52results about How to "Negligible cost" patented technology

The invention relates to a ladle furnace use nitrogen gas nitrogen alloying process. The process comprises the following steps: a) smelting nitrogen-contained stainless steel, controlling the components of the molten steel except the nitrogen to the targeted components, and controlling a nitrogen flush initial temperature at 30 to 50 DEG C above a refining treatment out-station temperature; b) during the nitrogen bottom blowing for the smelting of the nitrogen-contained stainless steel in the LF furnace, adding 1 to 20 ppm of nitrogen to each standard cube of nitrogen; c) during the nitrogen bottom blowing for the micro-alloying treatment, controlling the nitrogen flow at 6 to 120m<3> / h and the nitrogen flush pressure at 0.60 to 0.80 MPa; and d) when the nitrogen bottom blowing is finished, carrying out the argon bottom blowing for 4 to 6 minutes with the argon flow of 2 to 20 m<3> / h so as to average the stainless steel components and temperature. The process adds the nitrogen alloying function through the nitrogen bottom flowing to the ladle furnace (LF) in the prior stainless steel production process so as to replace a nitro alloy, make the nitrogen-contained stainless steel carry out continuous and stable nitrogen alloying in the ladle furnace, improve the purity of the molten steel, and consequently improve the molten steel quality and reduce the production cost.

A method for downloading electronic file coordinately includes submitting file download task to file download device by user terminal, applying file download by file download device actually and then feeding result back to user. The download system used for realizing said method is also disclosed.

The invention relates to a self-supporting construction method for a multilayer underground structure next to an existing building. When the distance between a proposed underground building and the existing building is within 15 meters, the construction method is adopted, and the method specifically comprises the following operation steps: 1, supporting pile construction; 2, developing and controlling an earthwork of a negative first layer; 3, controlling holes at a frame column position and setting a retaining wall; 4, carrying out the construction of frame columns of a negative second layer; 5, carrying out the construction of top beams and plates of the negative second layer and columns, beams and plates of the negative first layer; 6, mounting horizontal steel supports; 7, developing and digging the earthwork of the negative second layer; and 8, carrying out the construction of other structures of bottom plates, walls and the like of the negative second layer according to a conventional method. The method skillfully uses the rigidity of an underground engineering structure self to provide a supporting point for the supporting pile so that the supporting pile is changed into a three-span indeterminate member from a cantilever member, so the bending moment load effect of the supporting pile is greatly reduced, then the designed pile length and section area of the supporting pile can be greatly reduced, the construction cost is saved by about over 35 percent, and the integral construction progress of the underground structural engineering is accelerated.

The invention discloses a seam structure of a prefabricated sectional type concrete bridge and belongs to the field of bridge engineering. On the basis that a conventionally-used formwork is basically not changed, protruding blocks and corresponding grooves are prefabricated at the two ends of each section, and hole channels of connecting reinforcing steel bars are reserved in each protruding block. After the sections are spliced, the connecting reinforcing steel bars penetrate into the reserved hole channels and anchored. The section connecting portions are squeezed tightly, a seam between the prefabricated sections is high in shearing strength, the bending performance of a bridge body is enhanced, and cracking of the bottom of the seam is delayed. Even though a crack appears, the crack can be effectively prevented from being expanded through the connecting reinforcing steel bars, and therefore the bearing capacity of the bridge body is improved. Compared with the prior art, the structure is convenient to construct, the integrality of the bridge established through the structure is good, and the mechanical property of the seam is greatly improved.

The invention discloses a flexible cable used for a new energy automobile. The cable comprises a conductor and an insulation layer used for wrapping the conductor. The outer part of the insulation layer is provided with a cooling layer in a wrapped manner, and at least one cooling medium channel extended along the length direction of the insulation layer is disposed in the cooling layer, and is used to introduce the cooling medium for the cooling and the heat dissipation of the insulation layer. Heat energy radiated by the insulation layer outwardly is effectively, reliably, quickly, and greatly eliminated by the cooling medium, and then the heat energy radiated on the outer part of the cooling layer is reasonable, controllable, and safe, and then the special use requirement of the new energy automobile is satisfied. The flexible cable is in service and operated reliably, safely, and stably in various severe environments, and has advantages of simple structure, convenient forming, small forming difficulty, low forming costs, compact structure, good flexibility, excellent heat dissipation effect, high flame resistant performance, high reliability, good safety performance, and strong practicability.

The invention relates to a diluted alkali recycling system of a mercerizing machine. The diluted alkali recycling system comprises a diluted alkali tank, a temporary diluted alkali storage container, a stirrer arranged on the temporary diluted alkali storage container, a hydrogen peroxide supply system connected with the temporary diluted alkali storage container, a pneumatic valve, a first filter, a second filter, a concentrated alkali tank, an automatic alkali matching tank, an automatic alkali matching tank control cabinet and a matched alkali liquor storage tank. The diluted alkali tank, the temporary diluted alkali storage container, the first filter and the automatic alkali matching tank are connected through a pipeline in sequence. The concentrated alkali tank, the second filter and the automatic alkali matching tank are connected through a pipeline in sequence. The pneumatic valves are arranged between the concentrated alkali tank and the temporary diluted alkali storage container, between the temporary diluted alkali storage container and the filter and between the concentrated alkali tank and the second filter. The automatic alkali matching tank is connected with the matched alkali liquor storage tank. The diluted alkali recycling system is short in alkali liquor recycling period, the whole system is low in manufacturing cost, and the cost is low in the producing and processing process.

The invention provides an auxiliary power starting and switching method and system for a steam turbine generator unit accident, so that once a steam turbine shuts down because of an accident, an auxiliary power starting and switching instruction is sent out immediately without any delay no matter whether electrical protection like power reversing or program power reversing is carried out. The switching method comprises the following steps: (101), when a steam turbine generator unit is in a grid-connected mode and a steam turbine trips because of a fault, a steam turbine control system sends out a shutdown signal to an electrical signal and then a next step is performed; (102), after a generator-transformer unit protection device in the electrical system receives the steam turbine shutdown signal, an auxiliary power starting and switching command is sent out immediately to a rapid auxiliary power switching device without any delay, and a next step is performed; and (103), after the auxiliary power switching device receives the starting and switching command sent by the generator-transformer unit protection device, a combined emergency power supply switch instruction is sent out firstly and then an operating power tripping switch instruction is sent out by a delay under the circumstance that the auxiliary power switching condition is met, so that auxiliary power parallel switching is completed.

The invention discloses a method for preparing a self-doped Fe-N-C oxygen reduction electrocatalyst through animal blood salting-out thermal polymerization. The method comprises the following steps: performing salting-out thermal polymerization on animal blood to obtain a precursor, removing water in the precursor to crush, putting the crushed polymer powder under inert atmosphere to perform high-temperature thermolysis, and washing, and performing vacuum freeze-drying to obtain the self-doped Fe-N-C oxygen reduction electrocatalyst, wherein the salting-out thermal polymerization refers to separating out precipitates after adding salt into the animal blood, and adding the precipitates into water to boil, wherein the salt is sodium chloride or potassium chloride. The catalyst prepared by the method has excellent oxygen reduction and electro-catalytic performance.

The invention discloses an automatic identification method for common vegetable insects on a yellow board, which comprises the following steps: (1) image acquisition: acquiring an image of a vegetable insect on the yellow board by using an imaging device; (2) carrying out zooming, rotating, shearing and target image separation processing on the image of the vegetable insect on the yellow board; (3) calculating the area, rectangularity and elongation of the image of the vegetable insect on the yellow board; (4) separating a deep-color part of the image of the insect from the background; (5) calculating the area, rectangularity and deep-color part contour projection quantity of the deep-color part image of the image of the insect; and (6) according to the shape characteristics of different kinds of insects and the calculation results obtained in the steps (3) and (5), judging and displaying the name of the vegetable insect on the yellow board. The invention relates to a method capable of carrying out automatic identification on common vegetable insects on yellow boards. The method disclosed by the invention has the advantages that principle is simple, operation is easy, and identification can be automatically carried out on common vegetable insects on yellow boards.

The invention belongs to the technical field of non-ferrous metal metallurgy, and particularly relates to a magnesium preparing process with molten state carbothermy and a magnesium smelting system. The magnesium preparing process with the molten state carbothermy comprises the steps that melted iron is prepared by melting, vacuumizing is conducted, and protection gas is filled; under protection of the right amount of argon, carbon powders and magnesia powders are continuously fed to the position below the liquid level of the melted iron in a vacuum reaction furnace in the form of gas-solid mixture, reduction reaction is conducted in the molten iron, and magnesium vapor and carbon monoxide are generated; gas is fed into a cooling device and cooled, and liquid magnesium is obtained; and theremaining gas is separated, the protection gas is recycled, and the carbon monoxide enters a gas collecting device and can be burned for generating electricity. The magnesium smelting system comprises a vacuum reaction system and a condensation collecting system which are sequentially connected. According to the magnesium preparing process with the molten state carbothermy and the magnesium smelting system, reduction reaction of the carbon powders and the magnesia powders only needs 10 seconds, the recovery rate of magnesium is greater than or equal to 90%, the purity of magnesium is greaterthan or equal to 90%, the melted iron is recycled, and continuous production is realized.

The invention discloses a method for judging abnormal change of fuel quantity based on fuel tank liquid level monitoring, which comprises the following steps of reading the liquid level of a fuel tankin real time by using an existing fuel tank oil level sensor of a vehicle, analyzing the fluctuation of the liquid level, and extracting abnormal fluctuation from the liquid level by using an algorithm to judge the abnormal change of the fuel quantity. The liquid level fluctuation in the fuel tank can be monitored in real time, and in the data processing stage after data extraction, the stabilityof the data can be checked firstly, and the data with large errors can be removed, so that the interference of non-experimental factors can be eliminated, and the abnormal event of the fuel tank canbe judged. The method also has the remarkable advantages that the control is accurate, no equipment is added, the change of the vehicle oil quantity can be monitored only through the fluctuation of the liquid level of the fuel tank, and the system can prompt customers in time.

The invention discloses a method for extracting and purifying microcystin, in particular a method for extracting high-purity microcystin MC-RR and MC-LR from a raw material of dried powder of bloom cyanobacteria harvested in the field. The method comprises the following steps of: A, crudely extracting the microcystin MC-RR and MC-LR by using methanol; B, making the crude extracting solution pass through an ODS column to finely extract the microcystin MC-RR and MC-LR; C, separating the microcystin MC-RR from MC-LR by using a semi-preparative chromatograph; and D, saving the microcystin MC-RR and MC-LR. The method for extracting and purifying the microcystin has the advantages of wide sources of raw materials, low cost, simple operating process, purity of over 97 percent of the extracted microcystin, and capacity of meeting the requirement on toxin purity for scientific research.

The invention discloses a method for preparing a composite quartz stone slab by using arsenic-containing waste residues and flotation tailings. The method is characterized in that the flotation tailings, the arsenic-containing waste residues, an unsaturated polyester, a coupling agent and a curing agent are used as raw materials, the materials are mixed, pressing is performed, solidification is performed, and therefore the composite quartz stone slab is prepared, wherein the flotation tailings are molybdenite flotation tailings or spodumene flotation tailings, the arsenic-containing waste residues are arsenic-containing waste residues obtained after flue dust treatment or arsenic-containing waste residues obtained after water treatment, and the amounts of the added raw materials are as follows: 26-55 parts by weight of the flotation tailings, 11-45 parts by weight of the arsenic-containing waste residues, 8-10 parts by weight of the unsaturated polyester, 0.001-0.0046 parts by weight of the coupling agent, and 0.001-0.005 part by weight of the curing agent. The method provided by the invention realizes solidification stabilization and recycling of arsenic in the preparation processof the composite quartz stone slab; and raw materials used in the method have a wide source and low price, the technical route is simple, leaching toxicity is qualified, and the method is convenientfor industrial implementation.

The invention discloses a positioning and cooling device for perforating a vertical plane. The device is formed by a cup I, a cup II and a drill sleeve, wherein the drill sleeve is arranged on the cup I, and the cup II is sleeved in the cup I; one end of the rectangular cup I is provided with an opening end surface, and a positioning hole with equivalent size to the drill sleeve is reserved in the middle of the opening end surface; the rectangular cup II is slightly smaller than the cup I; and an opening end surface is reserved on one end of the cup II, and a plurality of water injection orifices are reserved on the end surface corresponding to the opening end surface. When the device is used, the drill sleeve is inserted into the positioning hole on the cup I, and the cup I is adhered on a vertical wall surface or a workpiece to be perforated by using double sides adhesive tape or other adhesives, and the drill sleeve is ensured to be over against the perforating position; the cup II is filled with water, and is inserted into the cup I; and the water in the cup II constantly drops into the drill sleeve to instantly cool a drill. The device solves the problems of positioning and cooling of vertical plane perforation, and has the advantages of simple structure, convenient operation and popularization worthiness.

The invention claims a multifunctional circulating packaging box which is provided with a RFID identification card and is capable of overcoming such disadvantages of RF cards in the prior art that the price is high, the identification rate is low and wide use in the storage physical distribution management is not possible. The multifunctional circulating packaging box adopts the technical proposal that: the circulating packaging box comprises a top cover, a front panel, a back panel, two side plate composite members and a base board, wherein, the two side plate composite members comprise at least one intermediate plate and side plates symmetrically arranged on two sides of the intermediate plate. The circulating packaging box is characterized in that the front panel is inserted with a passive tag, or / and the side plates are provided with at least one of active tag or semi-passive tag. The application of the circulating packaging box in the storage physical distribution management on one hand saves the operation cost for manufacturers, importers and vendors, and on the other hand improves the efficiency of goods counting and the accuracy of the identification, thus greatly improving the intelligent management level of physical distribution, storage and relative trades.

The invention relates to an Internet-of-things relay SIM card data communication method comprising the following steps: multiple original SIM cards are inserted into an SIM card hosting server; a terminal device with a relay SIM card issues a connection request to the SIM card hosting server, first, the Bluetooth is connected with the Bluetooth of a nearby mobile phone, and then, the mobile phone sends the geographical location of a customized terminal to the SIM card hosting server via a network, and the SIM card hosting server selects and sends the most suitable original SIM card information to the terminal device; and the customized terminal device issues a data communication request, the relay SIM card sends an authentication request containing authentication parameters to the mobile phone, the mobile phone sends the authentication request to the corresponding original SIM card via a network and returns a key value of the original SIM card after authentication to the relay SIM card, and the terminal device starts data communication. By replacing an original SIM card with a relay SIM card, the problem that business cooperation costs too much is solved. The method is especially suitable for Internet-of-things applications.

The invention discloses an infrared remote control receiving circuit, which comprises a variable grain amplifier and a limiting amplifier, a band pass filter, a first comparator, a first demodulator, an output module, a second comparator, a second demodulator, an output time detector and a logic arithmetic unit, wherein the variable grain amplifier and the limiting amplifier are used for amplifying a voltage signal and controlling voltage gain; the band pass filter carries out band pass filtering on the output signal of the limiting amplifier; the first comparator compares the output signal of the band pass filter with a first preset potential; the first demodulator demodulates the output of the first comparator; the output module outputs the output of the first demodulator; the second comparator compares the output signal of the band pass filter with a second preset potential; the second demodulator demodulates the output of the second comparator; the output time detector detects whether the time the output of low-level pulse exceeds a preset time or not; the logic arithmetic unit calculates the outputs of the second demodulator, the output time detector and the first demodulator; and the gain of the variable grain amplifier is controlled by an automatic gain controller. The circuit is free from being limited by a signal duty ratio and signal duration when being used for transmitting data signal, and the gain can be correspondingly regulated according to the variation of environment noise.

The invention discloses a fuel for high temperature inflation burning in a porcelain granule rotary kiln, which is dry sawdust or rice husk. The invention uses the dry sawdust or the rice husk as the fuel for the high temperature inflation burning in the porcelain granule rotary kiln, and has the following advantages: on the one hand, when the sawdust or the rice husk is burnt, sulfides which are harmful to human body are not generated, air pollution is less, thus the sawdust or the rice husk is more environment-friendly; and on the other hand, the sawdust is foam sawdust of trees scattered down from the trees because of cutting during wood processing, the rice husk is a material separated in rice processing, the sawdust and the rice husk are rich in source and have very low material cost; in addition, the sawdust and the rice husk are products obtained directly in the wood processing and the rice processing by people, the rice husk is generally dry and can be used directly through simple processing, while partial 40 to 50 meshes of the sawdust is screened out and is processed (air-dried) simply. The processing cost can be negligible, and compared with pulverized coal, the comprehensive cost of the sawdust or the rice husk is only one-third of that of the pulverized coal.

The invention discloses a method for preparing recombinant bombyx mori acetylcholinesterase for detecting pesticide residues. The method comprises the following steps: connecting a bombyx mori acetylcholinesterase gene with an anchoring protein gene Agalpha1, inserting into a yeast expression vector pPIC9K to establish a surface display vector and convert pichia pastoris GS115, screening positive recon, performing inductive expression on positive recon by using methanol, centrifuging to remove the supernate after the expression is ended, and performing freeze-drying on the bacterium, thereby obtaining recombinant bombyx mori acetylcholinesterase. The prepared recombinase is good in stability, simple to operate, low in detection limit, high in sensitivity, low in cost, capable of performing in-situ detection in families, markets, vegetable production bases and the like, very applicable to screening of a great amount of samples, and has significant practical application and popularization meanings.

The invention discloses a hollow extrusion integrated plastic clamping plate, and a production process and equipment thereof. The hollow extrusion integrated plastic clamping plate comprises a lower supporting plate, supporting seats, support bars, upper support bars, straight slots, side slots, interval slots and hollowed-out slots. The production process of the hollow extrusion integrated plastic clamping plate comprises the following technological steps of feeding, extrusion, hollow forming, slot forming, cooling setting and cutting. The production equipment of the hollow extrusion integrated plastic clamping plate comprises an extruder, a mold, a die cutting machine, a cooling setting machine, a first conveyor belt, a cutter and a second conveyor belt. The hollow extrusion integrated plastic clamping plate can flexibly adapt to the hollow rato according to the bearing requirements, and materials are saved. Various types of different materials can be adopted to be mixed for molding.The hollow extrusion integrated plastic clamping plate is flexible in use and high in universality. The equipment and the mold are low in cost, flexible in manufacturing, applicable to products on different occasions and high in production efficiency.

The invention discloses a method for extracting and purifying microcystin, in particular a method for extracting high-purity microcystin MC-RR and MC-LR from a raw material of dried powder of bloom cyanobacteria harvested in the field. The method comprises the following steps of: A, crudely extracting the microcystin MC-RR and MC-LR by using methanol; B, making the crude extracting solution pass through an ODS column to finely extract the microcystin MC-RR and MC-LR; C, separating the microcystin MC-RR from MC-LR by using a semi-preparative chromatograph; and D, saving the microcystin MC-RR and MC-LR. The method for extracting and purifying the microcystin has the advantages of wide sources of raw materials, low cost, simple operating process, purity of over 97 percent of the extracted microcystin, and capacity of meeting the requirement on toxin purity for scientific research.

The invention discloses a buckle RFID (radio frequency identification) luggage tag which is characterized by comprising a luggage tag locking and positioning device and an RFID tag device, the luggage tag locking and positioning device comprises a buckle upper body and a buckle lower body, a connecting portion of the buckle upper body and the buckle lower body is U-shaped and easily bent, the RFID tag device comprises an RFID clamping plate, the RFID clamping plate is of a disc-shaped structure with an internal groove and integrally connected with the buckle lower body, an RFID tag is arranged in the groove of the RFID clamping plate, and an RFID tag cover plate covers the RFID tag. The buckle RFID luggage tag is applied to a common luggage tag and can be conveniently and rapidly operated within a short time, the calculated average application cost of every time is greatly reduced and can be ignored, and the problem of high application cost of the RFID technology in the aviation field or the logistics field is solved.

The invention discloses a red clay phosphorus adsorbent which comprises, in parts by weight, 115-145 parts of red clay particles, 20-30 parts of diatomite, 10-15 parts of glass powder and 3-10 parts of marble powder. The preparation process comprises the steps: preparing the red clay particles, weighing the raw materials, crushing, calcining, mixing and the like. The red clay has good phosphorus adsorption performance, and has the advantages of rich resources, wide distribution range and low cost; meanwhile, the red clay is a natural environment-friendly material, and does not cause secondarypollution and other problems after being put into sewage bodies, so that the red clay has great development potential in the aspect of phosphorus adsorption.

The invention provides self-doped nitrogen biomass porous carbon as well as a preparation method and application thereof, and belongs to the technical field of electrochemistry. According to the invention, blood is used as a raw material, under the action of an inorganic base pore forming and a fluxing agent, a two-step carbonization process is carried out, and the self-doped nitrogen biomass porous carbon material is obtained after acid pickling. The self-doped nitrogen biomass porous carbon obtained by the invention can effectively accelerate the electron transfer speed, and the higher specific surface area is beneficial to the transmission and storage of lithium ions. The lithium ion capacitor prepared from a biomass porous carbon negative electrode material obtained by the preparation method is excellent in electrochemical performance and long in cycle life. The raw materials are low in price, easy to obtain, green, environmentally friendly and renewable, the requirement for equipment in the preparation process is low, the preparation method is simple and economical, operation is convenient, large-scale production is easy, and huge potential application value is achieved.

The invention discloses a method for preventing and controlling greenhouse vegetable aphids and belongs to the technical field of horticultural cultivation. The method for preventing and controlling greenhouse vegetable aphids comprises the steps of cultivating thick growth of Artemisia argyi; releasing Coccinella septempunctata or Chrysopa perla; planting crops; hanging yellow insect-sticking boards; and harvesting the crops. According to the invention, aphids are prevented and controlled through the co-action of Artemisia argyi, Coccinella septempunctata or Chrysopa perla and the yellow insect-sticking boards; specifically, aphids are attracted to tender leaves of Artemisia argyi through sitotaxis of the aphids to the tender leaves of Artemisia argyi, Coccinella septempunctata or Chrysopa perla is released to prey on the aphids, and the yellow insect-sticking boards are hung above the Artemisia argyi so that the winged aphids are attracted to the yellow insect-sticking boards and cannot escape through characteristic of the aphids moving in response to yellow. The co-action of the Artemisia argyi, Coccinella septempunctata or Chrysopa perla and the yellow insect-sticking boards brings good aphid control effect, crops can be prevented from being damaged by aphids, the population density of aphids in a field can be rapidly and effectively reduced, pesticide residues and aphid drug resistance cannot be caused, and physical and biological aphid control is achieved.

The invention claims a multifunctional circulating packaging box which is provided with a RFID identification card and is capable of overcoming such disadvantages of RF cards in the prior art that the price is high, the identification rate is low and wide use in the storage physical distribution management is not possible. The multifunctional circulating packaging box adopts the technical proposal that: the circulating packaging box comprises a top cover, a front panel, a back panel, two side plate composite members and a base board, wherein, the two side plate composite members comprise at least one intermediate plate and side plates symmetrically arranged on two sides of the intermediate plate. The circulating packaging box is characterized in that the front panel is inserted with a passive tag, or / and the side plates are provided with at least one of active tag or semi-passive tag. The application of the circulating packaging box in the storage physical distribution management on one hand saves the operation cost for manufacturers, importers and vendors, and on the other hand improves the efficiency of goods counting and the accuracy of the identification, thus greatly improving the intelligent management level of physical distribution, storage and relative trades.

The invention relates to a preparation method of metal nanometer powder, in particular to a nanometer iron powder special for shielding electromagnetic wave and radar wave in a glass cockpit of an airplane. The nanometer iron powder solves the problem that the existing nanometer metal powder can not completely shield the electromagnetic wave and the radar wave in the glass cockpit of the airplane. The preparation method comprises the steps of: machining raw materials into nanometer iron powder which has the shape of spheriform powder grain and has special stealth technology under the conditions that the temperature is -5 to 0 DEG C and the high-frequency cutting times is 5500-6000 times / minute; respectively screening out the powder material with centralized grain distribution with D3=21nm, D25=22.1nm, D50=25nm, D75=27.2nm and D97=30.3nm; and packaging in an anti-oxidation way, processing a surface and filling magnetism. The nanometer iron powder solves the problems of the film coating of an ion metallic coating reflecting film and the maintaining when in use, and can block the electromagnetic wave radiation between instruments of the airplane and the external part of a cockpit of the air such as equipment of aviators.

The invention discloses a combined optimization method for protection locking based on busbar protection and quick-cutting device for high power plants, which belongs to the field of relay protection for power plant generator-transformer units. Solve the defect that the quick-cut device cannot be locked after the protection action of the high-voltage plant busbar, causing the quick-cut device to close the high-voltage backup circuit breaker to the faulty busbar. In this method, the secondary tripping circuits of the high-voltage working incoming line circuit breaker and the high-voltage standby incoming line circuit breaker for busbar protection are firstly optimized and transformed, and the closing command of the high-voltage standby incoming line circuit breaker of the blocking fast-cutting device after the busbar protection action is realized and self-maintained ; At the same time, optimize the abnormal voltage blocking logic of the fast switching device, and increase the bus fault judgment logic to block the fast switching device. The invention only needs to add a small amount of secondary equipment and reform part of the circuit, and modify the software logic and fixed value of the fast cutting device to realize it, which is simple and easy.

The invention discloses a power plant transformer residual magnetism automatic discrimination system and method. The system comprises an excitation system, a magnetic field circuit breaker FMK, an excitation coil, a generator, a first current transformer, a second current transformer, a high plant transformer, a main transformer, a grid-connected circuit breaker, a first circuit breaker, a 6kV working A section, a second circuit breaker, a 6kV working B section and a generator-transformer group protection device. The excitation system is connected with the excitation coil through the magnetic field circuit breaker, the excitation coil is coupled with the generator, the output end of the generator is divided into two paths after passing through the first current transformer, one path is connected with the high-voltage side of the high-voltage transformer through the second current transformer, and the other path is connected with the system through the main transformer and the grid-connected circuit breaker. The low-voltage side of the high-voltage plant transformer is divided into two paths, one path is connected with the 6kV working section A through the first circuit breaker, the other path is connected with the 6kV working section B through the second circuit breaker, and the system and the method can automatically identify whether residual magnetism influencing starting of a unit exists in the transformer or not.