Abstract: An asset management method for a substation in accordance with the present invention generates a unique reliability model for each element of the substation by comparing reliability of a reference reliability model for each substation type with a health index of the each element thereof generated based on state data and real-time monitoring data of the each element of the substation and compensating the reference reliability model for the each element of the substation; assessing system reliability index and economic feasibility for each maintenance scenario based on a reference system reliability model for each candidate element subject to maintenance among the elements of the substation; selecting a maintenance scenario as a result of the health index and the unique reliability model for the each element of the substation, the system reliability index, and the economic feasibility and updating the unique reliability model for the each element of the substation by executing maintenance.

Abstract: The present invention relates to a transformer iron core. The present invention comprises: an upper yoke (50); a lower yoke (51) extending in parallel with the upper yoke (50); and an end leg (60) which is installed between the upper yoke (50) and the lower yoke (51), which extends perpendicularly to the longitudinal direction of the upper yoke (50) and the lower yoke (51), and which is coupled to the upper yoke (50) and to the lower yoke (51). The upper yoke (50) and the lower yoke (51) are made by laminating multiple yoke steel plates (50?). The end leg (60) is also made by laminating multiple leg steel plates (60?). The upper yoke (50) and the lower yoke (51) have leg coupling portions (52) on both ends thereof. The end leg (60) has yoke coupling portions (62) coupled to the leg coupling portions (52).

Abstract: An asset management method for power equipment in accordance with the present invention comprises steps of generating integrity of each sub-device of the power equipment by using state data and real-time monitoring data of the each sub-device; compensating a reference reliability model by the each sub-device and generating a unique reliability model by the each sub-device by comparing reliability of the reference reliability model by the each sub-device and the integrity by the each sub-device; calculating reliability of the power equipment by applying a system relationship model between the power equipment and the each sub-device to which specific weight and failure rate are reflected; deriving, and calculating an estimate of, a maintenance scenario by the each sub-device; and updating the reliability model for the power equipment while updating the unique reliability model by the each sub-device by a predetermined priority and according to execution of maintenance.

Abstract: A high-speed solenoid includes a casing, a least two pairs of first permanent magnet and second permanent magnet installed in the casing, and coils corresponding to the pairs of first permanent magnet and second permanent magnet provided in the same number as the number thereof in a bobbin of a mover. In magnetic paths formed by the pairs of first permanent magnet and second permanent magnet and the coils, each magnetic path corresponding to each pair of first permanent magnet and second permanent magnet is separated from each other. Therefore, the multiple magnetic paths are formed to operate the mover. The high-speed solenoid has an advantage in that the mover is operated at a relatively high speed.

Abstract: A method for diagnosing a state of a submodule in initial charging of an MMC converter includes identifying, by an upper level controller, a stopped state of the MMC converter; supplying, by the upper level controller, an alternating current (AC) voltage from an AC side to N submodules in the MMC converter when the MMC converter is in the stopped state; charging a capacitor in the submodule with the supplied AC voltage to store an initial charging voltage in the capacitor; determining, by a submodule controller, whether the submodule is in a fault state and when the submodule is in a fault state, transmitting a fault signal to the upper level controller; and detecting, by a voltage detection unit of the submodule the initial charging voltage stored in the capacitor and transmitting the initial charging voltage to the submodule controller.

Abstract: A substation asset management method can include the steps of: determining whether to compensate a reliability model by element of the substation by comparing reliability of a reference reliability model by substation type with reliability depending on health index by element thereof generated based on state data and real-time monitoring data by element of the substation; compensating the reference reliability model by substation type and generating a unique reliability model by element of the substation as a result of the determination; evaluating system reliability and economic feasibility by maintenance scenario based on a reference system reliability model for each candidate element subject to maintenance among the elements of the substation; and drawing a maintenance scenario of the elements of the substation by using a fitness function of maintaining the substation based on the result drawn through the evaluation of the system reliability and the economic feasibility.

Abstract: A flange grounding device for grounding between flanges in the case that a predetermined interval is present due to a valve and the like being installed between the flanges when connecting pipes includes: a housing provided with an inner space in which an elastic member is installed, and provided with a rear end brought into close contact with the flange of one side; and an extension member installed inside the housing by being supported at one end of the elastic member, and provided with an opposite end protruded outer side through an inlet of the inner space to be brought into close contact with the flange of another side. Accordingly, even though the interval between the flanges is varied, grounding using one type of grounding device may be reliably performed.

Abstract: A method of controlling output of an ESS depending on droop control according to frequency variation range of a power grid in the present invention may comprise steps of: monitoring the frequency variation range of the power grid; predicting frequency correction range resulting from regulation of an engine generator during a predetermined unit regulation time if the frequency variation range is determined to exceed a first reference value; controlling the output of the ESS with an output value determined by a frequency of the power grid according to a droop control algorithm set as a default if the predicted frequency correction range does not exceed a second reference value; and fixing the output of the ESS during the unit regulation time if the predicted frequency correction range exceeds the second reference value.

Abstract: A method of operating an ESS with optimal efficiency includes: collecting charge/discharge efficiency data of a PCS; collecting charge/discharge efficiency data of a battery depending on current state of charge of the battery; creating charge/discharge efficiency data of a unit BESS including the PCS and the battery by using the collected data; determining optimal charge/discharge levels of at least two unit-BESSs included in the ESS by using charge/discharge efficiency data of the at least two unit-BESSs to satisfy commanded input/output power values of the whole ESS at a current point of time; and charging or discharging the at least two unit-BESSs depending on the determined optimal charge/discharge power values.

Abstract: A movable part of a circuit breaker for a gas-insulated switchgear is proposed. The movable part includes a puffer cylinder, a nozzle, and a main contact. An outer rib at the rear end of the nozzle is hooked to a hook rib at the front end of the hook part of the puffer cylinder. A chamber guide is provided inside the puffer cylinder so that the nozzle is immobilized. The main contact is mounted on the outer surface of the front end of the hook part. Thus, the number of components constituting the movable part of the circuit breaker is reduced, and the number of bolting points is reduced, thereby greatly reducing man-hours in an assembly work and preventing a main contact separation from occurring due to bolt loosening.

Abstract: An ESS charging and discharging operation method may include the steps of: checking whether SOC of the ESS is within an operable range, and performing an SOC management operation if the SOC of the ESS is not within the operable range; performing, if the SOC of the ESS is within the operable range, a catenary wire voltage control operation based on range of catenary wire voltage and range of variation rate of the catenary wire voltage; performing the SOC management operation after the ESS is charged or discharged depending on the catenary wire voltage control operation over unit time, if output current of the ESS does not exceed current reference value; and stopping the catenary wire voltage control operation and switching the operation to a standby state.

Abstract: An asset management method for a substation includes deriving an optimal management plan by each element of the substation depending on integrity of the each element of the substation and deriving an optimal unique reliability model for each element of the substation through a process of compensating a reference reliability model of each substation type and an apparatus executing the method.

Abstract: A pipe support device for a transformer is proposed. A brace having a grid shape and serving as a reinforcing member is provided on the surface of an outer housing constituting the exterior of the transformer. Supports are installed at predetermined intervals on the brace to be orthogonal thereto. A support base is positioned on each of the supports, and a pipe holder is coupled to the support base to support a pipe. An elastic supporting pad is positioned between the support base and the pipe and opposite flange portions of the pipe holder are seated on and coupled to the elastic supporting pad. An elastic close-contact pad is positioned between the pipe and an arched portion of the pipe holder and is brought into close contact with the pipe.

Abstract: A DC circuit breaker capable of blocking a fault current flowing through a DC line when a fault occurs in the DC line is proposed. The DC circuit breaker includes a main switch connected to a first DC line at one end and connected to a second line at the other end; a first circuit unit connected in parallel to the main switch; and n second circuit units each connected in parallel to the main switch, wherein the first circuit unit is composed of a series connection of an inductor, a first capacitor and a first switch, the inductor or the first capacitor being connected to the first DC line and the first switch being connected to the second DC line.

Abstract: The method of manufacturing the insulation member includes manufacturing a 3D printing material using a mixed material in which one or more materials selected from among polycarbonate (PC), polybutylene terephthalate (PBT), acrylonitrile-butadiene-styrene (ABS), polyamide (PA), polyoxymethylene (POM), and polyethylene terephthalate (PET), one or more fillers selected from among TiO2, SiO2, and AlO3, and a curing agent are mixed, and which contains different amounts of the fillers at predetermined intervals in a longitudinal direction, and sequentially stacking the manufactured 3D printing material using a 3D printer to thus manufacture a target insulation member so that the mixed material containing different amounts of the fillers at predetermined intervals in a longitudinal direction of the insulation member is sequentially stacked.

Abstract: Provided is a switching control method for an isolated bidirectional DC-DC converter, wherein the isolated bidirectional DC-DC converter connected between a DC grid system and a battery uses multiple switching controls together depending on a voltage of the battery, thereby facilitating high efficiency control. In the isolated bidirectional DC-DC converter according to the present invention, switching of a first switching unit and a second switching unit is controlled to control the flow of power by changing the bidirectional DC-DC voltage between the DC grid system and the battery, and the first and the second switching unit are switched using PSM switching control, SPWM switching control, and DPWM switching control together depending on a voltage with which the battery is charged and load capacity, thereby enhancing efficiency of the system.

Abstract: A connection structure of a plurality of switching modules that reduces required insulation voltage significantly when the plurality of switching modules is connected to each other in series is proposed. A switching module connection structure includes: n (n?1, integer) switching modules arranged in two or more columns and all connecting to each other in series from a first switching module in a first column to a last switching module in a last column; and insulating members disposed between at least some switching modules for each column.

Abstract: Provided is a system for seamless power conversion in DC power distribution, the system including power conversion devices connected in parallel, and performing conversion from a AC voltage to a DC voltage between an AC power distribution network and a DC power distribution network, wherein a master power conversion device among the power conversion devices converts the AC voltage supplied from the AC power distribution network into the DC voltage including an AC voltage at a preset level, and supplies the DC voltage to a DC power distribution line of the DC power distribution network, and the remaining power conversion devices that are slave power conversion devices detect the DC voltage at the DC power distribution line in real time, and when the AC voltage is not sensed from the detected DC voltage, one of the slave power conversion devices is converted into a master power conversion device.

Abstract: An apparatus for detecting internal defects in a transformer is provided. The apparatus detecting internal defects that arise in the interior by integrating an electrode for electrically detecting defects and a sensor for detecting internal gas into a single body and inserting same into the interior. The apparatus for detecting internal defects in a transformer according to the present invention comprises: a metal member of a set length; a plurality of electrodes, disposed around the metal member, for detecting electrical signals generated due to internal defects of the transformer; an insulating member formed so as to contain the metal member and plurality of electrodes; and a gas sensor, installed at the end of the metal member, for detecting gas inside the transformer.

Abstract: A method for estimating lifespan of a battery in accordance with the present invention, comprising steps of: fully discharging the battery; partially charging the fully discharged battery under a predetermined charging condition; acquiring pieces of voltage information at multiple specific points of measurement time while partially charging the battery; and calculating remaining capacity of the battery by using the acquired pieces of voltage information.