Abstract: Described herein are fault current limiters including an input terminal for electrically connecting to a power source that provides a load current, and an output terminal for electrically connecting with a load circuit that draws the load current. The fault current limiters include a magnetically saturable core including at least one coil receiving limb disposed intermediate at least two return limbs, wherein the limbs longitudinally extend between at least two yokes, and wherein the at least two yokes and the at least two return limbs define at least a portion of one or more magnetic flux return paths for the at least one coil receiving limb. The fault current limiters further includes at least one AC coil disposed about the at least one coil receiving limb for carrying the load current between the input terminal and the output terminal.

Abstract: A fault current limiter of the type having at least one elongated core biased magnetically towards saturation by means of a surrounding magnetic field, and an AC coil surrounding the core, the fault current limiter including: an elongated core having a variable cross section along the axis of the core in the vicinity of the AC coil, providing increased saturation of the core and enhanced fault current limiting for a lower DC bias.

Abstract: A fault current limiter of the type having at least one elongated core biased magnetically towards saturation by means of a surrounding magnetic field, and an AC coil surrounding the core, the fault current limiter including: an elongated core having a variable cross section along the axis of the core in the vicinity of the AC coil, providing increased saturation of the core and enhanced fault current limiting for a lower DC bias.

Abstract: Described herein are fault current limiters including an input terminal for electrically connecting to a power source that provides a load current, and an output terminal for electrically connecting with a load circuit that draws the load current. The fault current limiters include a magnetically saturable core including at least one coil receiving limb disposed intermediate at least two return limbs, wherein the limbs longitudinally extend between at least two yokes, and wherein the at least two yokes and the at least two return limbs define at least a portion of one or more magnetic flux return paths for the at least one coil receiving limb. The fault current limiters further includes at least one AC coil disposed about the at least one coil receiving limb for carrying the load current between the input terminal and the output terminal.

Abstract: A fault current limiter including: a ferromagnetic circuit formed from a ferromagnetic material and including at least a first limb, and a second limb; a saturation mechanism surrounding a limb for magnetically saturating the ferromagnetic material; a phase coil wound around a second limb; a dielectric fluid surrounding the phase coil; a gaseous atmosphere surrounding the saturation mechanism.

Abstract: In a fault current limiter (FCL) of a saturated core type having at least one coil wound around a high permeability material, a method of suppressing the time derivative of the fault current at the zero current point includes the following step: utilizing an electromagnetic screen or shield around the AC coil to suppress the time derivative current levels during zero current conditions.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: A three-phase fault current limiter FCL has three spaced apart input terminals for electrically connecting to respective terminals of a transformer. Three output terminals electrically connect FCL with a load circuit which draws load current ILOAD. FCL includes two longitudinally spaced apart generally circular High Temperature Superconducting (HTS) DC coils which have central generally cylindrical cavities. FCL also includes a longitudinally extending magnetically saturable core which has six like coextensive parallel and elongate posts. Each post includes a first longitudinal portion and, a second longitudinal portion and a third longitudinal portion extending longitudinally oppositely away from the first portion. Each second portion and third portion is received within one of the central cavities. Three copper-based insulated AC coils are each wound about respective first portions for carrying load current ILOAD between input terminals to respective output terminals.

Abstract: In a fault current limiter (FCL) of a saturated core type having at least one coil wound around a high permeability material, a method of suppressing the time derivative of the fault current at the zero current point includes the following step: utilizing an electromagnetic screen or shield around the AC coil to suppress the time derivative current levels during zero current conditions.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts for collectively define a core for the FCL. A DC coil, for the purposes of saturating a portion of the high permeability posts, surrounds the complete structure outside of an enclosure in the form of a vessel. The vessel contains a dielectric insulation medium. AC coils, for transporting AC current, are wound on insulating formers and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil in the corresponding high permeability core are opposing. There are insulation barriers between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: A fault current limiter including: an input terminal for electrically connecting to a power source that provides a load current; an output terminal for electrically connecting with a load circuit that draws the load current; and at least a first and second core of high magnetic permeability material; at least a first and second interconnected AC coil with a first AC coil formed around a first core and the second AC coil formed around a second core; at least one DC coil for magnetically biasing the cores such that, in response to one or more characteristics of the load current, the AC coil moves from a low impedance state to a high impedance state. A high magnetic permeability non-laminated material formed between the first and second cores. The high magnetic permeability non-laminated material can comprise steel.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts (1) for collectively define a core for the FCL. A DC coil (2), for the purposes of saturating a portion of the high permeability posts (1), surrounds the complete structure outside of an enclosure in the form of a vessel (3). The vessel (3) contains a dielectric insulation medium (4). AC coils (5), for transporting AC current, are wound on insulating formers (6) and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil (5) in the corresponding high permeability core are opposing. There are insulation barriers (7) between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: A method of dampening a transient in a DC biasing coil in a fault current limiter, the method including the step of: interconnecting a transient suppression circuit across the DC biasing coil, the transient suppression circuit being operative when the transient voltage across the DC biasing coil exceeds a predetermined maximum.

Abstract: A fault current limiter designed for connection into a medium voltage, high voltage, or extra-high voltage substation or other high voltage source such as a generator station, the limiter including: a ferromagnetic circuit formed from a ferromagnetic material and including at least a first limb, a second limb and a third limb; a first input phase coil wound around the first limb, a second output phase coil wound around the third limb; a saturation mechanism surrounding a limb for magnetically saturating the ferromagnetic material; a containment vessel providing a substantially uniform, low electrical conductivity medium surrounding the ferromagnetic circuit, the phase coils and the saturation mechanism.

Abstract: A fault current limiter (FCL) includes a series of high permeability posts (1) for collectively define a core for the FCL. A DC coil (2), for the purposes of saturating a portion of the high permeability posts (1), surrounds the complete structure outside of an enclosure in the form of a vessel (3). The vessel (3) contains a dielectric insulation medium (4). AC coils (5), for transporting AC current, are wound on insulating formers (6) and electrically interconnected to each other in a manner such that the senses of the magnetic field produced by each AC coil (5) in the corresponding high permeability core are opposing. There are insulation barriers (7) between phases to improve dielectric withstand properties of the dielectric medium.

Abstract: A fault current limiter including: a ferromagnetic circuit formed from a ferromagnetic material and including at least a first limb, and a second limb; a saturation mechanism surrounding a limb for magnetically saturating the ferromagnetic material; a phase coil wound around a second limb; a dielectric fluid surrounding the phase coil; a gaseous atmosphere surrounding the saturation mechanism.

Abstract: A method is for suppressing induced steady state and transient currents and voltages in the DC circuit and coil of a magnetically saturated core fault current limiter. The method includes the steps of: (a) providing a first current coil connected to a DC power source surrounding the core for magnetically saturating the core; and (b) providing a second resistive current coil surrounding the core and either short circuited or interconnected to the DC power source in parallel to the first current coil and wound around the core in a forward or reverse sense to the first current coil.

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 Winding for high voltage transformer having a predetermined number of spaced winding groups joined to form a single winding transformer, each spaced winding group being solenoid wound from a predetermined number of turns. A method of forming the winding and a transformer including the winding are also disclosed.

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.