71results about How to "Stable fluctuation" patented technology

The invention relates to a method and device for monitoring dynamic current capacity of aerial power line, comprising: 1) equipping the neutral wire having the same material and size with the live wire parallel with the live aerial power line, wherein, the temperature of the neutral wire is set to be T, and the actual temperature of the live wire of the actual line is set to be T; 2) the computing formula of the line dynamic current capacity is given; 3) calculating the equivalent wind-speed coefficient M; 4) calculating the line dynamic current capacity Imax, i.e. the value of the line dynamic current capacity. The invention eliminates the meteorology parameter variation thereby simplifying calculation and having stable result fluctuation and correct result by using special temperature measuring device to measure the temperatures of the live actual wire and the neutral wire in real time, and proposing a new algorithm which uses actual wire temperature and the temperature of wire of the same type to substitute the wind-speed and wind-direction in convection loss in the dynamic current capacity calculation.

Surface-modified titanium dioxide particles which have a surface chemically modified with a hydrophilic polymer, wherein a carboxyl group of the hydrophilic polymer and titanium dioxide are bound through an ester bonding; and a method for producing the surface-modified titanium dioxide fine particles, which comprises mixing a dispersion comprising titanium dioxide fine particles having a particle size of 2 to 200 nm and a solution of a water-soluble polymer, heating the resultant mixture to a temperature of 80 to 220° C., to thereby bind both the components through an ester bonding, and removing an unbound water-soluble polymer, to purify the resuultant particles. The surface-modified titanium dioxide fine particles exhibit excellent dispersibility and stability in an aqueous solvent over a wide pH region including a neutral range.

The present invention relates to a method for producing a phosphoric acid ester-based polymer, including copolymerizing a monomer 1 represented by the following formula (1), a monomer 2 represented by the following formula (2), and a monomer 3 represented by the following formula (3), at pH 7 or lower, in the present of a polymerization solvent having a dissolved oxygen concentration at 25° C. of 0.01 to 4.0 mg/kg. The invention also relates to a method for producing a phosphoric acid ester-based polymer, including copolymerizing the monomers 1, 2 and 3 at pH 7 or lower, in the presence of a phosphonic acid-based chelating agent. The invention also relates to a method for producing a phosphoric acid ester-based polymer from a mixed solution containing the monomer 1, 2 and 3, including obtaining a mixed solution by mixing the monomers 1 to 3 at a temperature of 10 to 50° C., initiating a polymerization within 72 hours after the mixing of the monomers 1 to 3, and maintaining the temperature of the mixed solution in the range of 10 to 50° C. until the polymerization is initiated:

wherein R¹ and R² each represent a hydrogen atom or a methyl group; and R³ represents a hydrogen atom or —COO(AO)_nX [wherein AO represents an oxyalkylene group or oxystyrene group having 2 to 4 carbon atoms; n represents an average number of added moles of AO, and is a number from 3 to 200; and X represents a hydrogen atom or an alkyl group having 1 to 18 carbon atoms],

wherein R⁴ represents a hydrogen atom or a methyl group; R⁵ represents an alkylene group having 2 to 12 carbon atoms; m1 represents a number from 1 to 30; and M represents a hydrogen atom, an alkali metal or an alkaline earth metal, and

wherein R⁶ and R⁸ each represent a hydrogen atom or a methyl group; R⁷ and R⁹ each represent an alkylene group having 2 to 12 carbon atoms; m2 and m3 each represent a number from 1 to 30; and M represents a hydrogen atom, an alkali metal or an alkaline earth metal.

The invention relates to a three-level ANPC convertor neutral-point voltage balance control method. The method comprises the following steps of (1) acting on a three-level ANPC convertor through an SVPWM (space vector pulse width modulation) pulse sequence; (2) detecting the voltage of the direct current side capacitor of the convertor in real time to obtain a neutral-point voltage, and comparing the neutral-point voltage with a reference neutral-point voltage to determine whether the direct current side capacitor requires charging or discharging; (3) in real time detecting the positive and negative direction of the three-phase load current of the convertor; (4) integrating detecting values of the steps (2) and (3), within every switching period, dynamically adjust the duty ratio of the zero state of the switch sequence of a three-phase bridge arm until neutral-point voltage balance, and repeating the step to maintain fluctuation of the neutral-point voltage within a relatively small range. The three-level ANPC convertor neutral-point voltage balance control method can dynamically adjust the charging and discharging time of the capacitor according to the direction of the three-phase load current and the size of the neutral-point voltage to rapidly balance of the neutral-point voltage and to maintain fluctuation of the neutral-point voltage within a relatively small range.

The invention relates to an automatic pressure stabilizing control device for steam of a methanol distillation system and a control method of the control device. The device comprises a methanol distillation pipeline, a steam work pipeline and a microcomputer control system, wherein the methanol distillation pipeline comprises a crude methanol pipeline which is connected with an inlet in the upper part of a pre-distillation tower through a crude methanol feeding adjustment valve; the steam work pipeline comprises a middle-pressure steam pipeline and a low-pressure steam pipeline; the microcomputer control system comprises a model predictive controller; the model predictive controller is connected with a DCS (data communication system) master control clip. The control method comprises a control method for the pressure of a steam buffer tank, a control method for the liquid level of a reflux tank of a pre-distillation tower, a control method for the temperature at the bottom of the pre-distillation tower, a control method for the liquid level of the pre-distillation tower, a control method for the temperature at the top of an atmospheric tower, a control method for the temperature at the bottom of the atmospheric tower, a control method for the temperature at the top of the pressurizing tower and the temperature at the bottom of the pressurizing tower, a control method for the reflux ratio of the atmospheric tower, and a control method for the reflux ratio of the pressurizing tower. The device and the method have the advantages of timely adjusting a device load and reducing the steam consumption.

The application relates to an combined heating power and cooling apparatus with energy storage for an active distribution network and its operating method. The apparatus is comprised of a generation apparatus, a generator, a waste heat recovering and absorbing heat pump, a high temperature flue gas-water heat exchanger, a medium temperature flue gas-water heat exchanger, a low temperature flue gas-water heat exchanger, a energy storing electric heat pump, a high temperature energy storing canister, a low temperature energy storing canister, a cooling tower a number of circulating water pumps and a number of valves. The operating method changes the traditional operation modes of the system “determining electricity based on heat” and “determining electricity based on cooling”, causes the system to regulate power of the generated electricity on grid, participate in the regulation of grid load, solve the problem of a limited ability of generation peak regulation due to the inter-coupling of power generation, heat supply and cooling supply.

The invention discloses a method for debugging an oxygen-rich gas adjustment system and putting it into operation, and belongs to the technical field of blast furnace oxygen-rich gas adjustment and proportion integration differentiation (PID) adjustment control. The method comprises the following processes of inspecting if regulating valve equipment is integrated, inspecting if a gas source is normal, carrying out an adjustment control by manually operation, carrying out an automatic debugging test, putting equipment into operation and testing if the operation of the equipment is normal, and carrying out a fine adjustment according to a PID adjustment method. In the invention, an oxygen-rich gas flow is controlled through the processes of a pressure adjustment and a flow adjustment of oxygen-rich gas; a desired content of oxygen is set according to technological requirements; and through a PID adjustment, it is guaranteed that an oxygen-rich gas pressure is stable and a flow of oxygen-rich gas reaches a technologically required value. The method has the advantages of setting PID parameter values fast and having a guidance effect on large-scale blast furnaces adopting a double-PID adjustment system.

The invention discloses a mixed-frequency wave suppression device for a frequency mixing test. The device comprises a supporting capacitor which is connected in parallel with two ends of a direct current bus and is used for guaranteeing voltage stability of the direct current bus, a voltage rising or dropping chipping circuit which is connected to two ends of the supporting capacity and is used for rising or dropping voltage on the supporting capacity when the voltage on the supporting capacitor is overlow or overhigh, and a controller, wherein the input of the controller is connected to the supporting capacitor and is used for detecting the voltage on the supporting capacitor; the output of the controller is connected to the control end of the voltage rising or dropping chipping circuit; when the voltage is greater than a preset first threshold value, the controller sends a control signal to make the voltage rising or dropping chipping circuit work in a voltage dropping chopping state; and when the voltage is smaller than a preset second threshold value, the controller sends a control signal to make the voltage rising or dropping chipping circuit work in a voltage rising chopping state. By the mixed-frequency wave suppression device, fluctuation of the voltage on the direct current bus can be quickly stabilized, so that the investment of a user is saved, the energy loss is reduced, and the efficiency is improved.

A load capacitor is connected to a power supply terminal of a DUT. A current detection unit detects an output current output from a power supply apparatus. A nonlinear control unit controls its output amount so as to provide a balance between an amount of charge with which the load capacitor is charged or discharged in a first period, from a first timing at which a change occurs in a load current that flows into the power supply terminal of the DUT until a second timing at which the load current matches the output current, and an amount of charge with which the load capacitor is charged or discharged in a second period, from the second timing until a third timing at which the control operation ends.

Provided is a magnetic carrier, including: a ferrite core particle; and a coating resin, in which: the coating resin has a surface resin layer and a resin composition in the stated order from a surface side thereof; the resin composition contains a resin, and an inorganic particle or carbon black that is subjected to a hydrophilic treatment; the surface resin layer contains a resin, is free of the inorganic particle or the carbon black, and has a thickness of from 0.01 μm or more to 4.00 μm or less; and a moisture percentage change between a moisture percentage when the magnetic carrier is left to stand under an environment of 30° C. and 80% RH for 24 hours, and a moisture percentage when the magnetic carrier is left to stand under an environment of 23° C. and 5% RH for 24 hours after the standing is 0.030 mass % or less.

The invention relates to a mold for producing hollow foamed floors, and belongs to the technical field of foaming floor molds. The mold is a co-extrusion mold and comprises a mold shell, an inner corerod and an outer core rod, and a main runner and an auxiliary runner are arranged in the mold shell; the inner core rod and the outer core rod are arranged in the main runner, and the outer core rodis arranged on the periphery of the inner core rod in a sleeving mode; the inner core rod comprises an inner core base body, a plurality of inner core mounting feet and a plurality of inner core rod bodies; the outer core rod comprises an outer core shell and a plurality of outer core mounting feet; a plurality of core inner mold cavities are formed in the outer core shell, and the adjacent core inner mold cavities are separated through isolation supporting plates; and the number of the core inner mold cavities corresponds to that of inner core rod bodies, and the inner core rod bodies are sleeved with the core inner mold cavities in a suspended mode. According to the mold, by means of the combined structure of the inner core rod and the outer core rod, a buffering effect can be achieved when foaming materials are transited to a foaming cavity, limited and controlled foaming can be achieved, and therefore the quality stability of products is improved.

The invention discloses a threshold value setting method. The method comprises the steps that historical performance data is obtained, and a peak value in the historical performance data is determined; whether the peak value meets a preset threshold value standard or not is judged; if yes, the threshold value is set to be the peak value. According to the obtained historical performance data, the peak value in the performance data is selected, the peak value is subjected to use standard judgement, if passed, the threshold value is set to be the peak value, and automatic setting on the thresholdvalue is achieved; due to the fact that the peak value is the peak value in the historical performance data in a period of time, the peak value fluctuation can become more stable, the peak value is set to be the threshold value, and the stability and accuracy of threshold value judgement can be improved. The invention further discloses a threshold value setting device, a server and a computer readable storage medium which have the above mentioned advantages.

The invention discloses a flotation method for copper minerals. The flotation method comprises the following steps: a, grinding and pulping copper minerals to obtain ore pulp; b, adding a vulcanization activating agent into the ore pulp in the step a, and uniformly stirring, wherein the vulcanization activating agent comprises a reducing active agent and a vulcanizing agent according to a mass ratio of 1:10-20; c, adding a flotation reagent into the mixed material obtained in the step b; and d, carrying out foam flotation on the mixed material obtained in the step c, and separating to obtain copper concentrate and flotation tailings. According to the method, the forming process of the sulfide film on the surface of the copper ore can be improved, regulated and controlled, the vulcanizing agent can be reasonably used, and the purpose of efficient flotation and enrichment of the mixed copper ore and the copper oxide ore is achieved.

The invention relates to a carburization heat treatment process of an alloy steel casting. The carburization heat treatment process specifically comprises the following steps that S1, the carburized working surface of the casting is turned to remove the adsorption layer, the oxidation layer and the machining strain layer, the non-carburized working surface of the casting is subjected to anti-seepage treatment after cleaned, and a layer of non-copper metal film is plated on the working surface after turning; S2, a furnace is installed, gas is discharged, and the methanol and acetone are selected the carburization medium; S3, heating is carried out until the carburizing temperature is subjected to first carburizing, the carbon potential is 1.0+ / -0.05%, and then oil quenching is carried outto be below Ac1; S4, the carburizing temperature is rapidly heated to carry out secondary carburization, the carbon potential is 0.75 + / -0.05%, then the furnace is cooled to 800-820 DEG C, and thetemperature is kept constant; S5, the steps S3 and S4 are repeatedly circulated for multiple times, the coasting is slowly cooling to 350-400 DEG C, the casting is subjected air cooling after being discharged from the furnace, and then the quenching and low-temperature tempering are carried out. By adopting the scheme, the carburized layer does not generate the network carbide, so that the hardness and wear resistance of the surface of a workpiece are improved.

The invention discloses an indoor positioning method, an indoor positioning device, indoor positioning equipment and a storage medium. The indoor positioning method comprises the following steps: acquiring the signal intensity and position of a currently searched Bluetooth node; Determining a plurality of candidate Bluetooth nodes according to the signal strength of the Bluetooth nodes and a preset threshold value; Calculating the density coefficient of each candidate Bluetooth node according to the coverage area of each candidate Bluetooth node; Calculating the weight of each candidate Bluetooth node according to the signal strength of each candidate Bluetooth node and the corresponding density coefficient; Calculating the position of the mobile terminal according to the position of eachcandidate Bluetooth node and the corresponding weight; Density compensation is performed by constructing the density coefficient of the Bluetooth nodes, so that the compensated Bluetooth nodes are balanced, positioning errors caused by non-uniformity of the Bluetooth nodes or abnormality of part of the Bluetooth nodes can be effectively reduced, and the positioning accuracy is improved.