Abstract: Disclosed is provided a hybrid-type superconducting fault current limiter for rapidly limiting a fault current, the fault current limiter having a first circuit and a second circuit which are connected in parallel with each other, wherein the first circuit includes a superconductor and a circuit breaker which are connected in series with each other, and wherein the second circuit includes a driver having a driving coil and an electromagnetic repeller, a short contact connected in parallel with the driver, and a current limiting unit connected in series with a third circuit including the driver and the short contact. The hybrid-type superconducting fault current limiter comprises a power semiconductor element switch connected in series with the first circuit, the power semiconductor element switch normally maintaining an ON state and being activated and changed into an OFF state by a fault sensing signal generated according to an inflow of the fault current.

Abstract: A resistive superconducting fault current limiter comprises: a superconducting limiter element which is in a superconductive state in the event of a normal current occurrence, and which is in a normal conductive state having a predetermined resistance when a fault current larger than a predetermined threshold current value flows; a superconducting serial coil serially connected to the superconducting limiter element so as to face each other so that a current loss can be minimized accordingly as currents flow in opposite directions thus to cancel magnetic fields, and having a threshold current value greater than the threshold current value of the superconducting limiter element by a predetermined ratio; and a normal conductor parallel coil connected to the superconducting limiter element in parallel and having a predetermined resistance smaller than the resistance of the superconducting limiter element when a fault current occurs, for preventing the superconducting limiter element from being overheated by divi

Abstract: An electric power circuit protecting apparatus using a superconductor in an electric power system needing re-closing within a predetermined time from fault current blocking, comprising a main circuit breaker; a first superconductor element connected in series to the main circuit breaker; a first auxiliary switch to switch a circuit between the first superconductor element and the main circuit breaker; a second superconductor element connected in parallel to the first superconductor element and the first auxiliary switch; a second auxiliary switch to switch a circuit between the second superconductor element and the main circuit breaker; a first monitoring unit for detecting a voltage across the first superconductor element and for supplying a first switching control signal to the first auxiliary switch to be switched to the circuit open position, and a second switching control signal to the second auxiliary switch to be switched to the circuit close position; and a second monitoring unit for detecting a volta

Abstract: Disclosed is a half-wave expulsion type superconducting fault-current limiter having an integral high speed switch module. The fault-current limiter has minimum superconducting elements and a circuit of which is formed in a hybrid type with an integral high speed switch module. The fault-current limiter supplies an electric power supplied from a power feeder to a system without loss thereof according to unique characteristics of the superconducting element when a normal current flows, and restricts an over current through a high speed switching contact point integrally inter-working with a driving coil and an arc changeover switch past a half period in a case that the over-current is generated by accidents such that electric power appliances, including circuit breakers in an electric power system, can be normally operated.

Abstract: Disclosed is provided a hybrid-type superconducting fault current limiter for rapidly limiting a fault current, the fault current limiter having a first circuit and a second circuit which are connected in parallel with each other, wherein the first circuit includes a superconductor and a circuit breaker which are connected in series with each other, and wherein the second circuit includes a driver having a driving coil and an electromagnetic repeller, a short contact connected in parallel with the driver, and a current limiting unit connected in series with a third circuit including the driver and the short contact. The hybrid-type superconducting fault current limiter comprises a power semiconductor element switch connected in series with the first circuit, the power semiconductor element switch normally maintaining an ON state and being activated and changed into an OFF state by a fault sensing signal generated according to an inflow of the fault current.

Abstract: Disclosed is a half-wave expulsion type superconducting fault-current limiter having an integral high speed switch module. The fault-current limiter has minimum superconducting elements and a circuit of which is formed in a hybrid type with an integral high speed switch module. The fault-current limiter supplies an electric power supplied from a power feeder to a system without loss thereof according to unique characteristics of the superconducting element when a normal current flows, and restricts an over current through a high speed switching contact point integrally inter-working with a driving coil and an arc changeover switch past a half period in a case that the over-current is generated by accidents such as thunder-stroke, earth fault and short circuit, such that electric power appliances such as circuit breakers in an electric power system can be normally operated.

Abstract: Disclosed is a resistive superconducting fault current limiter capable of enhancing a current of a superconducting device thereof, capable of preventing heat generated at a linear coil, capable of removing a magnetic field generated through the linear coil when a normal current is applied to a circuit of a power system, and capable of using not only a BISCCO based superconducting device but also a YBCO based superconducting device with using a magnet generating device separated from the circuit of the power system so that a current of the power system can not flow to the linear coil of the resistive superconducting fault current limiter when a normal current flows to the power system.

Abstract: The present invention relates to a complex superconducting fault current limiter which adds a current limiting reactor to a superconductor to protect the power line from a fault current, and more particularly, to a complex superconducting fault current limiter using a minimum number of superconducting fault current limiters, while avoiding series and parallel connections of a plurality of superconductors and coils, in order to economically manufacture the fault current limiter in a small size. A superconductor, a high speed switch, and a circuit breaker are connected in series to each other, and a first reactor with a low impedance and a second reactor with a high impedance are connected in parallel to the power line so as to provide a branch circuit for the current to the series circuit. A semiconductor switch is connected in parallel to the second reactor with a high impedance in accordance with the opening high speed switch.

Abstract: An electric power circuit protecting apparatus using a superconductor in an electric power system needing re-closing within a predetermined time from fault current blocking, comprising a main circuit breaker; a first superconductor element connected in series to the main circuit breaker; a first auxiliary switch to switch a circuit between the first superconductor element and the main circuit breaker; a second superconductor element connected in parallel to the first superconductor element and the first auxiliary switch; a second auxiliary switch to switch a circuit between the second superconductor element and the main circuit breaker; a first monitoring unit for detecting a voltage across the first superconductor element and for supplying a first switching control signal to the first auxiliary switch to be switched to the circuit open position, and a second switching control signal to the second auxiliary switch to be switched to the circuit close position; and a second monitoring unit for detecting a volta

Abstract: A resistive superconducting fault current limiter comprises: a superconducting limiter element which is in a superconductive state in the event of a normal current occurrence, and which is in a normal conductive state having a predetermined resistance when a fault current larger than a predetermined threshold current value flows; a superconducting serial coil serially connected to the superconducting limiter element so as to face each other so that a current loss can be minimized accordingly as currents flow in opposite directions thus to cancel magnetic fields, and having a threshold current value greater than the threshold current value of the superconducting limiter element by a predetermined ratio; and a normal conductor parallel coil connected to the superconducting limiter element in parallel and having a predetermined resistance smaller than the resistance of the superconducting limiter element when a fault current occurs, for preventing the superconducting limiter element from being overheated by divi

Abstract: Disclosed is a breaker for providing successive trip mechanism based on PTC current-limiting device, which includes a first switch having first fixed/movable contact points; a second switch having second fixed/movable contact and connected to the first switch in parallel; PTC current-limiting device connected to the first and second switches in parallel or series and allowing a change of current flow direction from the first switch to the second switch at a fault current; a movable arm to which the movable contact points are installed at an interval therebetween and opening/closing the switches by operating the movable contact points; a fixed arm including first and second fixed arm conductors for guiding current flow toward the first fixed contact point in a normal load current mode and guiding current flow toward the second fixed contact point via the PTC current-limiting device in a fault current mode; and a successive trip means for elastically biasing the second switch by operation of the movable arm in

Abstract: Disclosed is a breaker for providing successive trip mechanism based on PTC current-limiting device, which includes a first switch having first fixed/movable contact points; a second switch having second fixed/movable contact and connected to the first switch in parallel; PTC current-limiting device connected to the first and second switches in parallel or series and allowing a change of current flow direction from the first switch to the second switch at a fault current; a movable arm to which the movable contact points are installed at an interval therebetween and opening/closing the switches by operating the movable contact points; a fixed arm including first and second fixed arm conductors for guiding current flow toward the first fixed contact point in a normal load current mode and guiding current flow toward the second fixed contact point via the PTC current-limiting device in a fault current mode; and a successive trip means for elastically biasing the second switch by operation of the movable arm in

Abstract: Disclosed is a PTC (Positive Temperature Coefficient) current limiting device, which limits a current using PTC characteristics. The device includes a PTC element having the PTC characteristics; and upper and lower contact electrodes arranged to face each other with the PTC element being interposed therebetween, wherein, assuming that a distance from an end of the upper contact electrode to an end of the PTC element is a1, a distance from an end of the lower contact electrode to the end of the PTC element is a2, a thickness of the PTC element is b, and L=a1+a2+b, the following equations are satisfied: V/L<10 and V/b<50, where V is a rated voltage of the PTC current limiting device, a unit for a1, a2 and b is mm, and a unit for V is volt. This PTC current limiting device may prevent generation of flashover between electrodes.

Abstract: Disclosed is a PTC (Positive Temperature Coefficient) current limiting device for limiting a current by use of PTC characteristics, which includes a PTC element having the PTC characteristics; a pair of electrode units arranged on both sides to face each other with the PTC element being interposed therebetween; and a molding part prepared around the PTC element and the electrode units to surround at least an interface region between the PTC element and the electrode units, the molding part being made of elastic insulating material. The molding part is made of an elastic insulating material or any insulating materials selected from vacuum, gas and oil. Thus, this device may effectively restrain an arc generated while limiting overcurrent or short circuit current, and also prevent flashover between electrodes.

Abstract: Disclosed is a resistive superconducting fault current limiter capable of enhancing a current of a superconducting device thereof, capable of preventing heat generated at a linear coil, capable of removing a magnetic field generated through the linear coil when a normal current is applied to a circuit of a power system, and capable of using not only a BISCCO based superconducting device but also a YBCO based superconducting device with using a magnet generating device separated from the circuit of the power system so that a current of the power system can not flow to the linear coil of the resistive superconducting fault current limiter when a normal current flows to the power system.