421results about How to "Improve lightning protection effect" patented technology

The invention discloses a detailed terrain data-based transmission line failure-shielding and lightning-protection performance evaluation method. The method comprises the following steps of: acquiring statistical lightning data of a line corridor in a specified time period by a lightning parameter statistical method by adopting line basic information, line geographic information, line structural characteristics and line insulation characteristics; scanning a three-dimensional coordinate of a transmission line corridor by using geographic information system (GIS) software; determining the landscape along a line and a ground angle according to the three-dimensional coordinate in the direction vertical to the line corridor; determining wire-to-ground height variation caused by surface undulation according to the three-dimensional coordinate in the direction along the line, and acquiring detailed terrain data along the line by three-dimensional GIS scanning; calculating the shielding failure trip-out rate of each base tower according to the detailed terrain data extracted based on the GIS scanning; and acquiring real line failure-shielding and lightning-protection evaluation data in the specified time period by comparing a design value, a specified value or an operation experience value of the line failure shielding trip-out rate with a reference value of the line failure shielding trip-out rate. Therefore, the line failure-shielding and lightning-protection performance evaluation is realized.

The invention discloses an over-voltage over-current protector of electronic and electric equipment. The over-voltage over-current protector of the electronic and electric equipment comprises a power surge protective device SPD I, a surge voltage divider and a power frequency current protector, two ends of the power surge protective device SPDI are respectively connected with a live wire and a null line after a power supply distribution board access port and before a protected equipment port, the surge voltage divider is composed of an electric reactor A, a power surge protective device SPD II and an electric reactor B in a series mode, the electric reactor A at one end of the surge voltage divider is arranged on a live wire after the power surge protective device SPD I, the electric reactor B at the other end is arranged on a null line after the power surge protective device SPD I, and the power frequency current protector is composed of a PTC positive temperature coefficient thermistor, an NTC negative temperature coefficient thermistor and a TVS tube. The over-voltage over-current protector of the electronic and electric equipment has surge over-voltage limit and surge residual voltage division protection functions and power frequency over-voltage and over-current protection functions, enables the equipment fault rate to be reduced and enables the equipment aging speed to be lowered.

The invention discloses a reinforced type all-dielectric and rodent-resistant cable and a manufacturing process of the reinforced type all-dielectric and rodent-resistant cable, and relates to the technical field of communication cables. The reinforced type all-dielectric and rodent-resistant cable comprises multiple optical fibers, fiber paste, a loose casing pipe, a center reinforcement piece, a cable core water-resistant compound, an inner sheath, multiple rod-shaped FRPs 7 and an outer sheath, wherein the multiple rod-shaped FRPs 7 are arranged between the inner sheath and the outer sheath; the multiple optical fibers are arranged inside the inner sheath; the loose casing pipe is arranged outside the optical fibers; the position between the optical fibers and the loose casing pipe is filled with the fiber paste; the position between the loose casing pipe and the inner sheath is filled with the cable core water-resistant compound; the center reinforcement piece is arranged in the center of the optical fibers. According to the reinforced type all-dielectric and rodent-resistant cable and the manufacturing process of the reinforced type all-dielectric and rodent-resistant cable, the weight of FRP sheathed rodent-resistant cables is reduced greatly, the difficulty of laying construction is not added under the condition that the cables have the good rodent-resistant effect, and the solution is provided for optical communications at areas with serious damage caused by rodents, such as mountainous areas and sewer lines of cities.

The invention discloses a base station lightning protection system, comprising a grounding bar, a machine room main distribution, a lightning protector, base station assorted equipment, wherein the grounding bar is connected with ground wires of all equipment in a machine room and is used for carrying out grounding aggregation on the ground wires of all the equipment; the machine room main distribution is connected with the grounding bar by ground wires and is used for providing an alternating current power source for all the equipment in the machine room; the lightning protector is connectedwith the grounding bar by a PE end and is used for bleeding lightning current led into the machine room; the base station assorted equipment is connected with the grounding bar by the ground wires; the connecting point of the lighting protector and the grounding bar is positioned at the position on the grounding bar, closest to a grounding network; and the connection point of the machine room maindistribution and the grounding bar is positioned on the PE end, closest to the lightning protector, on the grounding bar. The grounding network corresponding to all the equipment in the machine roomhas the same electrical potential, thus loosening the requirements to the resistance value of the grounding network of a base station, simultaneously also improving the lightning protection capabilityof the whole base station system to a great extent and effectively guaranteeing the safety of all the equipment in the machine room of the base station.

The invention discloses an intelligent insulation line lightning protection on-line monitoring device and method. The intelligent insulation line lightning protection on-line monitoring device comprises a CPU module, the input end of the CPU module is connected with a sampling module, an environment temperature detection module and a power supply module, the sampling module is connected with a current transformer and a voltage transformer of a lightning arrester, and the environment temperature detection module is connected with a temperature sensor of the lightning arrester; the CPU module isfurther connected with a communication module and is in communication with the communication module, and the communication module is in communication with a system main station; the wire of a power distribution line is supported on a cross arm through an insulator string; the lightning arrester comprises a support clamp, a wiring spherical electrode, a grounding spherical electrode and an adjustable fixed support; and the support clamp is clamped to bear the wiring spherical electrode, the wiring spherical electrode is conducted with a conducting wire through the support clamp, and the grounding spherical electrode is supported on the cross arm through the adjustable fixed support and is ground connected. According to the device, the insulators are prevented from being attacked by lightning, data remote transmission is carried out on the lightning arrester leakage current and resistive current component and action times, and the working efficiency is high.

The invention provides a lightning protection device, a lightning protection combination, a lightning protection cabinet and a protection method for applying the lightning protection cabinet to a track circuit. The lightning protection device is characterized in that nonlinear elements (101) are connected to the primary or the secondary of an isolation transformer (102) in parallel, or the nonlinear elements (101) are connected to the primary and the secondary of the isolation transformer (102) in parallel respectively, two leads of a primary coil of the isolation transformer (102) are used as the two input ends of the lightning protection device, two leads of a secondary coil of the isolation transformer (102) are used as the two output ends of the lightning protection device, and an iron core and a shielding shell of the isolation transformer are used as the ground wire end of the lightning protection device. The isolation transformer is used as the main lightning protection component, the structure is simple, the lightning protection effect is good, and the defects in the prior art are overcome.

The invention relates to a lightning-protection earthing device, in particular to a double-shielding lightning rod and an earthing device, in particular to a lightning-protection earthing device suitable for fields, such as communication, electric power or traffic and the like. The lightning-protection earthing device belongs to the technical field of lightning-protection earthing. The double-shielding lightning rod and earthing device comprises a lightning rod tube, one end part of the lighting rod tube is provided with an insulated post fixedly connected, and the insulated post is provided with a calabash ball provided with a conducted ball tip; the conducted ball tip is provided with an anti-lightning shielding cable of which one end is connected with the conducted ball tip, and the other end passes through the calabash ball and the insulated post to extend into the lightning rod tube; the anti-lightning shielding cable is distributed along the length of the lightning rod tube; and the other end of the anti-lightning shielding cable, which is correspondingly connected with the conducted ball tip, is connected with a grounding electrode. The earthing device is compact and simple in structure, has good anti-lightning effect, can effectively attenuate thunder and lightning electromagnetic pulse, is convenient to install and use and is safe and reliable.

The invention relates to a method for improving the lightning protection capacity of a super or ultra high-voltage transmission line. Under the condition of no changing the original line pole tower and conducting wire type, two lightning protection line brackets are arranged on a middle-phase cross pole of the one-tower double-circuit super or ultra-high-voltage pole tower additionally, and two lightning protection lines are arranged on the brackets along the line additionally. Compared with the existing super or ultra high-voltage transmission line, the invention can improve the lightning protection capacity of the super or ultra high-voltage transmission line, and the cost of the newly added lightning protection line brackets and the lightning protection lines is only about 4 percent of the original total cost.

The invention discloses a radar antenna housing. In the radar antenna housing, a spherical segment housing body which has a honeycomb sandwich structure is adopted; the radar antenna housing is formed by splicing modules which are made of glass fiber reinforced plastic and paper honeycombs; thus the wave penetrating performance and the mechanical strength of the glass fiber reinforced plastic and the paper honeycombs are fully utilized, and the effects of sheltering rain, snow, hail, strong light and the like are achieved without the influence on the normal use of a radar antenna. In addition, a lightning rod is arranged beside the housing body, so the possibility of lightning stroke can be greatly reduced when the radar antenna housing is used on a tall building so as to fulfill the aim of safe use.

The invention discloses a system and method for measuring the intensity of a long air gap lightning stroke discharging electric field, and relates to the technical field of electric systems. The system and method are used for acquiring high-precision electric field intensity of the streamer, guidance and tail leap conversion processes, improving the deep degree of discharging physical mechanism research under long air gap lightning impulses, and finally improving the lightning preventing capacity of the electric systems. The system for measuring the intensity of the long air gap lightning stroke discharging electric field comprises an impulse voltage generator, a capacitive voltage divider, a measuring resistor, a plate electrode, a bar electrode located above the plate electrode, a spectrograph, an ICCD camera and an oscilloscope. The measuring system in the technical scheme is applied to the method for measuring the intensity of the long air gap lightning stroke discharging electric field. The system and method for measuring the intensity of the long air gap lightning stroke discharging electric field are used for study of lightning defense of the electric systems.

The signal lightning protection includes lightning protection device formed from at least more than one transient killer diode and placed between two signal lines and ground, and is characterized by that it also includes common-mode lightning protection circuit formed from at least more than one voltage-sensitive resistor and gaseous discharge tube or their combination and placed between two signal lines and between two signal lines and ground, so that said ivnention possesses double protection, and can effectively raise lightning protection performance of the equipment.

The invention discloses a distribution line lightning damage risk assessment method based on regionalization. The distribution line lightning damage risk assessment method based on regionalization comprises the steps of determining a region, collecting data, assessing a geographical environment, assessing a lightning withstand level, analyzing lightning damage risks, and regarding a pole tower having topographic risk assessment result and overvoltage risk assessment result features simultaneously as a key protection pole tower. The distribution line lightning damage risk assessment method can realize regional lightning damage prevention and treatment, and provides scientific, quantitative and effective basis for intra-regional power distribution network lightning protection governance; by implementing the distribution line lightning damage risk assessment method, limited fund can be invested to key lines and key sections (dangerous lines, dangerous sections), so as to achieve the most economical investment, obtain the optimum lightning protection effect, improve the overall lightning protection level of the intra-regional power distribution lines, and enhance power supply reliability; and the distribution line lightning damage risk assessment method can be used for assessing lightning damage risks of the power distribution line at the early stage of construction, provides necessary technical support for the design unit, and makes the optimum line erection design scheme.

The invention relates to an alternating current electric transmission line lightning flashover restriction method and device. The method includes the steps of current steering, voltage limiting and arc blowing-out. The current steering includes the steps of providing a current discharge channel for power frequency short-circuit current through a parallel gap, wherein the parallel gap is mounted on both ends of an insulator, the breakdown strength of the parallel gap is lower than that of the insulator, and lightning current flows through the parallel gap rather than passing through the insulator when the parallel gap is broken down by lightning. The voltage limiting includes the steps of connecting a non-linear energy absorbing assembly in series with the parallel gap and limiting over-voltage at both ends of the insulator to prevent the insulator from being damaged by lightning flashover, wherein the non-linear energy absorbing assembly is used for absorbing lightning current energy on the basis of current steering. The arc blowing-out includes the steps of treating continuous combustion caused by arc produced in the parallel gap when the power frequency short-circuit current continues to flow through the parallel gap after lightning current passes to prevent tripping of a circuit breaker. The alternating current electric transmission line lightning flashover restriction device is composed of the parallel gap, electrodes, the non-linear energy absorbing assembly and a special-shaped connecting unit which are assembled and connected with one another and is simple in structure, light in weight and small in size.

The invention belongs to the technical field of power equipment, and especially relates to a novel multifunctional power electrical transformer in order to solve the problems of simple design structure, single function, and low safety performance of a power transformer. The novel multifunctional power electrical transformer comprises a base, wherein four corners of an outer wall of the top of thebase are all welded with sleeves, and an inner wall of the each sleeve is slidingly connected with a piston, an outer wall of the top of the piston is welded with a supporting rod, a damping spring sleeves an outer wall of the supporting rod, a shell is fixed to an outer wall of the top of the supporting rod through a screw, a mounting platform is fixed to an inner wall of the bottom of the shellthrough a screw, and a heat dissipation plate is fixed to an outer wall of the bottom of the mounting platform through a screw. The novel multifunctional power electrical transformer of the inventionhas the beneficial effects of good heat dissipation effect, capacity for preventing burnout of components inside the shell caused by excessively high temperature inside the shell, capacity for significantly prolonging a service life of the transformer, high intelligence degree, capacity for reducing property loss caused by firing of the transformer, high safety performance, and powerful functions.

The invention belongs to the technical field of lightning protection, and provides a lightning protection circuit. The lightning protection circuit comprises a thunder and lightning absorption and isolation circuit connected in series to a power supply line of a device to be protected; the thunder and lightning absorption and isolation circuit comprises a thunder and lightning absorption circuit for absorbing lightning current and a thunder and lightning isolation circuit for performing frequency-selecting and filtering to the current passing therethrough, so that a power frequency signal or a carrier signal passes through to prevent transmission of lightning current, thus playing a role in lightning protection. Compared with the prior art, the lightning protection circuit distributes a shunt proportion of the lightning current without relying on a resistance value of a grounding grid and characteristic impedance of the device to be protected, thus being good in lightning protection effect. In addition, a first surge protection circuit and a second surge protection circuit can be added to further strengthen the lightning protection effect and the requirement of the resistance value of the grounding grid can be greatly reduced, namely the grounding grid with high resistance value can be used, and thereby construction cost of the grounding grid is greatly reduced, and construction period is shortened.

The invention provides a lightning protection seat and a vehicle with the lightning protection seat. The lightning protection seat comprises a mounting boom which can be arranged in a cab of the vehicle and can be connected with a roof and a floor of the vehicle respectively. A seat frame connected to the mounting boom, wherein at least two portions of the seat frame are slidable relative to eachother; A lightning protection assembly connected with a seat frame, that lightning protection assembly comprises a plurality of lightning protection members, and the plurality of lightning protectionmembers are cooperated to carry out multiple energy absorption deformation when the vehicle is impacted; A seat cover, the seat cover being arranged on the seat frame; a seat belt assembly, which is attached to the seat frame to secure the occupant. The lightning protection seat of the invention can absorb energy and deform the explosive shock wave for many times through the cooperation of a plurality of lightning protection parts, prolongs the cushioning time of the lightning protection seat to the explosive shock wave, enables the human body to bear greater impact acceleration, and guarantees the safety of the human body.

The invention relates to the technical field of lightning protection devices, and discloses a lightning protection system for a wind turbine blade. The lightning protection system comprises a blade body lightning arresting unit, a blade tip lightning arresting unit and a lead wire; the blade body lightning arresting unit comprises a blade body lightning arrester and a blade body lightning arresterbase; threaded holes perpendicular to the upper end surface and the lower end surface are correspondingly formed in the upper end surface and the lower end surface of the blade body lightning arrester base; threaded columns matched with the threaded holes are arranged at the lower end of the blade body lightning arrester; the blade tip lightning arresting unit comprises a blade tip lightning arrester and a blade tip lightning arrester base; a clamping groove is formed in the end part of the blade tip lightning arrester; a clamping block matched with the clamping groove is arranged at one endof the blade tip lightning arrester base; threaded holes are formed in the clamping block; and counterbores paired with the threaded holes in the clamping block are formed in the clamping groove. In the scheme, the blade body lightning arresting unit and the blade tip lightning arresting unit are separately connected in a matching manner, so that the surface-surface fit of the lightning arrestersand the lightning arrester bases is realized, the electrical contact area is sufficient, the lightning protection system is stable and reliable, and the phenomenon of sparking is prevented, so that abetter lightning protection effect is achieved.

The invention discloses a lightning arrester of a blade of a wind-driven generator, and belongs to novel-material lightning arresters of blades of wind-driven generators. The lightning arrester of the blade of the wind-driven generator comprises the blade of the wind-driven generator, and is characterized in that a lightning arrester body of the blade is arranged at a tip of the blade of the wind-driven generator, aluminum, magnesium and copper alloy pieces adhered with one another via epoxy resin are subjected to die-casting to form the lightning arrester body of the blade, the lightning arrester body of the blade is connected with cables by cable fixing bolts, and the cables are connected with middle receivers and are connected with a main cable of a lightning protection device connected onto a support of the wind-driven generator. The lightning arrester of the blade has the advantages that the lightning arrester is excellent in conductivity, good in corrosion resistance and lightning protection effect and long in service life, and is a novel critical product for guaranteeing the blade of the wind-driven generator against lightning stroke.

The invention discloses a lightning protection column type insulator. The lightning protection column type insulator comprises an upper fitting, a lower fitting and a shell, wherein the upper fitting, the shell and the lower fitting are connected sequentially and fixedly to form a closed cavity. A resistor disc and a resistor ring are arranged in the cavity sequentially from top to bottom. Discharging electrodes are arranged in the resistor ring. A spring is arranged between the upper fitting and the resistor disc in the cavity. A rubber umbrella skirt is fixed to the outer wall of the shell. The lightning protection column type insulator is characterized in that the shell is formed by compounding an inner insulation layer, a middle carbon fiber reinforced layer and an outer insulation layer, a high temperature resistant ceramic tube in clearance fit with the inner insulation layer of the shell is arranged in the cavity, the resistor disc and the resistor ring are annularly arranged in the high temperature resistant ceramic tube, the discharging electrodes are arranged in the resistor ring in pair in the axial direction, a one-way exhaust valve communicated with the atmosphere is arranged in the lower fitting, and the discharging ends of the discharging electrodes are arc. The lightning protection column type insulator has the advantages of being reasonable in structure, high in strength and reliability, good in lightning protection effect, long in service life, safe and the like.

The invention relates to a flame-retardant and fire-retardant cable with high performance. The flame-retardant and fire-retardant cable comprises a cable core, reinforcing pieces and a protection layer, wherein the protection layer wraps outside the cable core and the reinforcing pieces; the protection layer is composed of water-blocking tape, a ceramic fiber tape and an outer protection sleeve; the outer protection sleeve is the outermost layer of the protection layer. According to the flame-retardant and fire-retardant cable with high performance, micro beam tubes are longitudinally wrapped by ceramic fiber high-performance flame-retardant material, two flame-retardant inner protection sleeves made of non-metal material are embedded in the outer side of the wrapped tape in an extruding manner, and after a fluorophlogopite tape is longitudinally wrapped, the flame-retardant outer protection sleeve is also formed in an extruding manner; and therefore, high density capacity of the optical fiber cable is improved, and meanwhile the excellent flame-retardant of the cable is ensured by multiple measures such as the dual-layer flame-retardant protection sleeves, the ceramic fiber tape, the mica tape and the like.

The invention discloses a DC charging pile with fault clearing function, A plug terminal is telescopically arranged on the charging gun head, A through hole is axially formed in the center of the cylinder of the plug end, a plurality of first channels are arranged on the periphery of the through hole, a pair of half cross-sectional bodies are movably arranged in the through hole, a plurality of second channels corresponding to the first channels are arranged on the periphery of the half cross-sectional bodies, and the first channels and the second channels are butted to form a conductive plughole for inserting a charging pin interface of an automobile. A half-conical cavity is axially formed in the cross section of the half-section body, a conical cylinder is telescopically arranged in the semi-conical cavity on the left and right sides, Semi-annular grooves are respectively arranged on the side walls of the left and right semi-conical cavities, an annular bump is correspondingly protruded from the outer periphery of the conical cylinder, the annular bump is confined in the semi-annular groove, the width of the semi-annular groove is larger than the width of the annular bump, andthe diameter is larger than the diameter of the annular bump. The invention solves the technical problem that the fault of the DC charging pile is not removed in time.

The invention relates to a toothed disc type wind power generation lightning arrester. The lightning arrester is characterized in that the lightning arrester comprises an external toothed disc and an internal toothed disc positioned in the center of the external toothed disc; the external toothed disc and the internal toothed disc are oppositely provided with sharp teeth which can achieve a point discharge effect toward the side of the moving gap; the center of the internal toothed disc is provided with a hole through which a main shaft of a fan passes; one toothed disc is fixed on a wheel boss of the fan and synchronously rotates along with the wheel boss, and the toothed disc fixed on the wheel boss is electrically connected with a lightning receiving needle fixed on a fan blade; and the other toothed disc is fixed at the front end of a cabin shell and directly connected with a ground wire. By the matching of the sharp teeth of the moving gap of the internal toothed disc and the external toothed disc, the lightning guided by the lightning receiving needle fixed on the fan blade forms the point discharge phenomenon in the sharp tooth structure between the internal toothed disc and the external toothed disc and is quickly and directly discharged to the ground, so that the electric generator or other units avoid lightning surge damage to the maximum extent.

The invention relates to a V-shaped multilayer lightningproof-structure armored vehicle with a central spine beam transmission structure, and belongs to the technical field of lightningproof armored vehicles. The V-shaped multilayer lightningproof-structure armored vehicle comprises a vehicle body, an engine, a gearbox and a drive chain assembly, wherein the vehicle body is made of boards, the engine is fixed on the vehicle body, the gearbox is connected to the engine, the drive chain assembly is connected to the engine, the vehicle body is provided with a central line, a top, a side part and a bottom, the bottom of the vehicle body is a trapezoid armored plate, the vehicle body is integrally welded, and the trapezoid armored plate of the bottom of the vehicle body is connected with a chassis. The V-shaped multilayer lightningproof-structure armored vehicle is characterized in that the chassis connected with the bottom of the vehicle body is formed by a front-back through central spine beam transmission structure and a swinging half shaft in an independent suspension manner, the central spine beam is a high-strength metal round pipe, a transmission mechanism is arranged in the round pipe, a jointed V-shaped protection board is arranged below the front-back through central spine beam transmission structure, and the jointed V-shaped protection board is symmetric about two sides of the longitudinal central line of the vehicle body and is connected with the bottom of the integrally welded vehicle body.

A vent stringer 20 is formed by a pair of ribs 21 rising in the direction perpendicular to an inner surface 11a of a wing panel 11, and a cover 22 provided in the tip end portions of the ribs 21. With rivets 23 unexposed to an outer surface 1 lb of the wing panel 11, a spark is prevented from occurring in a fuel tank 30, which is provided in a main wing 10, through the rivet 23 at the time of a lightning strike. Formed by being machined integrally with the wing panel 11, the rib 21 is formed with high accuracy so as to match the curved shape of the wing panel 11. The cover 22 has only to be formed by curving a strap member so as to match the shapes of the wing panel 11 and the ribs 21.

A vent stringer 20 is formed by a pair of ribs 21 rising in the direction perpendicular to an inner surface 11a of a wing panel 11, and a cover 22 provided in the tip end portions of the ribs 21. With rivets 23 unexposed to an outer surface 11b of the wing panel 11, a spark is prevented from occurring in a fuel tank 30, which is provided in a main wing 10, through the rivet 23 at the time of a lightning strike. Formed by being machined integrally with the wing panel 11, the rib 21 is formed with high accuracy so as to match the curved shape of the wing panel 11. The cover 22 has only to be formed by curving a strap member so as to match the shapes of the wing panel 11 and the ribs 21.

The invention relates to an Ethernet port circuit and provides an external Ethernet port lightning protection circuit, an external lightning protection device and an internal Ethernet port lightning circuit which are used for improving the lightning surge preventing capability of the traditional Ethernet port. A primary isolated transformer is added on the basis of the traditional first-stage isolated transformer to form a double isolated protection; the Ethernet port lightning protection device is added on the external Ethernet port lightning protection circuit under the condition without making any change on the traditional network equipment, so that the lightning preventing capability of the network equipment is remarkably improved, an extra grounded wire is free from being arranged and the deployment is convenient. The internal Ethernet port lightning circuit adopts the compatible design, and an RJ45 with a transformer port is used to doubly improve the lightning preventing capability while not adding the area of a printed circuit board when the lightning preventing protection needs enhancing.

The invention discloses a semi-automatic block railway steel rail breaking monitoring system and method. The monitoring system is provided with at least one monitoring section, and each monitoring section is provided with monitoring equipment. Each piece of monitoring equipment comprises a direct current power source, a monitoring host, an information acquisition module and a data transmission module, wherein the monitoring host is connected with the direct current power source, the information acquisition module and the data transmission module; and the information acquisition module comprises a plurality of steel rail direct current resistors, a plurality of steel rail short-circuit wires, a circuit protection voltage dependent resistor, a low-frequency choking coil and an adjusting current limit resistor. Each monitoring section is divided into a plurality of segments, and two steel rails comprise the first steel rail and the second steel rail. The segments of the first steel rail and the second steel rail are each provided with the corresponding steel rail direct current resistor, and each segment of the first steel rail is connected with the corresponding segment of the secondsteel rail through a short-circuit resistor. The semi-automatic block railway steel rail breaking monitoring system and method provided by the invention can be used for monitoring steel rail breakingand ensuring the safety of railway traffic.

The invention belongs to the design field of lightning protection circuits, and provides a lightning protection circuit of a direct-current system. The circuit comprises a primary lightning protection circuit which is in parallel connection with to-be-protected direct-current equipment in the direct-current system. A lightning current suppression circuit is in parallel connection between the primary lightning protection circuit and the to-be-protected direct-current equipment. When lightning currents are introduced through a power wire, and a part of lightning currents pass a primary lightning protection discharging place. Then, transient high impedance is formed as for remained lightning current waveforms by the lightning current suppression circuit, so that the primary lightning protection circuit can be connected quickly to discharge more lightning current energy, the lightning currents are prevented from spreading along the power wire and lightning protection effect is optimized. Meanwhile, discharging distribution of the lightning currents no longer only depends on resistance of a grounding grid and characteristic impedance of the to-be-protected equipment, so that resistance requirements on the grounding grid can be relaxed, construction and maintenance costs of the grounding grid are remarkably reduced and construction period of the grounding grid is shortened.

The invention discloses a system and a method for measuring lightning discharge electron density in a long air gap and relates to the technical field of an electric power system. The measuring system and method are used for acquiring the electron density of a high-precision pouring, guidance and tail-jump conversion process, promoting the degree of research on a discharge physical mechanism under long air gap lightning surge and finally increasing the lightning protection capacity of the electric power system. The measuring system comprises an impulse voltage generator, a capacitive voltage divider, a measuring resistor, a plate electrode, a rod electrode, a spectrograph, an ICCD camera and an oscilloscope, wherein the rod electrode is located above the plate electrode. The measuring method is applied to the measuring system provided by the technical scheme. The measuring system and method provided by the invention are applied to the research on lightening prevention of the electric power system.