Abstract: Disclosed is a method and apparatus for detecting anomalies in a system log on the basis of self-supervised learning, using a language model. The method comprises performing preprocessing on the system log, generating a normal token sequence having a preset length by concatenating tokenized log lines of the system log, generating an abnormal token sequence using the normal token sequence, calculating an anomaly score for a determination target token sequence using a sentence classification model, and determining the token sequence as an abnormal system log when the calculated anomaly score is greater than a threshold value.

Abstract: The DC interrupting device includes a main current conduction unit including a main interrupting switch, which is a mechanical switch, a reverse current power supply unit connected to an input terminal of the main current conduction unit and configured to generate a predetermined reverse current, and a reverse current conduction unit configured to supply the reverse current to an output terminal of the main current conduction unit. The reverse current power supply unit includes a first reverse current dedicated capacitor charged by a voltage applied to an input terminal of the main current conduction unit, a polarity reversing inductor configured to reverse a polarity of the first reverse current dedicated capacitor, and a reverse current power supply unit switch configured to perform circuit connection such that the polarity reversing inductor reverses the polarity of the first reverse current dedicated capacitor.

Abstract: A high speed switch comprises an interrupter unit connected to a main circuit and including a movable electrode and a driving electrode for opening or closing the main circuit; a driving unit including a repulsion coil for providing a driving force for moving the movable electrode of the interrupter unit, and a repulsion plate disposed opposite to the repulsion coil; a guide rod part connecting the movable electrode of the interrupter unit to the repulsion plate, having a latch groove formed therein, and reciprocating vertically according to movements of the repulsion plate; and a state-holding unit for regulating the movement of the guide rod part, wherein the state-holding unit comprises: a latch pin; a latch elastic member; and a latch coil.

Abstract: A high speed switch comprises an interrupter unit connected to a main circuit and including a movable electrode and a driving electrode for opening or closing the main circuit; a driving unit including a repulsion coil for providing a driving force for moving the movable electrode of the interrupter unit, and a repulsion plate disposed opposite to the repulsion coil; a guide rod part connecting the movable electrode of the interrupter unit to the repulsion plate, having a latch groove formed therein, and reciprocating vertically according to movements of the repulsion plate; and a state-holding unit for regulating the movement of the guide rod part, wherein the state-holding unit comprises: a latch; a latch elastic member; and a latch coil.

Abstract: The DC interrupting device includes a main current conduction unit including a main interrupting switch, which is a mechanical switch, a reverse current power supply unit connected to an input terminal of the main current conduction unit and configured to generate a predetermined reverse current, and a reverse current conduction unit configured to supply the reverse current to an output terminal of the main current conduction unit. The reverse current power supply unit includes a first reverse current dedicated capacitor charged by a voltage applied to an input terminal of the main current conduction unit, a polarity reversing inductor configured to reverse a polarity of the first reverse current dedicated capacitor, and a reverse current power supply unit switch configured to perform circuit connection such that the polarity reversing inductor reverses the polarity of the first reverse current dedicated capacitor.

Abstract: Disclosed herein is a current circuit breaker that protects a semiconductor module by using fast switches to block a current. The current circuit breaker includes: a first switch configured to be opened upon a fault current being generated; a second switch connected to the first switch and configured to be opened after a predetermined period of time elapses since the first switch has been opened; a semiconductor module having an end connected to the first switch and another end connected to the second switch; a capacitor having a terminal connected to the second switch and the other terminal connected to the semiconductor module; and a surge arrester connected across the capacitor and configured to change its resistance according to a voltage across the capacitor to block the fault current.

Abstract: An apparatus for detecting a defect of an electric power system according to one embodiment of the present disclosure includes a first state signal output unit for outputting a first state signal corresponding to a magnetic force generated at a periphery of a line, a second state signal output unit for outputting a second state signal based on a magnitude of a line current and an increase ratio thereof, and a determination unit for determining whether the electric power system is defective or not based on the first state signal and the second state signal.

Abstract: Disclosed is a direct current (DC) circuit breaker including a first line in which a first high-speed switch and a power semiconductor switch are connected in series; a second line in which a plurality of second high-speed switches, a plurality of pairs of a first non-linear resistor and a power fuse connected in parallel, and a resistor are connected in series; and a third line including a second non-linear resistor. The first line, the second line, and the third line are connected in parallel.

Abstract: Some embodiments of the present disclosure relate to a direct current circuit breaker capable of shortening a cut-off operation time and reducing a magnitude of a required reverse current. The direct current circuit breaker includes: a main circuit line which is connected between a power supply and a load, the main circuit line includes a main breaker and a first diode connected in parallel; a charging circuit line which is disposed in the rear stage of the main breaker and is connected in parallel to the load, the charging circuit line includes a first capacitor, a reactor and a second diode connected in series; and a switch line including one end connected in parallel to the front stage of the main breaker and the other end connected between the reactor and the second diode, the switch line includes a third diode and a current switch connected in series.

Abstract: Disclosed embodiments relate to a DC circuit breaker and a circuit breaking method thereof which comprises: a measuring portion for measuring a DC current conducted through a first circuit portion; the first circuit portion for conducting and blocking the DC current; and a second circuit portion for conducting and blocking the DC current which is bypassed from the first circuit portion and controlling the open/close operation of the first circuit portion according to a measuring result of the measuring portion, wherein, in the first circuit portion and the second circuit portion, switching elements, which are included in each of them, are connected in a parallel configuration such that a high switching operation during a blocking operation can be improved and the DC current can be blocked in a safer and more efficient manner, and a circuit breaking method of the DC circuit breaker.

Abstract: Disclosed herein is a current circuit breaker that protects a semiconductor module by using fast switches to block a current. The current circuit breaker includes: a first switch configured to be opened upon a fault current being generated; a second switch connected to the first switch and configured to be opened after a predetermined period of time elapses since the first switch has been opened; a semiconductor module having an end connected to the first switch and another end connected to the second switch; a capacitor having a terminal connected to the second switch and the other terminal connected to the semiconductor module; and a surge arrester connected across the capacitor and configured to change its resistance according to a voltage across the capacitor to block the fault current.

Abstract: An apparatus for detecting a defect of an electric power system according to one embodiment of the present disclosure includes a first state signal output unit for outputting a first state signal corresponding to a magnetic force generated at a periphery of a line, a second state signal output unit for outputting a second state signal based on a magnitude of a line current and an increase ratio thereof, and a determination unit for determining whether the electric power system is defective or not based on the first state signal and the second state signal.

Abstract: A fault current detection circuit comprises a primary current transformer that detects a current; a pair of secondary current transformers that convert a current detection signal into secondary conversion signals with a small current; a fault detection circuit section that determines whether or not a fault current occurs by comparing a current value according to a secondary conversion signal with a predetermined reference current value; a surge detection circuit section that determines whether or not a surge current occurs on the electric power circuit; and a trip determination unit that receives a fault detection signal and a surge detection signal, and generates a trip control signal when at least either one of the fault detection signal and the surge detection signal is received.

Abstract: Some embodiments of the present disclosure relate to a direct current circuit breaker capable of shortening a cut-off operation time and reducing a magnitude of a required reverse current. The direct current circuit breaker includes: a main circuit line which is connected between a power supply and a load, the main circuit line includes a main breaker and a first diode connected in parallel; a charging circuit line which is disposed in the rear stage of the main breaker and is connected in parallel to the load, the charging circuit line includes a first capacitor, a reactor and a second diode connected in series; and a switch line including one end connected in parallel to the front stage of the main breaker and the other end connected between the reactor and the second diode, the switch line includes a third diode and a current switch connected in series.

Abstract: A fault current limiter is provided. According to an embodiment of the present disclosure, the fault current limiter includes a switch whose contact point is opened when a fault current occurs; a current limiting element configured to limit the fault current when the fault current occurs; and a diode being serial-connected to the current limiting element, wherein a breakdown voltage of the diode is higher than a voltage drop by an impedance of the switch when a normal current flows.

Abstract: The fast switch includes: a housing; a vacuum interrupter installed in the housing, connected to a main circuit, and configured to open and close the main circuit; a contact spring coupled to a mover of the vacuum interrupter, and configured to provide a contact force; an insulating rod connected to the contact spring; a permanent magnet actuator connected to a lower end of the insulating rod, and configured to provide a switching driving force; a first capacitor configured to provide a discharge current to a coil of the permanent magnet actuator; a driving coil connected to a lower end of the permanent magnet actuator; and a second capacitor configured to provide a discharge current to the driving coil.

Abstract: Disclosed embodiments relate to a DC circuit breaker and a circuit breaking method thereof which comprises: a measuring portion for measuring a DC current conducted through a first circuit portion; the first circuit portion for conducting and blocking the DC current; and a second circuit portion for conducting and blocking the DC current which is bypassed from the first circuit portion and controlling the open/close operation of the first circuit portion according to a measuring result of the measuring portion, wherein, in the first circuit portion and the second circuit portion, switching elements, which are included in each of them, are connected in a parallel configuration such that a high switching operation during a blocking operation can be improved and the DC current can be blocked in a safer and more efficient manner, and a circuit breaking method of the DC circuit breaker.

Abstract: Disclosed is a direct current (DC) circuit breaker including a first line in which a first high-speed switch and a power semiconductor switch are connected in series; a second line in which a plurality of second high-speed switches, a plurality of pairs of a first non-linear resistor and a power fuse connected in parallel, and a resistor are connected in series; and a third line including a second non-linear resistor. The first line, the second line, and the third line are connected in parallel.

Abstract: A fault current detection circuit according to the invention comprises a primary current transformer that detects a current; a pair of secondary current transformers that convert a current detection signal into secondary conversion signals with a small current; a fault detection circuit section that determines whether or not a fault current occurs by comparing a current value according to a secondary conversion signal with a predetermined reference current value; a surge detection circuit section that determines whether or not a surge current occurs on the electric power circuit; and a trip determination unit that receives a fault detection signal and a surge detection signal, and generates a trip control signal when at least either one of the fault detection signal and the surge detection signal is received.

Abstract: The fast switch includes: a housing; a vacuum interrupter installed in the housing, connected to a main circuit, and configured to open and close the main circuit; a contact spring coupled to a mover of the vacuum interrupter, and configured to provide a contact force; an insulating rod connected to the contact spring; a permanent magnet actuator connected to a lower end of the insulating rod, and configured to provide a switching driving force; a first capacitor configured to provide a discharge current to a coil of the permanent magnet actuator; a driving coil connected to a lower end of the permanent magnet actuator; and a second capacitor configured to provide a discharge current to the driving coil.