Abstract: An earth leakage circuit breaker includes a current sensing unit configured to sense current in a circuit, a converter configured to detect a fundamental wave component and a specific harmonic component from the sensed current, the specific harmonic component being one of a plurality of harmonic components, and a controller. The controller is configured to compare a harmonic component ratio with a threshold component ratio, to determine whether the sensed current is abnormal current, and to control cutoff of the circuit according to the result of determination. The harmonic component ratio is a ratio of the specific harmonic component to the fundamental wave component. The converter is configured to convert the sensed current from an analog signal into digital data and to perform Fourier transform with respect to the converted digital data to detect the fundamental wave component and the specific harmonic component.
Abstract: A device for protecting an inverter include a first power switch configured to be turned on when a first voltage signal from a first switch of a safety relay is applied thereto; a second power switch connected in series with the first power switch, wherein the second power switch is configured to be turned on when a second voltage signal from a second switch of a safety relay is applied thereto; and a power line for connecting the first power switch and the second power switch to each other in series and for connecting the series of the first power switch and the second power switch to a buffer of the inverter, wherein a third voltage signal is applied via the power line to the buffer.
Abstract: A switch assembly of a reactive power compensation apparatus may include a first switching module having a first stack structure perpendicular to a supporting module, a second switching module having a second stack structure perpendicular to the supporting module, the second switching module being connected in parallel with the first switching module, and first and second supporting members disposed above and below the first and second switching modules.
Abstract: The present invention relates to a device for driving a motor, the device comprising: a main housing for accommodating a circuit module therein, wherein a top of the main housing is partially opened to define an open portion; an input/output (IO) cover coupled to the main housing so as to occupy the open portion; and an auxiliary housing coupled to the main housing at an vertical side face of the main housing.
Abstract: The present disclosure relates a method of detecting an electrical disturbance by a DC component in a digital protective relay, which includes acquiring a sample value by sampling an input signal at a regular cycle, detecting the electrical disturbance based on a difference between a sampled first sample value and a second sample value after the first sample value, and when the electrical disturbance is detected, detecting the DC component based on a difference between the second sample value and a third sample value after the second sample value and a difference between the third sample value and a fourth sample value after the third sample value.
Abstract: The present disclosure provides a protective glass for a solar cell module having improved power generation efficiency of a solar cell obtained by minimizing reflection of light incident onto the protective glass, and a manufacturing method for the same. The protective glass for a solar cell module includes a plurality of glass beads formed in a spherical or hemispherical shape and arranged in the horizontal direction. The plurality of glass beads is disposed on at least one of the upper and lower portions of the sealing member. In addition, the method of manufacturing a protective glass for a solar cell module includes preparing a plurality of glass beads formed in a spherical or hemispherical shape, arranging the glass beads in a horizontal direction, and injecting a molten glass solution into the glass beads and forming the protective glass.
Abstract: Disclosed herein are a device and a method for changing a setting value of electric power equipment. The method for changing a setting value of electric power equipment, includes transmitting a data request signal including a predetermined communication address and receiving a response signal corresponding to the data request signal from a slave communication module corresponding to the communication address using the serial communication network, determining whether communication between the master communication module and the slave communication module is established normally on the basis of the data request signal and the response signal, receiving, from the response signal, model information of a slave communication module in which a setting value change event occurs among slave communication modules of which communications are established normally, and discriminating and displaying, among the slave communication modules of which the communications are established normally, a slave communication module.
Abstract: The present disclosure relates to a hierarchical type power control system. The hierarchical type power control system connected to a cloud server includes: a first microgrid cell including a first energy storage system (ESS) having an uninterruptible power supply (UPS) structure and a first load that a power state thereof is managed by the first ESS; a second microgrid cell including a second load and a second ESS managing a power state of the second load; a third microgrid cell including a third load; a middleware server communicating with the first to third microgrid servers; and an integrated control system communicating the middleware server and integrally controlling power supply states of the first to third microgrid cells, wherein the first microgrid cell and the second microgrid cell are connected to each other through a converter to interchange power therebetween.
Abstract: The present disclosure relates to a method for setting a link speed of a dual port switch, and more particularly, to a method for setting a link speed of a dual port switch, which controls link speeds of ports, which are included in the dual port switch using a cut-through packet switching scheme, to be equal to each other.
Abstract: The present disclosure relates to an interface conversion device of a programmable logic controller (PLC) system and a PLC system thereof. The interface conversion device of a PLC system according to an embodiment of the present disclosure is an interface conversion device that is applied to a PLC system including a base unit that controls an operation of the PLC system, a plurality of expansion modules that operate under the control of the base unit, and an interface that is a communication line between the base unit and each of the expansion modules, and is configured to connect between a first interface for parallel communication and a second interface for serial communication.
Abstract: The circuit breaker according to the present invention comprises: a pair of contact mechanisms for switching a pair of circuits; a switching mechanism for driving the pair of contact mechanism to a circuit opening position or a circuit closing position; a trip bar rotatable to a first position for latching the switching mechanism or to a second position for releasing the switching mechanism; and an instant trip mechanism for pressing the trip bar to rotate to the second position, wherein the instant trip mechanism comprises a pair of armature assemblies and movable to a position for pressing the trip bar to rotate to the second position; and a pair of electromagnets provided to face the pair of armature assemblies and applies a magnetic attractive force to the pair of armature assemblies in response to the fault current on the circuit requiring an instant trip.
March 7, 2018
Date of Patent:
June 2, 2020
LSIS CO., LTD.
Sanghyun Woo, Jeongjae Lim, Seungjin Ham
Abstract: A coupling mechanism for coupling an electronic device to an outer casing includes a plurality of hook-shaped brackets interposed between a front cover and a rear cover of the electronic device, where the plurality of hook-shaped brackets pass through an accommodation hole of the outer casing and are held to hook the outer casing while the front cover and the rear cover are coupled to each other; a plurality of main bracket-mounted portions defined in the front cover, where each of the plurality of hook-shaped brackets is mounted into each of the plurality of main bracket-mounted portions; and a plurality of auxiliary bracket-mounted portions disposed on the rear cover, where each of the plurality of auxiliary bracket-mounted portions is engaged with each of the plurality of hook-shaped brackets when the front cover and the rear cover are coupled to each other.
Abstract: Disclosed is a sensorless control system for a permanent magnet synchronous machine. The sensorless control system includes a counter electromotive force estimation unit configured to estimate a counter electromotive force using a phase voltage reference applied to an inverter and a phase current applied from the inverter to the permanent magnet synchronous machine, and a speed estimation unit configured to estimate an angular velocity and an electrical angle of a rotor of the permanent magnet synchronous machine, and the counter electromotive force estimation unit according to one embodiment of the present disclosure may maintain robust performance at a low speed by modifying some portion of a conventional Luenberger observer.
Abstract: The present disclosure relates to an initial charging system for a medium-voltage inverter and a method for controlling the system. The initial charging system comprises: a first switch for switching between a medium-voltage inverter and a power supply thereto; a second switch for switching between an output stage of the medium-voltage inverter and an electric motor; a first initial charging unit disposed between and connected to the first switch and the medium-voltage inverter for limiting an initial excitation current to be applied to the phase-shift transformer; and a second initial charging unit disposed between and connected to an input stage of each power cell and the direct current (DC) link capacitor for limiting an initial charging current in the direct current (DC) link capacitor.
Abstract: Disclosed is a device for detecting an instantaneous maximum output current of an inverting module as a peak-current thereof. The inverting module converts a direct current (DC) link voltage to an alternate current (AC) voltage, and includes three-phases legs. Each leg has lower and upper switching elements connected in series. The device includes a shunt resistor serially connected to a lower switching element of each leg of the inverting module; a current detection module configured for detecting an output current from a signal output from each shunt resistor; and a summer configured for receiving and summing the detected output currents from the current detection module and outputting the instantaneous maximum output current of the inverting module as the peak-current thereof.
Abstract: In some embodiments, a data access apparatus includes a memory device including a plurality of addresses, an address mapping unit configured to map the addresses of the memory device with respective predetermined addresses such that they correspond to each other, a data division unit, a data mapping unit configured to map respective predetermined specific addresses in regions divided by the data division unit, and a control unit configured to control the data such that the data is stored in the addresses of the memory device mapped with the respective specific addresses in the regions divided by the data division unit.
Abstract: In some embodiments, an inverter system may include a plurality of inverters. In some embodiments, a method of controlling the plurality of inverters may include one inverter among the plurality of inverters set as a communication master to control other inverters set as communication slaves, may include the steps of generating a communication master signal in the communication master to transmit to the communication slaves, may verify whether or not the communication master signal is designated to be received by the communication slaves when the communication slaves receive the communication master signal, and may transmit a response signal with respect to the communication master signal to the inverters of the inverter system according to the verification result.
Abstract: The present invention relates to an apparatus for controlling a solar light voltage, which is capable of decreasing an output stage voltage of an AC EMC filter by connecting a load to an output stage of the AC EMC filter. The apparatus includes: a DC filter configured to receive a DC voltage from a DC solar module and reduce a noise of the DC voltage; an inverter configured to convert the DC voltage with the reduced noise into an AC voltage; and an AC filter configured to reduce a noise of the AC voltage and output the AC voltage with the reduced noise to a power system through an output stage.
Abstract: The present disclosure provides a device for eliminating a slope in an output voltage of a switcher power converter of a PLC module, by which a power supply timing of an internal regulator circuit applied to a PLC power supply is secured and an initial start condition (specification) required by the circuit element is satisfied by eliminating a slope phenomenon occurring in an output voltage from the internal regulator circuit when an external input voltage to the PLC module increases or decreases gradually.
Abstract: A hierarchical power control system associated with a cloud server includes a first microgrid cell, a second microgrid cell, a third microgrid cell, a middleware server, and an integrated control system. The first microgrid cell includes a first energy storage system (ESS) having an uninterruptible power supply (UPS) structure and a first load having a power state managed by the first energy storage system (ESS). The second microgrid cell includes a second load and a second energy storage system (ESS) for managing a power state of the second load. The third microgrid cell includes a third load. The middleware server communicates with the first to third microgrid cells. The integrated control system receives power supply-demand state information of the first to third microgrid cells through the middleware server, and establishes an integrated operation schedule based on the received power supply-demand state information of the first to third microgrid cells.