摘要:
The present invention relates to a converter in which a plurality of sub-modules, each including an energy storage unit and power semiconductors, is connected in series to each other, wherein each of the sub-modules is configured by adding a simple and inexpensive auxiliary circuit unit between two half-bridge units, and thus fault current is allowed to flow into the energy storage unit of each half-bridge unit, thereby blocking or reducing the fault current. The present invention provides a converter including a plurality of sub-modules connected in series to each other, wherein each of the sub-modules includes a first half-bridge unit including a first energy storage unit, and a plurality of first power semiconductors connected in parallel to the first energy storage unit and connected in series to each other; a second half-bridge unit including a second energy storage unit, and a plurality of second power semiconductors connected in parallel to the second energy storage unit and connected in series to each other; and an auxiliary circuit unit connecting the first half-bridge unit and the second half-bridge unit; wherein the auxiliary circuit unit includes a single third power semiconductor and a single diode.
摘要:
The present disclosure relates to a DC breaker that can block a fault current generated in a direct current line, by using a unidirectional semiconductor switch device. The DC breaker includes: a mechanical switch that is connected between first and second direct current lines; a first unidirectional semiconductor switch device that transfers a resonant current to the first direct current line when the fault current is generated, so that a current of the first direct current line becomes zero; an LC resonant circuit that is charged by receiving a steady state current of the first direct current line, and generates the resonant current to the first unidirectional semiconductor switch device when the fault current is generated; and a second unidirectional semiconductor switch device that enables a capacitor of the LC resonant circuit to be charged with the steady state current of the first direct current line.
摘要:
Disclosed herein is a power supply apparatus for a sub-module controller of a Modular Multilevel Converter (MMC), which supplies driving power to the sub-module controller of an MMC connected to a High Voltage Direct Current (HVDC) system. The power supply apparatus includes a bridge circuit unit including N (N≥2, integer) energy storage units for storing a DC voltage in series-connected sub-modules in the MMC and multiple power semiconductor devices connected in parallel with the N energy storage units in a form of a bridge; and a DC/DC converter for converting a voltage output from output terminals formed between both ends of n (1≤n
摘要:
The present invention relates to a polyketone copolymer consisting of repeating units represented by general formulae (3) and (4) below, and a mixture composition thereof. The present invention has excellent has barrier properties and thus can be used for vehicle fuel tanks, vehicle hydrogen tank liners, sealed food containers, etc.
-(CH 2 CH 2 -CO)x- (3)
-(CH 2 CH(CH 3 )-CO)y- (4)
(wherein x and y denote the mol% of each of the general formulae (3) and (4) in a polymer).
摘要:
The present invention relates to a module replacement device of a high voltage direct current transmission system. In the present invention, a replacement base (40) is provided in a structure (1) by using a support member (70) such that a sub-module (30) movably provided at a fixing base (10) of the structure (1) can be replaced by being withdrawn outside of the structure (1). A rear end of a base plate (42) of the replacement base (40) is hooked to an insulation support part (9) of the structure (1), and a front end of the replacement base (40) is supported by the support member (70) hooked to one side of the structure (1). The support member (70) is provided with a turn buckle (74) so as to adjust the replacement base (40) such that the replacement base is horizontally provided thereto. The rear end of the replacement base (40) is provided with a rail connection guide (62) for matching a fixing rail (16) of the fixing base (10) provided in the structure (1) with a guide rail (51) of the replacement base (40). The rail connection guide (62) has a rail slot (64) so as to guide the fixing rail (16) to the guide rail (51) side. According to the present invention as above, the replacement base (40) can easily and firmly be provided in the structure (1) such that the module (30) can be replaced in an easy and safe manner.
摘要:
The present invention relates to a power duplication apparatus for an HVDC system and a control method therefor, and the power duplication apparatus for an HVDC system comprises: a first independent power generator receiving first input power so as to generate and output first power; a second independent power generator receiving second input power so as to generate and output the first power; a first power supplier selectively receiving the first power output, respectively, from the first independent power generator and the second independent power generator so as to convert the first power into second power having a smaller size than that of the first power and output the same; a second power supplier for selectively receiving the first power output, respectively, from the first independent power generator and the second independent power generator so as to convert the first power into the second power having a smaller size than that of the first power and output the same; a first HVDC controller for receiving the second power output from the first power supplier so as to activate the same and control an HVDC converter; a second HVDC controller for receiving the second power output from the second power supplier so as to activate the same and control the HVDC converter; and a power monitoring controller for enabling the first power output from the first independent power generator or the second independent power generator, so as to generate the first power having the same size as that of the first reference power if the first power has a size different from that of the first reference power by comparing the sizes of the first power and pre-stored first reference power, to be transferred to the first power supplier and second power supplier.
摘要:
The present invention consists of: a first HVDC converter unit which is connected to a powered electrical grid; a second HVDC converter unit which is connected to a powerless electrical grid and connected to the first HVDC converter unit through a DC transmission line so as to receive a first DC power source from the first HVDC converter unit; a voltage distributor which is connected to the DC transmission line connecting the first HVDC converter unit and the second HVDC converter unit so as to receive and distribute the first DC power source applied from the first HVDC converter unit to the second HVDC converter unit, and output a second DC power source that is lower than the first DC power source; and a DC-DC converter which is connected to the voltage distributor so as to receive the second DC power source, convert the second DC power source into actuating power for use in a HVDC controller and output the actuating power.
摘要:
The present invention relates to a high-voltage direct current (DC) circuit breaker for cutting off a fault current from flowing through a line during a malfunction in a high-voltage DC line. A DC circuit breaker according to the present invention comprises: a mechanical switch disposed on a DC line; an L/C circuit connected in parallel with the mechanical switch (110), and comprising a capacitor and a reactor connected in series to each other to generate LC resonance; a first semiconductor switch, connected in parallel to the L/C circuit, for switching the unidirectional flow of the current; and a second semiconductor switch, connected in parallel to the first semiconductor switch, for switching the uni- and reverse-directional flow of current.
摘要:
The present invention relates to a modular cooling apparatus for a high-voltage direct-current transmission system. A sub-module (10) according to the present invention comprises a power unit (12) in the front and a capacitor unit (13) in the rear, and a heat sink (30) for discharging heat generated from the interior is provided in an interior space (14') of a power unit housing (14) forming the exterior of the power unit (12). A coolant path (31) is provided in the interior of the heat sink (30). The entrance and exit of the coolant path (31) are located adjacent to the bottom surface of the interior space (14'). Connecting couplers (20) for supplying coolant to the interior space (14') are provided on the sloped surface (16) on the bottom end of the front surface (15) of the power unit housing (14). The sloped surface (16) is formed so as to face the ground at an angle. On both side surfaces of the power unit housing (14) are pass-through parts (22), each of which is provided with a louver plate (24) having louvers (26) to allow air to circulate between the interior space (14') and the outside. As such, according to the present invention, heat is dissipated more effectively while damage to the sub-module (10) due to coolant leakage does not occur.
摘要:
The present invention provides an apparatus for bypassing a phase current from a malfunctioning sub module in a converter. The converter includes multiple sub modules each having an energy storage unit, and at least one power semiconductor circuit which is connected in parallel to the energy storage unit and which includes a power semiconductor switch and free-wheeling diodes, wherein the sub modules are connected in series to each other. The bypass apparatus for a converter according to the present invention comprises: a vacuum switch tube for disconnecting between a first connection terminal and a second connection terminal of a malfunctioning sub module upon the occurrence of a malfunction in a specific sub module and bypassing a phase current from said malfunctioning sub module; and a control device for controlling the operation of the vacuum switch tube. The control device comprises: permanent magnets having different polarities and guiding the disconnecting and canceling operations of the vacuum switch tube; a core fixed to enable the permanent magnets to contact or be separated from the core; a coil wound around the core; a power source unit for applying power to the coil; and a control unit for controlling the supply of power from the power source unit to the coil upon the occurrence of a malfunction in the sub module. The control unit controls the power source unit such that the power is supplied to the coil upon the occurrence of a malfunction in the sub module and the permanent magnets are pushed out by the magnetic properties induced in the core so as to guide the disconnecting operation of the vacuum switch tube and bypass the phase current.