22 results about "Dc field" patented technology

The invention relates to the technical field of converter stations, in particular to a back-to-back converter station arrangement type based on the SLCC technology, and a power conversion unit comprises a first valve hall and a second valve hall; a direct-current field is arranged between the first valve hall and the second valve hall, and a direct-current field middle road, a smoothing reactor and a connecting reactor are arranged in the direct-current field; an LCC valve and an SVF valve are arranged in each of the first valve hall and the second valve hall; dC wall bushings are arranged on the hall walls, close to one side of the DC field, of the first valve hall and the second valve hall, and AC wall bushings are arranged on the hall walls, away from one side of the DC field, of the first valve hall and the second valve hall; the direct-current side of the LCC valve is connected to the smoothing reactor through a direct-current wall bushing, and the wire outlet side of the SVF valve is connected to the connecting reactor through the direct-current wall bushing. Therefore, the capacity transmission requirement can be met through the characteristics of the LCC valve, the dependence on an alternating current system is reduced through the characteristics of the SVF valve, the field of a conventional direct current alternating current filter is canceled, the occupied area is reduced, installation and maintenance are convenient, and the cost is reduced.

The utility model discloses a valve tower of an ultrahigh-voltage direct-current energy consumption device, and relates to the technical field of flexible direct-current power transmission engineering. Comprising a positive energy-consuming valve tower, a negative energy-consuming valve tower and a connecting pipe bus connected between the positive energy-consuming valve tower and the negative energy-consuming valve tower, the positive energy-consuming valve tower and the negative energy-consuming valve tower are symmetrically arranged in a linear manner, so that the occupied area of the direct-current field energy-consuming valve tower is reduced; each of the positive energy-consuming valve tower and the negative energy-consuming valve tower comprises an insulating support structure and a multi-layer valve switch structure; a plurality of valve layers are arranged among the multi-layer valve switch structures; the valve layer is composed of a plurality of valve sections which are bilaterally symmetrical, the left valve section and the right valve section are arranged back to back, and each layer of valve tower is in a U-shaped wiring mode, so that the types and the number of connecting pipe busbars or busbars are effectively reduced, and the structure is simpler.

The invention provides a land flexible direct current converter station direct current field arrangement system and an operation control method, and relates to the technical field of flexible direct current transmission, and the system comprises a bridge arm reactor, an isolation grounding switch, a direct current measuring device, a direct current voltage measuring device, a direct current lightning arrester, a wall bushing and an energy consumption device which are conventionally configured in a land converter station direct current field. The devices are connected through tubular buses and flexible conductors. According to the invention, a double-spliced direct current submarine cable scheme is adopted for high-capacity offshore wind power flexible direct current transmission, on the basis of conventional direct current field configuration, by adding three isolation grounding switches, no power failure can be realized when any two direct current submarine cables are in an outgoing line fault, and the reliability of high-capacity offshore wind power flexible direct current transmission is greatly improved.

The invention provides a device and a method for testing the operating characteristics of a direct-current field suppression switch, and relates to the technical field of testing the operating characteristics of the direct-current field suppression switch. The closing control loop is used for controlling closing of the first coil; the first opening control loop is used for controlling opening of the first coil; the second opening control loop is used for controlling opening of the second coil; two ends of the closing control loop, the first opening control loop and the second opening control loop are respectively connected to a power supply positive electrode and a power supply negative electrode; wherein the closing control loop comprises a first closing switch, the first coil and a second closing switch which are sequentially connected in series; the first opening control loop comprises a first opening switch, the first coil and a second opening switch which are sequentially connected in series; and the second opening control loop comprises a third opening switch and the second coil which are sequentially connected in series. According to the scheme, the problems of complex operation and low safety of the DC field suppression switch operation characteristic test can be solved.

The invention discloses an open-circuit test method and device for a direct-current power transmission system, and belongs to the technical field of power electronic transverters, and the method comprises the steps: switching a control mode of the direct-current power transmission system to a no-load pressurization test mode, switching a direct-current field switch to a no-load pressurization test state, and carrying out the open-circuit test of the direct-current power transmission system; the outer loop control in the no-load pressurization test mode is switched into the sub-module average voltage control; closing a bypass switch on the direct current side of the to-be-tested converter valve; the converter valve to be tested comprises at least one of a first converter valve and a second converter valve; closing an inlet wire switch at the alternating current side of the converter valve to be tested so as to enable the converter valve to be tested to enter a short-circuit charging state; after charging of the to-be-tested converter valve is completed, the to-be-tested converter valve is unlocked according to a first preset voltage; turning off a bypass switch on the direct current side of the converter valve to be tested; and raising the direct-current voltage of the to-be-tested converter valve according to a preset target. The system can meet the requirements of the open-circuit test of the extra-high-voltage flexible direct-current power transmission system.

The present invention discloses an offshore converter station, comprising a top station layer and a bottom station layer arranged in layers along the height direction. The bottom station layer is equipped with a valve hall and a DC field. The valve hall is equipped with a first power distribution device and a diode converter valve with a quadruple valve structure. The DC field is equipped with a second power distribution device and a smoothing reactor. The top station layer is equipped with an AC field, which is equipped with a third power distribution device and a converter transformer. A cable room is provided between the top and bottom stations, in which cables are arranged. The third power distribution device is connected to an AC submarine cable, the third power distribution device is connected to the converter transformer via a cable, the converter transformer is connected to the valve hall via a cable, and the valve hall is connected to the DC field via a cable. The smoothing reactor is arranged on the DC pole line of the diode converter valve, and the first power distribution device of the DC field uses a cable outlet. The present invention can be applied to offshore DC transmission systems with voltages reaching ±500kV and above and capacities reaching 2000MW and above.

The invention relates to the technical field of circuit breakers, and discloses a multifunctional direct-current circuit breaker which comprises a shell, leads arranged at the two ends of the shell, an anti-overload mechanism arranged on one side of the interior of the shell, an anti-short-circuit mechanism arranged at the bottom of the anti-overload mechanism and a tripping mechanism arranged on one side of the anti-short-circuit mechanism. The arc extinguishing mechanism is arranged on one side of the tripping mechanism; the short circuit prevention mechanism is used for preventing short circuit of the line, the overload prevention mechanism is used for preventing overload of the line, and the tripping mechanism is used for tripping when the short circuit prevention mechanism or the overload prevention mechanism is triggered to protect the circuit. Arc extinguishing efficiently adapts to a direct current scene, the arc extinguishing problem that the direct current does not have a natural zero crossing point is solved by assisting an arc striking electrode to actively pull and lengthen the arc and matching a funnel-shaped arc extinguishing grating and an accurate track alignment design, the arc is quickly segmented and extinguished, reignition is avoided, and the arc extinguishing device adapts to a high-voltage large-current scene.

The utility model discloses a converter station constructed through alternating current and direct current fusion in the technical field of converter stations, and aims to solve the problems that in the prior art, an alternating current transformer substation and a direct current converter station are separately constructed, land occupation is large, and facility investment is large, the converter station comprises the alternating current transformer substation and the direct current converter station, and is characterized in that the converter station is overall arranged in a square shape; the interior is divided into four square areas in two rows and two columns, and an alternating-current transformer substation area for building an alternating-current transformer substation, an alternating-current filter field area for building a direct-current converter station, a commutation and direct-current field area and a station front auxiliary area are arranged in the four areas respectively; the alternating-current transformer substation area is arranged adjacent to the alternating-current filter field area and the pre-war auxiliary area, and the alternating-current transformer substation area and the commutation and direct-current field area are arranged diagonally. The electric changing station comprises the area for building the alternating-current transformer substation and the area for building the direct-current electric changing station, the alternating-current transformer substation and the direct-current electric changing station are built together, land occupation is reduced, equipment in the two stations can be shared, and equipment configuration is reduced.

Devices and methods are described for disinfection of pathogenic organisms using pulsed DC field electroporation. For example, this disclosure describes disinfection of pathogenic organisms using pulsed DC field electroporation for lung infection treatment, blood infection treatment, sterilization, and respirators.

The invention provides an offshore flexible direct current converter station direct current field arrangement system and an operation method, and relates to the technical field of offshore wind power flexible direct current transmission engineering, the offshore flexible direct current converter station direct current field arrangement system comprises two direct current fields, the two direct current fields are symmetrically arranged, one direct current field is provided with a positive pole three-phase bridge arm reactor, and the other direct current field is provided with a negative pole three-phase bridge arm reactor; the six bridge arm reactors are symmetrically arranged in an ABCABC mode, incoming lines of the bridge arm reactors are all connected with direct-current wall bushings, outgoing lines of the bridge arm reactors are all connected with a busbar type bus in parallel, and the busbar type bus is sequentially connected with a direct-current voltage measuring device, a horizontal telescopic direct-current isolating switch, a vertical telescopic direct-current isolating switch, a direct-current measuring device and a lightning arrester. And finally, the direct-current cable terminal is connected with a direct-current cable. According to the invention, the wall bushing is arranged between the positive direct current field and the negative direct current field, and the direct current isolation switch is reasonably arranged, so that no power failure during fault maintenance of any one or two submarine cables can be realized on the premise of not additionally increasing the size of the direct current field, and the operation reliability of an offshore converter station can be improved.

The present application relates to the technical field of charging pile control, in particular to a charging control method and control system of three AC-DC hybrid piles. The method comprises: generating a charging session request and determining a candidate charging gun; in the pre-insertion identification state, keeping the main power loop switching device open, using low-energy detection to obtain vehicle-side charging capacity information, combining gun type and pile-side resource state to form compatibility judgment, if the start condition is met, entering the formal locking state and binding the session, if not, outputting guidance information to prompt switching the charging gun; then completing the channel configuration according to the gun type and performing safety verification, in the DC scenario, pre-charging and then closing the switch to start; monitoring the operating parameters during the charging process, and disconnecting the switching device and releasing the port resources when ending or abnormally. The system comprises session management, two-stage identification and channel selection, channel configuration and safety start, monitoring and end recovery modules.

The invention relates to the technical field of black-start auxiliary excitation, in particular to a black-start auxiliary excitation circuit and a wire connecting device. The system comprises an excitation silicon controlled rectifier bridge, an alternating current magnetic field circuit breaker and a direct current magnetic field circuit breaker which are electrically connected with the excitation silicon controlled rectifier bridge, an excitation transformer electrically connected with the alternating current magnetic field circuit breaker, and a generator and an alternating current branch which are electrically connected with the excitation transformer, the device comprises an AC power switch electrically connected with the excitation silicon controlled rectifier bridge, an excitation transformer electrically connected with the AC power switch, a first diode rectifier bridge electrically connected with the excitation transformer, and an auxiliary excitation control switch electrically connected with the first diode rectifier bridge. According to the black-start auxiliary excitation circuit, the problem that a conventional direct-current power supply cannot be adopted for auxiliary excitation in the excitation black-start process of a large generator set is solved, and the installation and maintenance efficiency of the black-start auxiliary excitation circuit is improved.

Method for data-independent tandem mass spectrometry (MS-MS) analysis comprising the following steps: ramping or stepping in small steps a first parent ion selection mass spectrometer (MS1) to transmit a parent ion mass window with a width of at least 10 amu (1.66054e-26 kg); Establishing rapid ion transfer through a collision cell (15, 35) to induce fragmentation of parent ions, either by axial gas flow or by an axial direct current (DC) field or by a propagating radio frequency (RF) wave; Receiving families of parent and fragment ions in an orthogonal accelerator (17, 37), frequent pulsing of the orthogonal accelerator (17, 37) with a sequence of time-coded pulses; Analyzing fragment ions in a multi-reflecting time-of-flight mass spectrometer; Collecting data that is representative of the families of ancestral and Fragment ions are detected on the multi-reflecting time-of-flight mass spectrometer in a data recording format; Decoding the sequence of time-coded pulses corresponding to the parent ion mass window to form fragment spectra based on a temporal correlation in the acquired data between fragment and parent masses; and Adjusting a scan time of the ramped or stepped operation of the parent ion selection mass spectrometer (MS1) based on a time profile of a chromatographic peak width in the acquired data obtained in a preceding chromatographic separation.

This invention discloses a demonstration tool and method for ion trapping and quadrupole mass spectrometry principles. A segmented trap assembly is fixedly mounted on a base, and a sample preparation component for storing sample particles is inserted within the segmented trap assembly. One end of the sample preparation component is connected to a gas pump. The segmented trap assembly includes four segmented rods arranged in a cross shape, each with a corresponding radio frequency electric field and DC field applied. The sample preparation component is located between the four segmented rods and is equidistant from them. Each segmented rod includes a radio frequency electrode, with a first cap electrode and a second cap electrode fixedly connected to its two ends. One end of the radio frequency electrode is electrically connected to a radio frequency electrode fixedly mounted on the first cap electrode. This invention can be used to demonstrate both the trapping principle of an ion trap and the mass selection principle of a quadrupole mass spectrometer. It has advantages such as high feasibility, simple operation, and low manufacturing cost, thus making it possible to conduct more widespread teaching demonstration experiments.

The application discloses a method for establishing and confirming a target loop of multi-terminal parallel DC engineering metal ground conversion, and specifically comprises the following steps: after a metal ground conversion command is issued, a parallel target loop is established by operating a DC field switch breaker; DC field data is acquired; firstly, the position of the DC field switch breaker is judged; if the condition is not met, it is confirmed that the target loop establishment fails; if the condition is met, the current of the target loop is continuously judged; if the condition is met, it is confirmed that the target loop establishment succeeds; if the condition is not met, the initial loop conversion switch is separated, and the current of the target loop is judged again; if the condition is met, it is confirmed that the target loop establishment succeeds; if the condition is not met, the initial loop switch is closed, and it is confirmed that the target loop establishment fails. The method can effectively overcome the defects of the prior art, has the advantages of simple and convenient process, no need for complex calculation, no need for power / current level adjustment, no need for dependence on inter-station communication, and the like, can be popularized to more terminals, effectively guarantees the safety of a power grid, and brings practical economic benefits.

The invention relates to the field of antiferroelectric ceramic materials, and discloses a lead-free antiferroelectric ceramic, a preparation method and application thereof, the chemical composition of the ceramic is (1-x-y) NaNbO3-xABO3-yLa2O3-zMnO2, A is one of Ca, Sr and Ba, B is one of Hf, Zr, Sn and Ti, x is more than or equal to 0.1 and less than or equal to 0.2, y is more than or equal to 0.05 and less than or equal to 0.1, and z is more than or equal to 0.01 and less than or equal to 0.03; the ceramic is sodium niobate-based antiferroelectric ceramic, and the capacitance density of the ceramic is increased along with the increase of the external electric field intensity (0-20 kV / mm). According to a pulse capacitor element made of the ceramic, under the condition of an alternating current and direct current coupling electric field (the alternating current electric field is 8-10 kV / mm, and the direct current electric field is 18-20 kV / mm), the variation amplitude of the maximum capacitance density of the ceramic is smaller than 8% along with the increase of the working temperature, and the temperature stability of the lead-free antiferroelectric ceramic is remarkably improved.

An ion mobility analyser is disclosed having a gas flow directed along the ion travel axis and a set of electrodes to which DC voltages are applied to establish a DC field. The opposing forces of the gas flow and DC field cause ions to be trapped within a separation region in axial regions determined by their ion mobilities. A gas recirculator, having inlet and outlet ends respectively located downstream and upstream of the separation region, supplies at least fifty percent of the gas flow within the separation region, thereby reducing vacuum pumping requirements.

The application discloses a kind of offshore wind power DC grid-connected converter station, including AC field, converter valve hall, bridge arm reactor and starting area, DC circuit breaker and energy consumption valve hall and DC field, AC field, converter valve hall, bridge arm reactor and starting area, DC circuit breaker and energy consumption valve hall and DC field are sequentially connected to make submarine cable by AC field access to the DC field DC transmission line transmission.The application can not need to set offshore converter station, offshore wind power AC power collection line is directly landed and converted into DC by converter station, and is accessed into DC power grid by DC line.

The present invention relates to a device and a method for operating a device for ion molecule reaction-mass spectrometry (IMR-MS) and / or proton transfer reaction-mass spectrometry (PTR-MS) for analyzing a gas for at least one compound to be analyzed by chemical ionization via specific types of reagent ions, the device comprising: a source of reagent ions, the device has a hollow cathode glow discharge (HCD) region (101) and a source drift (SD) region (102); a drift tube region (103) adjacent to the source of reagent ions, comprising at least one inlet (107) for the gas to be analyzed and at least one source for an electric field; a mass analyzer region (104) adjacent to the drift tube region (103); the HCD region (101) comprises at least one port (105) connected to at least one pump, at least two electrodes serving as anodes (201, 203) and at least one electrode serving as a cathode (202), the SD region (102) comprises at least one port (106) connected to at least one source gas supply, and the control device is configured to control a discharge current in the HCD region (101), controlling the source gas flow through the reagent ion source, adjusting the pressure in the drift tube region (103) between 1 and 10 hPa, adjusting the electric field in the drift tube region (103) wherein the electric field comprises at least a DC field configured to attract ions in the direction of the mass analyzer region (104).

The invention discloses a multi-physics field calculation method for an offshore flexible direct current conversion platform and a related device, and relates to the technical field of high-voltage direct current transmission. The converter platform is divided into a valve hall, an alternating-current field hall, a direct-current field hall and a GIS equipment room according to functions, three-level calculation levels of equipment, a cabin and a platform are set, equipment-level, cabin-level and platform-level multi-physical field simulation is carried out in sequence, the simulation result of the previous level serves as the excitation condition of the next level, step-by-step geometric simplified modeling is combined, and the simulation result of the next level serves as the excitation condition of the next level. And cross-scale electricity-magnetism-heat-force multi-physics field coupling analysis is realized. The problems that in the prior art, due to the fact that the model scale is too large, full-platform simulation is not feasible, and key coupling variables are difficult to identify are solved, the simulation efficiency and precision are remarkably improved, and multi-physics field equilibrium optimization design in a compact space is supported.

An apparatus for induction heating of ferromagnetic materials in which a single electromagnet is used for simultaneous generation of AC and DC fields.

The invention belongs to the technical field of offshore wind power optimization layout, and particularly relates to an offshore flexible direct current conversion platform direct current field. The problem that a traditional open type arrangement is too large in occupied area is solved. The marine flexible direct current conversion platform direct current field comprises electrical units corresponding to a direct current positive electrode and a direct current negative electrode, and each unit comprises a plurality of bridge arm reactors, a gas-insulated switch module and a gas-insulated closed confluence conductor. Wherein the output ends of the plurality of bridge arm reactors are connected to the closed confluence conductor; and the closed confluence conductor is spatially arranged above the switch module and is electrically connected with the switch module through a gas insulation connecting structure to jointly form a totally-closed gas insulation high-voltage conductive path from the output end of the electric reactor to the wire outlet end of the direct-current field. According to the invention, totally-enclosed gas insulation equipment and vertical three-dimensional layout are adopted, so that the plane size of a direct-current field is reduced, and the insulation reliability and corrosion resistance of the device in a severe ocean environment are improved.