96 results about "Arc resistance" patented technology

The invention relates to the technical field of operation and maintenance of complete switch equipment, and discloses a DMC material-based operation and maintenance method for complete switch equipment, which comprises the following steps of: determining key performance parameters such as insulating strength, heat conductivity coefficient and arc resistance of a DMC material through an experiment, and constructing an aging characteristic model; calculating a material health index based on running state data collected in real time, and dynamically generating a degradation trend and residual life in combination with a time sequence prediction algorithm; and generating a maintenance plan through an optimization model, and introducing a risk weight coefficient to realize dynamic balance between maintenance cost and equipment reliability. According to the method, through material performance modeling and multi-source data dynamic fusion, the accuracy and response speed of equipment state monitoring are remarkably improved; through multi-dimensional cooperation of trend prediction and maintenance optimization strategies, full-life-cycle closed-loop management is formed, and intelligent upgrading of operation maintenance under complex working conditions is realized.

The invention provides an arc resistance characteristic-based segmented modeling method of a fuse for a direct current networking system, and relates to the technical field of common direct current bus system design, and the method comprises the steps: calculating the real-time arc resistance data of the fuse according to the continuously collected short-circuit voltage and short-circuit current at the two sides of the fuse in a short-circuit test process, and forming an arc resistance curve; intercepting an arc resistance curve from the peak moment of the short-circuit current to the slope descending moment of the arc resistance curve to obtain an arc starting stage arc resistance curve, and intercepting an arc resistance curve from the slope descending moment to the moment when the short-circuit current is zero to obtain an arc burning stage arc resistance curve; respectively carrying out data fitting according to the arc starting stage arc resistance curve and the arcing stage arc resistance curve to obtain a sectional arc resistance curve equation; and taking the arc resistance curve equation as a control signal to build and obtain a fuse simulation model based on the controlled resistor. The method has the advantages that the arc resistance curve is divided into two sections, the corresponding arc resistance curve equation is designed, the simulation precision is higher, and the method can be better suitable for different working conditions.

A converter station AC filter group circuit breaker abnormal arcing modeling analysis method comprises the following steps: firstly, carrying out time mark alignment, amplitude calibration and filtering de-noising on wave recording signals such as AC bus voltage and filter branch current to obtain high-quality input data; then, combining a primary wiring diagram, enabling an alternating current system to be equivalent to an ideal power supply and series impedance, enabling circuit breaker arcing to be equivalent to arc resistance changing along with time, and constructing an equivalent circuit model comprising the power supply, the impedance, a capacitor, an electric reactor and dynamic arc resistance; establishing a state space equation according to a voltage and current constraint relation, and performing time domain solution by adopting a two-step two-order or three-order diagonal implicit Runge-Kutta method to obtain voltage and current responses of the whole process of the fault; on this basis, the arc resistance change is inversed according to the ratio of arc voltage to current, the current zero passage is identified through the resistance symbol change at adjacent moments, and the zero passage section is smoothed; and finally, the inversion result is verified again by means of the simplified equivalent model.

The invention relates to a characteristic interval fitting and modeling method for breakdown voltage between GIS (Gas Insulated Switchgear) disconnecting switches, which is characterized in that on the basis of an actually measured scatter diagram of breakdown voltage, optimal distribution fitting is carried out on the scatter diagram, the distribution interval is predicted, and upper and lower boundary curves are calculated, so that subsequent modeling is facilitated. On the basis of an original simulation model, randomness of breakdown voltage is introduced to be combined with a reignition arc module to form a new model, and the new model is combined with an arc quenching module, a switch control module and an arc resistance module to form a new GIS disconnecting switch dynamic reignition arc simulation model. According to the invention, simulation of switch gap arc reignition randomness and extinguishing phenomenon is realized, and then the peak value distribution condition and the maximum peak value of the VFTO are analyzed. According to the method, the simulation precision is improved, the influence of the switching operation on the VFTO can be evaluated more accurately, and the reliability analysis of an electrical system is enhanced.

The invention discloses a gas arc cooling performance detection method and a related device, and relates to the technical field of electrics. According to the method, the circuit breaker is controlled to be switched on and off at the arcing time point in the preset arcing interval corresponding to each to-be-detected gas medium, and the arcing information corresponding to each arcing time point is obtained; according to the voltage signal and the current signal between the fractures of the circuit breaker in the arcing information corresponding to each arcing time point, a target constant corresponding to each arcing time point is determined, and the target constant represents the rate at which the arc resistance value changes by the same multiple; determining a constant accumulated value according to a target constant corresponding to each arcing time point in a preset arcing interval corresponding to each to-be-detected gas medium; the constant accumulated value can reflect the accumulated strength of the cooling efficiency of the gas media to be detected on the electric arc in the arcing interval, and comparing the constant accumulated value corresponding to each gas medium to be detected to determine the electric arc cooling performance difference between the gas media to be detected.

The invention relates to the technical field of flat single-shaft tracking photovoltaic supports, and provides a flat single-shaft tracking photovoltaic power generation support and an installation method.The first-time cleaning is achieved through cooperative work of a cleaning mechanism and a reset mechanism, specifically, when a photovoltaic panel rotates from east to west, an arc-shaped abutting rod pushes a second insertion plate to compress a reset spring, a linkage gear releases a first insertion plate, and the first insertion plate is driven to rotate; the elastic pulling rope pulls the reciprocating sliding block to drive the rubber scraping strip to scrape the photovoltaic panel in one direction. And when the photovoltaic panel is reset to the east, a steering rod drives a second gear to drive a first gear, a rectangular pushing frame is pushed to slide along a T-shaped sliding way through a telescopic rod and a connecting rod, a reciprocating sliding block is forcibly reset to the starting point, and a rubber scraping strip scrapes the panel again in the reset process. The photovoltaic panel is completely utilized to track natural rotation of the sun to drive cleaning, extra energy or a control system is not needed, a comprehensive cleaning tracking process and a resetting process are automatically completed twice every day, the power generation efficiency is effectively improved, and manual maintenance is reduced.

The invention discloses an electromagnetic shielding foam material and a preparation forming method thereof, and relates to the technical field of polymer processing. The electromagnetic shielding foam material is prepared by adopting polyphenylene sulfide as a raw material, so that the mechanical strength of the electromagnetic shielding foam material is high, and PPS has excellent mechanical strength, tensile strength, bending strength and other indexes which are at a relatively high level in engineering plastics, and can bear relatively high pressure and wear; the melting point of the PPS exceeds 280 DEG C, the heat distortion temperature exceeds 260 DEG C, the PPS can resist the high temperature of 260 DEG C in a short term, the long-term use temperature can reach 200-220 DEG C, and the PPS still can keep good performance at the high temperature; the PPS has excellent electrical insulation property, low dielectric constant and dielectric loss angle tangent value and good arc resistance, and is suitable for insulating materials in the field of electronic and electric appliances; excellent chemical corrosion resistance and radiation resistance are realized; the PPS electromagnetic shielding foam material prepared by a special process also has a good electromagnetic shielding effect, and can be used in occasions requiring electromagnetic shielding.

The invention discloses a simulation model and a simulation method for the whole operation process of an AI disconnecting switch, and the model comprises the steps: connecting the disconnecting switch with an arc resistor and an arc inductor to form a series branch, and then connecting the disconnecting switch with a fracture capacitor to form a parallel branch, which is used for simulating the arc breakdown characteristics of a switch gap in the operation process of the disconnecting switch; the re-arcing module is used for judging whether voltage across the gap of the disconnecting switch breaks down or not and outputting a re-arcing signal; the arc quenching module is used for acquiring a current signal of the series branch, judging whether the current signal meets an arc quenching criterion or not, and outputting an arc quenching signal; the arc-extinguishing ending module is used for judging whether the current signal meets an arc-extinguishing ending criterion or not and outputting an arc-extinguishing signal; the switch control module is used for controlling on and off of the isolating switch; the arc resistance control module is used for controlling the resistance change of the arc resistor based on the reignition arc signal, the arc quenching signal and the arc quenching ending signal; and the timing module is used for recording the gap breakdown time of the disconnecting switch and the starting time and the ending time of the arc quenching stage.

The invention discloses an LF furnace voltage and current gear parameter determination method capable of reducing power consumption. The method comprises the following steps: step 1, determining a selection range of arc current; 2, acquiring circuit resistance r and arc resistance Rarc, and calculating to obtain operation reactance Xop; 3, calculating to obtain an operation resistance Rop and an operation impedance Zop; 4, working current I, active power P, reactive power Q, apparent power S, arc power Parc, electric efficiency eta and temperature rise speed v are obtained through calculation; and fifthly, an electrical characteristic curve is drawn through matalab software, the most economical current and the current with the fastest temperature rising speed are selected, and therefore the power consumption of the LF furnace can be effectively reduced in actual production. The database technology is utilized, the economic current and the current with the fastest heating speed under each voltage gear are obtained, the reasonable power supply system can not only improve the production efficiency, but also reduce the energy consumption and save the energy, and the method has important significance for saving the refining cost, shortening the smelting time, saving energy and reducing emission.

The invention provides a current and voltage characteristic generation method and device of a transient arc, which can be used in the technical field of power system relay protection, and the method comprises the steps: constructing an arc model through employing an external electromotive force source, an internal resistor, and a plasma with a preset radius, length and transient temperature; generating an energy conservation model and a current model according to the arc model; converting the energy conservation model to obtain a direct current arc temperature model; and utilizing the direct current arc temperature model, the current model and a pre-generated conductivity regression model to generate current and voltage characteristics of the arc. According to the method and device for generating the current and voltage characteristics of the transient arc, the non-transient stable change process of the temperature and the voltage drop of the arc column is obtained, the change process of the arc column is described more accurately, and research on the grounding fault arc resistance of a power distribution network is facilitated.

The invention discloses a fault detection method and system based on lightning protection device performance data, and relates to the technical field of fault detection, and the method comprises the steps: capturing the airflow velocity and airflow pressure deviation of a multi-crack outlet of a lightning protection device under the impact of a high lightning current in real time, and collecting the arc length data of an outlet point of the lightning protection device, and the temperature and instantaneous arc resistance of the thermocouple induction arc column are calculated. According to the method, the normalized airflow energy density and arc energy density features are combined into the joint feature sequence, so that the coupling relationship between the airflow performance and the arc discharge behavior of the lightning protection device can be captured, and the global detection state of slow evolution and instantaneous mutation of the equipment fault is realized; the lightning stroke threat intensity can be independently reflected by defining the dynamic risk index, lightning stroke threat propagation and topological network characteristics are combined in combination with lightning protection device performance detection data, and therefore transmission effect modeling of the lightning stroke dynamic risk is achieved.

The invention relates to the technical field of powder coatings, and provides an insulating powder coating and a preparation method thereof. The insulating powder coating comprises the following raw materials in parts by weight: 82-96 parts of epoxy resin, 5-8 parts of phenolic resin, 12-18 parts of silica powder, 10-15 parts of modified nano aluminum oxide, 3-9 parts of a flame retardant and 0.5-1 part of a flatting agent. Wherein the modified nano aluminum oxide and the silica powder can remarkably improve the breakdown voltage, the arc resistance and the insulativity of the coating; the flame retardant can improve the flame retardance and chemical resistance of the coating, is a halogen-free flame-retardant system, avoids the toxicity problem of the traditional brominated flame retardant, and improves the environmental protection property; in conclusion, the flame-retardant insulating powder coating overcomes the defects of the traditional insulating powder coating in flame retardance, chemical resistance and environmental protection, and has important application value in high-end power electronic equipment.

The utility model belongs to the technical field of furnace roller thermal spraying, and particularly relates to a furnace roller thermal spraying clamping tool which comprises a working table, a mounting plate is mounted at the top of the working table, a supporting column is fixedly mounted at the top of the mounting plate, a lower arc plate is fixedly mounted at the top of the supporting column, an upper arc plate is hinged to the top of the lower arc plate, and the upper arc plate is hinged to the top of the upper arc plate. According to the furnace roller cleaning device, the upper arc plate which is opened and closed is closed to the top of the lower arc plate, then a threaded column is rotated, so that an arc-shaped abutting plate is attached to the outer surface of the furnace roller, the heating wire on the inner wall of the lower arc plate is powered on, the friction assembly is installed in the upper arc plate, and the friction assembly is used for conducting friction cleaning on the outer surface of the furnace roller. The outer surface of the furnace tube is preheated, and the arc-shaped abutting plates rub and clean the outer surface of the furnace roller, so that the effect of preheating and cleaning the outer surface of the furnace roller is achieved.

The invention discloses a molded case circuit breaker on-off process dynamic simulation method based on a heterogeneous simulation system, and relates to the technical field of low-voltage electric appliance design and simulation. Loop current calculated by the first simulation subsystem is transmitted to the second simulation subsystem in real time and used for calculating electromagnetic force for driving a mechanism to move, and contact displacement generated by mechanism movement is immediately fed back to the first subsystem and used for dynamically updating resistance characteristics of an arc model, so that calculation of arc voltage is affected, and the simulation effect is achieved. The arc voltage is directly fed back to the circuit model to determine the current value at the next moment, so that a simulation chain for complete dynamic interaction of the circuit current, the electromagnetic force, the mechanical displacement, the arc resistance, the arc voltage and the circuit current is formed; therefore, the simulation model can reflect the dynamic evolution process of each physical quantity in the real on-off process in a self-consistent manner.

The invention belongs to the technical field of high-voltage cable cells, and provides a copper-aluminum composite material and a preparation method thereof and a cable cell, the material is of a double-layer structure and comprises an inner core and a shell wrapping the outer surface of the inner core, and the shell is a copper strip; the inner core is of a fan-shaped topological structure and comprises a plurality of rare earth composite copper-aluminum alloy matrixes, and raw materials of the rare earth composite copper-aluminum alloy matrixes comprise copper powder, aluminum powder, nanometer aluminum oxide, a cerium source, a magnesium source and nanometer graphene, and the rare earth composite copper-aluminum alloy matrixes are prepared through a distributed mechanical alloying process and multiple times of ball milling. According to the invention, the temperature resistance, creep resistance and arc resistance of the copper-aluminum composite material can be effectively improved, so that the copper-aluminum composite material can bear severe environment performance requirements such as high temperature higher than 150 DEG C when being used as a cable cell for transmitting electric energy, and the requirement of improving the electric energy transmission rate in a high-safety scene of a new energy automobile can be met.

The application provides a simulation method, system and device considering the closing pre-breakdown characteristics of a circuit breaker, and belongs to the technical field of SF6 circuit breaker simulation. The method comprises the following steps: S1, establishing an SF6 circuit breaker controlled element model in simulation software, wherein the controlled element model comprises the relationship between the closing state in the closing process of the circuit breaker and the SF6 gas parameters, and the relationship between the SF6 circuit breaker gap voltage; and the relationship between the arc resistance value in the closing process of the circuit breaker and the arc parameters, the SF6 circuit breaker gap voltage, and the passing current of the SF6 circuit breaker; S2, building an SF6 circuit breaker test circuit simulating a power system and connecting the SF6 circuit breaker controlled element model to the SF6 circuit breaker test circuit; and S3, loading the SF6 gas parameters and the arc parameters, adjusting the real-time gap voltage and the real-time passing current, and performing the system electromagnetic transient process simulation of the SF6 circuit breaker closing pre-breakdown in the SF6 circuit breaker test circuit.

The invention discloses an electric contact material for a high-resistance circuit breaker and a preparation method of the electric contact material, and relates to the technical field of electric contact materials for circuit breakers, the material comprises the following components based on 100 parts by weight of the total weight of a finished product: 92.0-96.8 parts by weight of a pre-alloyed matrix phase which is Ag-30Ni pre-alloyed powder prepared by a gas atomization method; an in-situ carbon reinforcing phase: 1.0 to 2.0 parts by weight of a novolac resin powder as a carbon precursor; the three-phase functional layer phase is 0.1-5.0 parts by weight and is one of tungsten carbide and titanium carbide or a compound of tungsten carbide and titanium carbide according to the weight ratio of 1: 1; the copper infiltration filling phase is electrolytic copper powder or oxygen-free copper liquid; a multi-phase synergistic material system is constructed, all components are complementary, core performance such as arc resistance is balanced and optimized, and the problem that a traditional contact material is short in service life is solved; a precise preparation process chain is integrated, the structure and performance are directionally regulated and controlled, defects are reduced, the anti-loss capacity is improved, the strict requirements of a high-resistance circuit breaker are met, and the service cycle is prolonged.

The utility model belongs to the technical field of gasoline desulfurization, and discloses a device for desulfurization in gasoline preparation, which comprises a reaction box, a gas pipe is fixedly connected to one end of the reaction box close to the top in a penetrating manner, a one-way valve is fixedly connected to a pipe body of the gas pipe, and an oil outlet valve pipe is fixedly connected to the other end of the reaction box close to the bottom in a penetrating manner. A desulfurization part is arranged on the reaction box; t-shaped long plates are stressed and can slide in an arc abutting groove in a limiting mode, then a rotating disc is driven to rotate in a positioning mode in a charging barrel, rotation of the rotating disc can drive two T-shaped blocks to slide in the arc sliding grooves in the opposite directions, and therefore partition plates installed on the two T-shaped blocks can be driven to synchronously conduct limiting translation in the opposite directions in a disc groove; therefore, gasoline or a catalyst in the charging barrels can be discharged without tight separation of the two partition plates, and the two charging barrels can alternately discharge materials intermittently due to back-and-forth swinging of the swing plates, so that the mixing effect and efficiency can be improved subsequently.

The application provides a segmented modeling method of a fuse for a direct current networking system based on arc resistance characteristics, relates to the technical field of common direct current bus system design, and comprises the following steps: calculating real-time arc resistance data of the fuse according to short-circuit voltages and short-circuit currents of two sides of the fuse in a continuously collected short-circuit test process to form an arc resistance curve; intercepting the arc resistance curve between a peak value moment of the short-circuit current and a slope drop moment of the arc resistance curve to obtain an arc resistance curve in an arc striking stage, and intercepting the arc resistance curve between the slope drop moment and a moment when the short-circuit current is zero to obtain an arc resistance curve in an arc burning stage; respectively performing data fitting according to the arc resistance curve in the arc striking stage and the arc resistance curve in the arc burning stage to obtain a segmented arc resistance curve equation; and building a fuse simulation model based on a controlled resistance by taking the arc resistance curve equation as a control signal. The beneficial effect is that the arc resistance curve is divided into two segments and corresponding arc resistance curve equations are designed, the simulation precision is higher, and the method can be better applied to different working conditions.

The invention belongs to the technical field of insulators, and discloses an anti-pollution flashover umbrella skirt structure optimized composite insulator which comprises an insulating core rod and a plurality of umbrella skirt units arranged on the insulating core rod in a sleeving mode, each umbrella skirt unit comprises a main umbrella skirt body and an auxiliary umbrella skirt body, and an annular pollution dredging and flow guiding inclined face is arranged on the upper umbrella face of each main umbrella skirt body. The radial inclination angle of the sewage draining and flow guiding slope is gradually increased in a gradient manner outwards along the radial direction of the umbrella body; the edge of the lower umbrella surface of the main umbrella skirt body is provided with an annular arc-resisting rib; the arc cutting fracture structures cut off the circumferential development path of an electric arc, the annular arc blocking ribs lengthen the creepage path of the electric arc, meanwhile, the arc cutting fractures of the upper and lower adjacent main umbrella skirt bodies are distributed in a staggered mode, axial through of the electric arc is eradicated, the arc extinguishing probability is remarkably improved, and the arc extinguishing effect is improved. And pollution flashover is thoroughly inhibited, and the device is suitable for severe working conditions such as counter-weight pollution and rainstorm.

The invention discloses an AgSnO2 contact material and a preparation method thereof, relates to the technical field of electric contact materials for electric appliances, and solves the problems of high resistivity, poor welding resistance, short arc resistance life, high production cost and the like of contact materials in the prior art. The raw materials of the contact material comprise raw material powder and a dispersing agent, wherein the raw material powder comprises the following components in percentage by mass: 79-90% of Ag powder, 4-10% of Sn powder and 4-10% of alkali metal M powder; the dispersing agent accounts for 0.2-1% of the mass of the raw material powder. According to the preparation method, the AgSnO2 contact material with low resistivity, high welding resistance and long arc-resistant life is obtained through the synergistic effect of methods such as alkali metal doping, freeze drying and oxidation after sintering, the arc-resistant life and other properties of the obtained contact material are improved by 15% or above compared with those of a conventional AgSnO2 material, the process is simple, and the production cost is low.

A method for characterizing single-phase grounding faults in a distribution network that takes into account nonlinear arc resistance includes: constructing a discretized computer simulation model of the arc model; determining fault arc model parameters for the discretized computer simulation model constructed under different conditions based on measured data of arcs generated when a distribution conductor passes through concrete, asphalt pads, gravel patches, or grassy areas when a single-phase grounding fault occurs; inputting the fault arc model parameters into the discretized computer simulation model of the arc model, integrating them with the normal operation model of the distribution network to form a discretized computer simulation model of the distribution network single-phase grounding fault; and performing characterization analysis of the distribution network single-phase grounding fault characteristics including nonlinear arc resistance based on zero-sequence current harmonic extraction and distortion analysis. The present invention implements electromagnetic transient simulation of arc faults occurring on distribution lines on grass, gravel, concrete, asphalt roads, or trees, meeting the needs of arc fault detection for single-phase grounding faults in distribution networks.

The invention discloses an arc resistance simulation verification method for a field suppression switch structure and operating characteristics, an arc resistance simulation verification device for the field suppression switch structure and operating characteristics, arc resistance simulation verification equipment and a computer readable storage medium. The method comprises the following steps: firstly, establishing a three-dimensional geometric model comprising an arc extinguish chamber, a contact system and an operating mechanism; then, constructing a mechanical structure dynamic simulation model to obtain the motion characteristics of the moving contact, and finally, establishing a multi-physical field coupling mathematical model based on a fluid dynamic equation, an electromagnetic field equation and a heat transfer equation to realize numerical simulation of the arc breaking process of the field suppression switch. According to the method, the flowing, electromagnetic and heat transfer characteristics of the arc are comprehensively considered, the whole process from generation to extinguishing of the arc can be completely simulated, and an effective simulation analysis means is provided for design optimization, performance evaluation and breaking capacity verification of the field suppression switch.

The application relates to a judgment method and device for DC arc resistance of an arc extinguishing chamber and a computer device. The method comprises the following steps: building an arc burning working condition simulation environment of the arc extinguishing chamber in a pre-constructed high-speed switch geometric model, calculating a gas flow field in the arc extinguishing chamber based on a real gas model of an arc magnetic fluid model, calculating distribution structures of multiple physical fields of the arc extinguishing chamber in a preset time under the arc burning working condition based on a gas flow field control equation group, a turbulence model and the gas flow field in the arc magnetic fluid model, calculating an ablation mass of the arc extinguishing chamber in the preset time under the arc burning working condition based on a radiation model and an ablation model in the arc magnetic fluid model, and evaluating the resistance characteristics of the arc extinguishing chamber based on the distribution structures of the multiple physical fields and the ablation mass of the arc extinguishing chamber in the preset time in the arc burning process. The evaluation of the long-time DC arc resistance performance of the arc extinguishing chamber can be realized based on the distribution structures of the multiple physical fields and the ablation mass of the arc extinguishing chamber in the preset time.

According to the circuit breaker breaking arc simulation system and method, a near-zone circuit simulation module is used for constructing and operating a circuit breaker external near-zone fault circuit model, outputting an arc current value and receiving an arc resistance value; the breaking arc simulation module is used for constructing and operating an arc magnetofluid model, outputting a gas chamber counterforce and receiving a contact movement speed; the spring operating mechanism simulation module is used for constructing and operating a circuit breaker operating mechanism multi-body dynamic model, outputting contact movement speed and receiving air chamber counterforce; the data relay and processing node module is used for receiving data information from the near-zone circuit simulation module, the breaking arc simulation module and the spring operating mechanism simulation module, analyzing and classifying the data information and then sending the data information to the corresponding simulation modules; the UDP communication module is used for realizing data transmission between each simulation module and the data relay and processing node; and the automatic running script module is used for controlling initialization, running, parameter updating and iterative loop of each simulation module.

The application provides an insulating tube for high-voltage cable protection and a preparation method thereof. The insulating tube is composed of an outer tube, an inner tube and a transition layer. The raw material for preparing the outer tube comprises a base resin, a carrier resin, a flame retardant and a slip agent, wherein the flame retardant comprises low-melting-point glass fiber, a phosphorus-nitrogen intumescent flame retardant and a silane coupling agent; the raw material for the inner tube comprises a main body resin and a solubilizing agent; and the raw material for the transition layer comprises soluble fiber raw material, nano-clay and a dispersing agent. Through a composite flame-retardant system and a multi-layer structure design, the application significantly improves the arc resistance, the flame retardant grade and the interlayer bonding force of the insulating tube, solves the technical problems that the traditional insulating tube is prone to breakdown and peeling in a high-voltage environment, and is suitable for long-term safe protection of high-voltage cables.

The invention relates to a method and a device for establishing a single-phase earth fault arc model. The method comprises the following steps: collecting arc data and load data in an arc stage, and establishing an arc model according to the arc data and the load data: for an arc starting stage, obtaining arc starting resistance according to arc current, arc voltage, load current and load voltage in the arc starting stage; for the steady-state arcing stage, arcing resistance is obtained according to the arc current, the arc voltage, the load current and the load voltage of the steady-state arcing stage; and for the arc quenching stage, obtaining the arc quenching resistance according to the arc current, the arc voltage, the load current and the load voltage in the arc quenching stage. According to the method, the arc models are established in stages from the arc starting stage, the steady-state arcing stage and the arc extinguishing stage, so that the arc model of each arc stage better conforms to the arc characteristics of each stage, and the actual single-phase earth fault arc can be better simulated.

The invention discloses a material composition for a high-pressure-resistant product and a preparation method of the material composition. The composite material comprises the following raw materials in percentage by mass: 40-55% of PPS; 25% to 35% of PPA; 10 to 20% of reinforcing fiber; 5-8% of a flame retardant synergist; 0.5-2% of a coupling agent; 0.3 to 1% of an antioxidant; and 3-5% of an inorganic filler. In the preparation process, a gradient temperature control melt extrusion process is adopted, and a fiber directional distribution and interface chemical bonding technology is combined, so that the material has high rigidity, low shrinkage rate and excellent arc resistance. The obtained material can still keep stable mechanical properties and insulation characteristics in a high-humidity and high-pressure environment, is suitable for the fields of high-voltage connectors of new energy automobiles, electronic and electric appliance parts and the like with strict requirements on dimensional accuracy and voltage resistance grade, and solves the technical contradiction that high CTI value of PPA is difficult to cooperate with high rigidity and dimensional stability of PPS.

The present invention relates to a power equipment room having a ventilation device, and more particularly, to a power equipment room having a ventilation device applied to a metal distribution board having arc resistance. According to the power equipment room with the ventilation device, the ventilation device is arranged in the circuit breaker room, the ventilation device is opened in a normal state, so that the ventilation device can serve as a ventilation opening, and when an arc accident occurs, the ventilation device is closed, so that safety accidents can be prevented.

The utility model discloses a transmission mechanism of a magnetic latching relay, which comprises a moving armature assembly and a moving contact assembly, one side of the moving armature assembly is provided with a hinged support, a moving contact position of the moving contact assembly is provided with an elastic sheet support, the elastic sheet support is provided with an inclined elastic sheet, and the elastic sheet is provided with a movable contact. The moving armature assembly is connected with the moving contact assembly through a transmission part, the transmission part is pivoted on a relay base, one end of the transmission part is provided with a first transmission arm which is obliquely arranged and is connected with a hinged support of the moving armature assembly, and the other end of the transmission part is provided with a second transmission arm which is obliquely arranged and is abutted against the elastic sheet; the inclined elastic sheet can increase the distance between the moving contact and the static contact, and the arc resistance of the magnetic latching relay is improved.