a preselected sensed vehicle condition.

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 DC to DC converter has a transformer with a highly coupled primary and secondary, a first switch connected in series between a current source and the primary, a second switch connected across the current source in parallel with the first switch and the primary, a rectifier connected to rectify the output of the secondary, an energy storage device such as a capacitor connected to receive the output from the rectifier, and a load connected to receive output voltage across the capacitor. The current source which provides the substantially constant current can be a superconducting storage magnet. The first and second switches are controlled to alternately open and close to provide current through the primary of the transformer to recharge the energy storage device. When voltage across the energy storage capacitor reaches a minimum level, the one of the first and second switches which was closed is opened and the other is closed.

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 cooling system employs a cooling liquid and a cooling gas in a combined thermodynamic cycle to overcome the flow resistance of dense assemblies of heat generating components and to improve heat transfer by inducing turbulence, thereby reducing the effects of thermal hysteresis and boundary layer formation. Sensible heat gain to the cooling liquid and gas and latent heat of vaporization of the cooling liquid also occur in channels through and over the components. The flow of cooling gas propels the cooling liquid through the channels. The cooling system is advantageous for cooling electronic components such as integrated circuits which exhibit relatively high degree of energy and physical density, in supercomputers. The cooling system may also be advantageously combined with an immersion cooling system for the power supply components in the computer.

Abstract: An electrical power converter including both DC and AC power terminals which are respectively connected to a DC current source and an AC voltage source, the latter comprising the grid of an AC power utility. A capacitor is coupled to the AC terminals along with a load. A control and gating circuit is coupled to the converter for supplying control signals for the thyristors of a converter bridge included in the polyphase converter. When disconnected from the utility grid, a relatively fast acting control loop is coupled to the control and gating circuit and is responsive to the current flowing in the capacitor and an AC reference voltage to accommodate the current source characteristics of the converter for maintaining an output voltage of substantially constant amplitude across the AC terminals.

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: Disclosed is a novel switching device. In its currently preferred embodiment the device comprises a conductive path that comprises a superconductive section, with the remainder of the path being non-superconductive, means for applying a voltage across the path such that a current flows, and means for changing the current in the path from a first value to a second value, where one of the two values is below, and the other is above, a critical current associated with the superconductive section of the path. Depending on the choice of applied voltage and path parameters changing the current from the first to the second state results in switching of the current, either oscillating between two levels of current, or to a steady value. Exemplarily, the current is changed by changing the applied voltage or by changing the resistance of the non-superconductive portion of the conductive path. The device can be used as, for instance, a microwave oscillator or a (binary) photodetector.

Abstract: Superconducting rectifier for the conversion of a relatively low current from an alternating current supply source into a relatively high direct current, essentially consisting of a transformer, at least the secondary coil of which is constructed in semiconducting form, and superconducting switches for the passing of the alternating current induced in the secondary transformer coil through a load, in which the superconducting switches means consist of a commutating part and a blocking part which function independently of each other and are connected in series, and in which the increase in resistance (R) which the commutating part produces upon opening the switching means fulfils the condition ##EQU1## being appreciably lower than the increase in resistance which the blocking part produces upon opening the switches means.

Abstract: A circuit for storing energy delivered from an AC supply comprises a DC capacitor and a reversible chopper between an AC/DC reversible conversion circuit connected to the AC supply and a current supply circuit including a superconductive coil. This capacitor is connected intermittently to the superconductive coil in response to the action of the reversible chopper, so that when connected it delivers energy to the superconductive coil or receives energy therefrom. The reversible chopper circuit controls in accordance with required values the magnitude of transfer of energy between the DC capacitor and the superconductive coil.

Abstract: A rectifying circuit includes a superconductive device and a circuit which controls a magnetic field to be applied to the superconductive device in response to the phase of an A.C. signal applied to the superconductive device, the state of the superconductive device being alternately and repeatedly changed-over between a superconductive state and a nonsuperconductive state by the magnetic field so as to rectify the A.C. signal.

Abstract: Superconducting films and devices are provided which exhibit an AC to DC conversion effect of an RF AC input signal. The films can be microscopically inhomogeneous with granular or columnar microstructures in layered or nonlayered structures, which provide the conversion effect with and without an applied magnetic field. The films also can be multilayer films which provide the conversion effect with a magnetic field applied to the films. The multilayer films are substantially compositionally homogeneous within the layers and the microscopically inhomogeneous films are substantially compositionally homogeneous throughout, but include structural inhomogeneities.

Abstract: A superconducting magnetic energy storage coil connected in parallel between converters of two or more ac power systems provides load leveling and stability improvement to any or all of the ac systems. Control is provided to direct the charging and independently the discharging of the superconducting coil to at least a selected one of the ac power systems.

Abstract: A circuit for transmitting energy to and from coils is improved by connecting a coil to a bridge circuit composed of a diode and a switch such as a gate turn-off thyristor. An opposite polarity switch and diode construction may be used in addition to selectively allow the direction of current flow through the coil to be reversible.

Abstract: A superconduction power storage apparatus includes a superconduction coil for storage and release of electrical energy, and a separately excited thyristor conversion unit having d.c. terminals connected to the said superconduction coil and a.c. terminals connected to an a.c. power source. The conversion unit is arranged so as to convert the electrical energy from a d.c. form to an a.c. form and vice versa between the superconduction coil and the a.c. power source. An on-load voltage regulator is connected between the a.c. side terminals of the thyristor conversion unit and the a.c. power source, and is arranged for adjusting the voltage appearing at the a.c. terminals of the thyristor conversion unit.

Abstract: In an inductor-convertor circuit for transferring electrical energy between a storage coil and a load coil using a storage thyristor bridge, a load thyristor bridge, and a set of commutating capacitors, operation is improved by a method of changing the rate of delivery of energy in a given direction. The change in rate corresponds to a predetermined change in phase angle between the load bridge and the storage bridge and comprises changing the phase of the bridge by two steps, each equal to half the predetermined change and occurring 180.degree. apart. The method assures commutation and minimizes imbalances that lead otherwise to overvoltages.

Abstract: Energy derived from an alternating current power system is stored in a superconducting magnet or inductor. The transfer of the energy is reversible so that the energy stored in the superconducting magnet can be returned to the alternating current power system. Generally, the energy is stored when surplus energy is available, due to low demand. The energy stored in the superconducting magnet may be returned to the power system when demand is high. High efficiency in the storage and return of the energy is achieved. A reversible converter is provided between the alternating current system and the superconducting magnet so that the magnet is supplied with direct current when energy is being stored. The converter may be adjusted so as to convert directcurrent into alternating current when it is desired to return the stored energy to the power system.

Abstract: A power supply capable of transferring power at high current and voltage levels to a load which may be highly inductive. The power supply includes an inverter for receiving DC power and inverting it to an AC intermediate signal. The intermediate signal is rectified by a converter to provide a DC output voltage to a load. Commutation of the controlled rectifying devices within the inverter and converter are provided by capacitors connected across the output terminals of the inverter. The DC output voltage provided to the load is controlled by the frequency of the firing signals provided to the controlled rectifying devices within the inverter. A large energy storage inductor, which may be superconductive, is connected to the inverter and may be utilized to provided the pulses of power required by the load. A converter connected to an AC power system is provided to supply external power and to recharge the current flowing in the energy storage inductor.

Abstract: Apparatus for electrically chopping a direct current signal by controlling the superconductivity state of resistance elements contained within a cryostat. The resistance elements are in a bridge arrangement and the control is provided by laser diodes also contained within the cryostat.

Abstract: Type II superconductive materials having greatly diminished vortex pinning as a result of maintaining the ratio of the average scale of structural disorder of the materials to vortex core size to not greater than about 120% of the minimum such ratio, superconductive devices utilizing such materials, and a method for producing such materials.

Abstract: An inductor device having a superconducting coil winding capable of maintaining a relatively large current flowing therethrough, and a normal conducting shield winding surrounding the superconducting coil. The superconducting coil and the shield are electrically connected in parallel with the shield functioning to maintain the current and the magnetic field in the superconducting coil substantially constant. The superconducting inductor device can be used to store energy and to return the stored energy to an energy consuming load over a relatively short period without incurring large losses in the superconducting material. This result is obtained by making the self inductance of the shield substantially equal to the mutual inductance between the shield and the superconducting coil, or by inserting a controlled compensating voltage source in series with the shield, so that pulse currents are conducted by the shield.