368 results about "Breaking capacity" patented technology

The utility model relates to the technical field of circuit breaker structures, in particular to a rotating shaft structure of a double-breakpoint molded case circuit breaker, which is characterized in that a rotating shaft main body is of an integral structure design, a contact groove is formed in the rotating shaft main body along the radial direction, the middle part of a moving contact is inserted into the contact groove, and two ends of the moving contact penetrate out along an opening of the contact groove; the static spring shaft and the moving spring shaft are used for being in butt joint with the static contact, the static spring shaft and the moving spring shaft are located on the two sides of the moving contact respectively, the two ends of the contact spring are connected to the static spring shaft and the moving spring shaft respectively, and the moving spring shaft is pulled through elastic tension of the contact spring so that the two sides of the moving contact can abut against the inner side wall of the contact groove respectively. Due to the integral structure design of the rotating shaft main body, the three-phase synchronism of the molded case circuit breaker is consistent, the limit breaking capacity and the operation breaking capacity of the circuit breaker are greatly improved, the safety and the reliability of the circuit breaker in operation are improved, and the electrical life of the circuit breaker is prolonged.

The invention relates to a method, a device and equipment for detecting the breaking capacity of a circuit breaker, a medium and a program product. The method comprises the following steps: acquiring a simulation model of a target circuit breaker, current breaking current and current arcing time; according to the simulation model, the current breaking current and the current arcing time, analog simulation is conducted on the working process of the target circuit breaker, and working temperature information of the target circuit breaker is obtained, the working temperature information represents a working temperature change state of the target circuit breaker in an arc combustion process and a medium recovery process; and detecting the breaking capacity of the target circuit breaker according to the working temperature information. By adopting the method, the detection accuracy of the breaking capacity of the circuit breaker can be improved.

The invention relates to a pole-mounted circuit breaker monitoring method and system, electronic equipment and a medium. The method comprises the following steps: acquiring a voltage recovery waveform characteristic and a mechanical vibration characteristic during operation of a vacuum arc-extinguishing chamber, and performing timestamp alignment; calculating a contact gap conductive channel risk value based on the aligned waveform characteristics; generating breaking capacity attenuation trend characteristics by combining the historical breaking current peak value, the breaking times and the risk value; calculating the remaining service life according to the trend characteristics, and synchronously obtaining a fault probability value according to the conductive channel risk value; and finally, according to the residual service life and the fault probability value, determining a maintenance early warning level and outputting a maintenance early warning signal. Therefore, according to the method, the risk of the conductive channel is evaluated through fusion of the operation waveform and the mechanical signal, and the breaking capacity attenuation trend is extrapolated along the historical breaking data, so that online evaluation and advanced early warning of the health state of the pole-mounted circuit breaker are realized, and the operation reliability and the operation and maintenance efficiency of the key node of the power distribution network are improved.

The present application relates to a high-breaking-power fuse, comprising a protective tube; a contact blade, which is sealed and arranged on both ends of the protective tube, and is used to form an arc-extinguishing cavity on the inner side of the protective tube; a fuse, which is arranged in the arc-extinguishing cavity; a conductive connecting piece, which is arranged at the disconnection point between the fuse and the circuit where the contact blade is located; an overload installation box, which is arranged in the arc-extinguishing cavity, and the overload installation box is provided with a mounting cavity and a connecting hole; a connecting rod, one end of which is arranged in the mounting cavity, and the other end slides in and out of the connecting hole, and an arc-extinguishing filling area connected to the connecting hole is formed between the mounting cavity and the connecting rod; a connecting solder, which is arranged between the fuse and the end of the connecting rod outside the mounting cavity, and is used to conduct the disconnection point between the fuse and the circuit where the contact blade is located; a breaking spring, which is connected to the connecting rod and is used to retract the connecting rod into the mounting cavity; and an arc-extinguishing medium, which is filled with overpressure and arranged in the arc-extinguishing cavity. The present application has the effect of improving the arc-extinguishing performance of the fuse.

The invention relates to a fuse and electric equipment. The fuse comprises a shell, an electric connection unit, an action unit and an excitation unit. The shell is provided with a first cavity and a second cavity, and a communicating hole is formed in the cavity wall of the first cavity so that the first cavity can communicate with the second cavity. The electric connection unit is mounted on the shell and comprises a connection bar and a melt which are connected in parallel; the action unit comprises a first breaker movably installed in the first chamber and a second breaker movably installed in the second chamber. The excitation unit is mounted on the shell; wherein the excitation unit is used for driving the first disjunction device to disconnect the connecting bar, and is also used for driving the second disjunction device to disconnect the melt after the first disjunction device disconnects the connecting bar; and when the first breaking device does not cut off the connecting row, the first breaking device blocks the communicating hole. The invention aims to provide the fuse with the arc extinguishing capability and the breaking capability.

The invention relates to the technical field of low-voltage electric appliances, in particular to an arc extinguishing system and a circuit breaker. The arc extinguishing system comprises a shell and an arc extinguishing chamber; a mounting cavity is formed in the shell, and the arc extinguish chamber is arranged in the mounting cavity; a plurality of air outlet holes for exhausting air to the outside are formed in one end of the mounting cavity; the arc extinguishing chamber is provided with an arc extinguishing cavity; a pressure relief channel is further arranged in the mounting cavity, an inlet of the pressure relief channel is communicated with the arc extinguishing cavity, and an outlet of the pressure relief channel is communicated with the air outlet hole. Through the pressure relief channel, the problem that gas impacts the moving and static contacts to cause damage to the moving and static contacts can be avoided; the phenomenon that a large amount of gas carrying charged particles flows between the moving contact and the static contact to cause breakdown between the moving contact and the static contact can be relieved, and the breaking capacity of the arc extinguishing system is further improved; in addition, charged particles or electric arcs entering the pressure relief channel can be gradually cooled in the pressure relief channel, and therefore the arc extinction effect is improved.

The invention discloses a vacuum arc extinguish chamber structure with large rated current and strong breaking capacity, which comprises a structure body, and is characterized in that the structure body comprises a static contact assembly, the static contact assembly comprises a static end arc contact and a static end main contact, and the static end arc contact is arranged in front of the static end main contact and protrudes for a preset distance d along the on-off direction; and the moving contact assembly comprises a moving end main contact and a moving end arc contact, and the moving end main contact and the moving end arc contact are located on the same plane. According to the invention, the effect that the main contact does not burn arc during breaking is realized, the contact surface of the main contact is protected from being ablated by the arc, and a physical foundation is laid for the high capacity of the vacuum arc-extinguishing chamber. The moving end arc contact is provided with a coil structure so as to generate a transverse magnetic field or a longitudinal magnetic field, and the magnetic lines of force between the static end arc contact and the moving end arc contact have the combined action of the longitudinal magnetic field and the transverse magnetic field, so that the breaking capacity is high.

The application relates to the field of low-voltage electrical apparatus, in particular to a contact system and a switch electrical apparatus comprising the same, the contact system comprising a pivotally arranged rotary contact structure and at least one movable contact structure, the rotary contact structure comprising a rotary contact, the rotary contact comprising a rotary contact part, the movable contact structure comprising a movable contact, the movable contact comprising a movable contact part, the rotary contact part and the movable contact part being combined to make the rotary contact and the movable contact closed when the rotary contact is in a closed position; the movable contact structure further comprising an elastic member matched with the movable contact; during the breaking process of the rotary contact and the movable contact, the elastic member stores energy when the rotary contact part drives the movable contact part to move from an initial position to a disengagement position, the rotary contact continues to rotate, the elastic member releases energy to drive the movable contact part to reset to the initial position; the contact system and the switch electrical apparatus have high breaking capacity.

This application relates to the field of circuit breakers, specifically disclosing a high breaking capacity measuring switch, which includes a housing, a moving contact rotatably disposed within the housing, and a stationary contact disposed within the housing. It also includes an arc-extinguishing chamber and an arc-pulling assembly disposed on the arc-extinguishing chamber. The arc-pulling assembly is located on the side of the moving contact away from the stationary contact. The arc-pulling assembly includes a first permanent magnet and a second permanent magnet symmetrically arranged, with an arc-pulling channel formed between the first and second permanent magnets. The arc-pulling channel is located on the moving path of the moving contact. This application improves the arc-extinguishing performance of the measuring switch.

The utility model relates to the technical field of low-voltage switching devices, in particular to an arc extinguishing grid plate and an arc extinguishing chamber. The arc extinguishing grid sheet provided by the utility model comprises a body; the upper end of the body is provided with a first end face and a second end face, and the first end face and the second end face are different in height. The upper end of the body is provided with at least one arc cutting groove located between the first end face and the second end face, and the arc cutting groove penetrates through the two sides of the body in the thickness direction of the body. When the arc extinguishing grid sheets are assembled into a grid sheet group in a positive and negative staggered manner, the first end face and the second end face which are not equal in height can enable the notches of the grid sheet group to be arranged in a front and back staggered manner, the grid sheet group is located below the edges of the two sides of the moving contact of the contact assembly, after the point of the moving contact discharges, the arc can directly correspond to the notches of the arc cutting grooves, and the resistance cut by the body is smaller; the first end face and the second end face which are not equal in height can enable the notches of the grid plate group to be arranged in a front-back staggered mode, cutting and lengthening of electric arcs are facilitated, and the technical effects of improving the electric arc breaking capacity and rapidly extinguishing the arcs can be achieved.

The invention provides a magnetic field enhanced SF6 circuit breaker intelligent control method and device. According to the method, waveform feature extraction and spectral analysis are carried out by acquiring arc state parameters, an intelligent decision model is constructed by adopting a hybrid machine learning and reinforcement learning algorithm to generate an optimal arc extinguishing control strategy, and differential control is implemented in different stages of an arc: an electromagnetic coil is activated in the initial stage to generate a high-intensity magnetic field to apply Lorentz force; synergistically adjusting the magnetic field and airflow in the middle stage, and strengthening airflow cooling in the later stage; meanwhile, the medium recovery characteristic is monitored, the reignition probability is calculated in real time, protection measures are triggered, the fault diagnosis function is integrated, intelligent arc extinguishing control over the SF6 circuit breaker is achieved, and the large-current breaking capacity and reliability are remarkably improved.

The invention relates to the field of circuit protection and contactors, in particular to a three-stable-state permanent magnet contactor, which comprises a driving system and a contact system, and is characterized in that the driving system comprises a driving coil, a permanent magnet assembly, a movable iron core, a first static iron core, a second static iron core and a first counter-force elastic piece; the magnetic field force is generated through forward energization of the driving coil, or power failure or reverse energization of the driving coil, normal closing, normal opening and large-fracture opening are achieved under the combined action of the first counter-force elastic piece and the permanent magnet assembly, and the magnetic field force is generated by adjusting the energization current and energization time of the driving coil. Under the combined action of the first counter-force elastic piece and the permanent magnet assembly, each mechanism after large-fracture opening can be reset to a normal opening position or a normal closing position. According to the three-stable-state permanent magnet contactor, the repeatable actions of normal opening and closing, abnormal opening and mechanism resetting can be achieved, the breaking capacity of the contactor is improved while the function of the contactor is improved, and the service life of the contactor is prolonged.

The utility model discloses a breaker arc extinguishing exhaust system, which comprises an arc extinguishing chamber body, and a plurality of upper exhaust holes and a plurality of lower exhaust holes which are arranged at the rear end of the arc extinguishing chamber body in a vertically staggered manner, a shell is internally provided with a plurality of groups of partition plate structures which divide an exhaust area into a plurality of exhaust channels, and the plurality of exhaust channels are communicated with the upper exhaust holes and the lower exhaust holes. According to the structure that the partition plate is composed of the upper partition rib and the lower partition rib which abut against each other up and down, in order to avoid the upper exhaust hole and the lower exhaust hole, the staggered parts which are partially overlapped and extend in a staggered mode are arranged between the upper partition rib and the lower partition rib, and the structural layout between the partition ribs and the exhaust holes is reasonably optimized, so that the upper exhaust hole and the lower exhaust hole are prevented from being blocked by the upper partition rib and the lower partition rib; according to the utility model, the arc extinguish chamber body is provided with the plurality of exhaust channels, so that the exhaust smoothness of the arc extinguish chamber body is ensured, the temperature rise and pressure in the arc extinguish chamber are reduced, the explosion risk is reduced, and the electrical insulation performance among the plurality of exhaust channels is realized, thereby improving the arc extinguish capacity and breaking capacity of the product.

The present invention discloses a method for generating the short - circuit breaking voltage and current waveforms of a circuit breaker and obtaining parameters, which is characterized in that by obtaining the positive - sequence reactance X1, positive - sequence resistance R1, and zero - sequence reactance X0 of the node where the circuit breaker is located, the total current, alternating - current component current, direct - current component current, and power - frequency recovery voltage during the short - circuit breaking process of the circuit breaker are calculated by applying a three - phase equivalent circuit model. Further, the parameters of the last half - wave of the short - circuit breaking current are obtained: the duration ΔT, the peak value I peak , the direct - current component p at the current zero - crossing point, and from p, the di / dt at the current zero - crossing point and the TRV parameters under the condition of modified asymmetrical short - circuit breaking can be calculated. The short - circuit breaking voltage and current parameters of the high - voltage alternating - current circuit breaker obtained by the method of the present invention can provide reference and basis for the evaluation of the breaking capacity of the circuit breaker and phase - selective breaking.

The invention discloses a surface-mounted tubular fuse structure and a preparation method thereof, and belongs to the technical field of overcurrent protection electronic components. The fuse structure comprises an insulating tube, a fuse body, an arc extinguishing body, an inner copper cap, an outer copper cap and a sealing colloid. The fuse body is arranged in the insulating tube body, the arc extinguishing body is filled in the insulating tube body and wraps the fuse body, the inner copper cap and the outer copper cap form a combined electrode cap, the sealing colloid is filled between the end part of the insulating tube body and a circular inner cap of the combined electrode cap, and the circular inner copper cap and the end part of the insulating tube body realize preliminary airtight packaging through welding or interference fit. And the sealing colloid is combined for secondary reinforced sealing, and the square outer copper cap provides a flat surface-mounted welding surface. The preparation method comprises the process steps of inner copper cap pressing, threading and spot welding, arc extinguishing material potting, outer copper cap assembling, sealant potting and the like. The problems that a traditional tubular fuse is large in installation space, has reliability hidden danger and is limited in high breaking capacity are solved. The fuse is widely applied to the technical field of tubular fuses.

The invention relates to the technical field of copper alloy contacts, in particular to a method for modifying the surface of a copper-chromium contact by adopting a surface laser remelting technology. Comprising the following steps: S1, carrying out sand blasting treatment on the copper-chromium contact; s2, carrying out laser remelting on the copper-chromium contact subjected to sand blasting treatment; and S3, the copper-chromium contact obtained after laser remelting is placed in magnetic grinding equipment, grinding treatment is conducted for 8-12 min, and the modified copper-chromium contact is obtained. The surface of the copper-chromium contact is modified through the laser remelting technology, refining of chromium phase particles can be effectively promoted, and a continuous and compact fine grain strengthening layer with a certain thickness is constructed on the surface layer of the alloy, so that the voltage resistance strength, the breaking capacity and the fusion welding resistance of the copper-chromium contact are comprehensively enhanced.

The invention discloses a double-vacuum fracture multifunctional outdoor pole-mounted switch, which comprises a switch body, an operating mechanism, a transmission mechanism, two vacuum arc-extinguishing chambers, a current transformer and a controller, and is characterized in that the two vacuum arc-extinguishing chambers comprise a first vacuum arc-extinguishing chamber and a second vacuum arc-extinguishing chamber; the first vacuum arc-extinguishing chamber and the second vacuum arc-extinguishing chamber are arranged on the two sides of the same pole in a series connection mode, the first vacuum arc-extinguishing chamber and the second vacuum arc-extinguishing chamber are arranged in series, a single-time breaking task is distributed to the two arc-extinguishing chambers, the short-circuit current breaking capacity is remarkably improved, the contact ablation risk is reduced, the service life of the switch is prolonged, and the service life of the switch is prolonged. The mechanical interlocking design of the manual operation unit and the electric operation unit ensures that emergency operation can still be carried out through a circuit breaker opening and closing handle when a power failure occurs or a control system breaks down, an isolation operation handle independently controls an isolation static contact through an isolation insulation pull rod, step-by-step operation of the circuit breaker and an isolation disconnecting link is achieved, the maintenance safety requirement is met, and the maintenance cost is reduced. And the mistaken touch risk is reduced.

The circuit breaker comprises a shell, an operating mechanism, a traction rod, a protection mechanism, at least one rotating shaft system, and a static contact and an arc extinguish chamber which respectively correspond to the rotating shaft system, the protection mechanism comprises at least one air blowing mechanism, the rotating shaft system, the static contact and the arc extinguish chamber are arranged at intervals in the width direction of the circuit breaker, the operating mechanism is located above the rotating shaft system, the arc extinguish chamber is located above the static contact, and the arc extinguish chamber is located on one side of the operating mechanism in the length direction of the circuit breaker. The draw bar is rotatably arranged on the other side of the operating mechanism, the length direction of the air blowing mechanism is arranged along the length direction of the circuit breaker, one end of the air blowing mechanism in the length direction is located between two adjacent arc extinguish chambers, and the other end of the air blowing mechanism in the length direction is arranged opposite to the draw bar; the sliding direction of the push rod of the air blowing mechanism is arranged along the length of the circuit breaker. According to the circuit breaker, the overall layout of the circuit breaker is compact and reasonable, the air blowing mechanism is horizontally arranged in the circuit breaker, and the breaking capacity of the circuit breaker is improved.

A direct current contactor contact structure comprises an insulating base and two static contacts, a push rod is connected below the insulating base, a contact hoop is installed above the insulating base, a moving contact is installed in the contact hoop, and a spring is installed between the lower surface of the moving contact and the bottom of an inner cavity of the contact hoop. The lower surfaces of the two static contacts vertically correspond to the two ends of the upper surface of the moving contact respectively. Two sides of the upper surface of the moving contact are respectively provided with a contact blade, the middle of the contact blade is provided with a strip-shaped notch, and the strip-shaped notch divides the contact blade into a left contact blade and a right contact blade; and a plurality of spiral grooves are uniformly formed in the lower surface of the static contact in a central symmetry manner. According to the utility model, the defects in the prior art are overcome, the breaking capacity of the contact can be effectively improved, and the thermal load generated by the arc root on the surface of the electrode is reduced, so that the problem that the surface of the contact is locally and seriously melted is prevented.

The arc extinguishing system comprises an arc extinguishing chamber matched with a contact system, the arc extinguishing chamber comprises two arc extinguishing cavities which are communicated with each other, each arc extinguishing cavity is internally provided with at least one grid plate group, the contact system comprises a moving contact assembly and a static contact assembly which are matched with each other, the two arc extinguishing cavities are arranged at an included angle, and the two arc extinguishing cavities are arranged at the included angle. The static contact assembly is arranged at the joint of the two arc extinguishing cavities, the static contact assembly comprises a static arc striking angle, the opening and closing track of the moving contact assembly and one end of the static arc striking angle correspond to an arc inlet of one arc extinguishing cavity, and the other end of the static arc striking angle extends to the other arc extinguishing cavity. And the grid plate groups in the two arc extinguishing cavities are joined at the joint of the two arc extinguishing cavities. According to the utility model, the two arc extinguishing cavities are arranged at the included angle, so that the arc extinguishing grid sheets are additionally arranged in the arc extinguishing chamber in different directions, the breaking performance of high voltage and large current can be considered, and when the arc extinguishing chamber is arranged in the circuit breaker, the arc extinguishing chamber can be enlarged as much as possible in a limited space.

The application relates to a winding type melt fuse, which comprises a shell, a melt arranged in the shell, and contact blades arranged outside the shell and connected with both ends of the melt respectively, wherein a single-layer non-enclosed cylindrical coiled elastic sheet is arranged in the shell, the melt is wound on the outer periphery of the elastic sheet, and a melting weak part of the melt is arranged at an opening on the cylindrical outer periphery of the elastic sheet. The melt fuse can shorten the melt breaking time, improve the breaking capacity and arc extinguishing capacity.

The invention discloses a switching device, a control device and electric equipment. The switching device comprises a shell; the at least two first contact assemblies are arranged on the shell at intervals and are provided with first contacts; the second contact assembly is rotatably arranged on the shell between a first position and a second position and comprises at least two rotating arms, each rotating arm is provided with a second contact, the driving assembly is arranged on the shell and comprises a driving piece and a pushing piece, the pushing piece is matched with the second contact assembly, the driving piece is connected with the pushing piece, and the driving piece is connected with the second contact assembly. The driving piece drives the pushing piece to move so as to drive the second contact assembly to rotate, so that the second contact is in contact with or separated from the first contact. According to the switching device provided by the embodiment of the invention, the opening distance of the second contact is increased, and the current breaking capacity is improved; and the overall structure is simple and compact, the manufacturing cost can be reduced, the reliability of the system is improved, the size of the switching device is reduced, and the switching device is suitable for a scene with a narrow space.

The utility model relates to the field of low-voltage electrical technology of an electric power system, in particular to a static contact assembly and a molded case circuit breaker, a static contact body is composed of an inverted Z-shaped connecting part and an inverted U-shaped contact part, a static contact is arranged on the top end face of the contact part, an arc striking sheet is connected to the lower surface of the static contact body, and the arc striking sheet is connected to the lower surface of the static contact body. The arc striking piece is located at the front end of the static contact and used for pointing to arc striking of an arc extinguish chamber, and the magnetic increasing pieces are connected to the contact part and located on the two sides of the upper portion of the static contact, so that magnetic field distribution is facilitated, the electric repulsive force of a moving contact conducting rod can be greatly increased, the molded case circuit breaker can act faster and more reliably when overload or short circuit or other abnormal conditions happen, and the service life of the molded case circuit breaker is prolonged. Therefore, a better protection effect is provided, the breaking capacity of the molded case circuit breaker is improved, the magnetic increasing sheet is sleeved with the insulating part, current between different potentials is effectively isolated, eddy current is inhibited, electric leakage or short circuit is prevented, the safety of the molded case circuit breaker is improved, and the service life of the contact is prolonged.

This utility model relates to a double-acting arc-extinguishing chamber based on ball screw transmission, including a housing, a moving contact and a stationary contact disposed within the housing, a ball screw rotatably disposed within the housing, a first fixed block fixedly connected to the moving contact, and a second fixed block fixedly connected to the stationary contact. One end of the ball screw is connected to a drive device. The ball screw has a first threaded section and a second threaded section with opposite directions of rotation. The first fixed block is threadedly connected to the first threaded section, and the second fixed block is threadedly connected to the second threaded section. A first guide rail is fixedly disposed on the housing, slidingly engaging with the first fixed block, and a second guide rail is slidably engaged with the second fixed block. This utility model, through ball screw transmission, converts rotational motion into linear motion of the first and second fixed blocks, realizing the opposite or opposite movements of the moving and stationary contacts, improving the closing and opening speeds of the arc-extinguishing chamber, shortening the breaking time, and effectively improving the breaking capacity of the circuit breaker.

This application provides an arc-blocking device and a circuit breaker, belonging to the field of electrical equipment technology. In this arc-blocking device, one end of an elastic element is connected to the circuit breaker housing, and the other end is connected to an arc-blocking element, which is located on the movement trajectory of the circuit breaker's moving contact. When the moving and stationary contacts of the circuit breaker are in contact, the arc-blocking element is located on the side of the moving contact facing away from the stationary contact. During the separation process of the moving and stationary contacts, the moving contact pushes against the first side of the arc-blocking element, causing the arc-blocking element to drive the elastic element to bend and deform in the first direction until the moving contact slips off from the first side. Then, under the elastic force of the elastic element, the arc-blocking element moves in the second direction to between the moving and stationary contacts, thereby forcibly cutting off the arc generated when the moving and stationary contacts separate. It has good breaking capacity and can effectively improve the arc-extinguishing capability of the circuit breaker. Furthermore, the arc-blocking device provided in this embodiment has a simple structure, is easy to assemble, operates reliably, and has a certain degree of universality.

The invention discloses a surge protector, and relates to the technical field of overvoltage protection equipment, and the surge protector comprises a first separation unit and a second separation unit which are connected in series. The first separation unit comprises a first pole piece of the piezoresistor and an electrode piece electrically connected with the wire inlet end, and the first pole piece and the electrode piece are connected through soldering tin to form a first breakpoint. The second separating unit comprises a second pole piece of the piezoresistor, a moving contact electrically connected with the wire outlet end and a separating mechanism, the moving contact is in contact with the second pole piece to form a second breakpoint, the separating mechanism comprises a sliding block and an elastic piece, the electrode piece is fixed to the sliding block, and the sliding block is provided with a firing pin. When surge occurs in the circuit, the soldering tin is fused to disconnect the first breakpoint, the sliding block slides under the action of the elastic piece, and the firing pin pushes the moving contact to be separated from the second pole piece to achieve disconnection of the second breakpoint. According to the surge protector provided by the invention, the breaking capacity of the surge protector can be improved, and the risk of electrical accidents caused by untimely breaking is reduced.

The application discloses a fuse shell and a fuse, and relates to the technical field of fuses, wherein the fuse shell comprises a shell body, at least one first partition and at least one second partition, the shell body is formed with an arc-extinguishing cavity and a buffer cavity distributed along a first direction; the first partition and the second partition are distributed along the first direction, the at least one first partition is arranged between the arc-extinguishing cavity and the buffer cavity, and the at least one second partition is arranged in the buffer cavity; wherein the first partition is provided with a first air vent, the second partition is provided with a second air vent, and the first air vent and the second air vent are arranged in a staggered mode along the first direction. The technical scheme of the application sets the first partition between the arc-extinguishing cavity and the buffer cavity, at least sets the second partition in the buffer cavity, and arranges the first air vent on the first partition and the second air vent on the second partition in a staggered mode, so that the breaking capacity of the fuse is improved, and the breaking effect of zero flying arc is facilitated to be realized.

The invention relates to an SF6 circuit breaker breaking capacity evaluation method and device based on an arc black box model and a medium. The method comprises the steps that a voltage value and a current value in the breaking process of an SF6 circuit breaker are collected; collecting an arcing interval input charge quantity and gas pressure in an arc extinguish chamber under the current on-off working condition; a fitting arc voltage curve is calculated through the voltage value and the current value in the breaking process, and a set of Mayr model parameters are selected according to the difference value between the fitting arc quenching peak and the actual arc quenching peak of the fitting arc voltage curve; substituting the Mayr model parameters, the input charge quantity and the gas pressure in the arc extinguish chamber into a dimensionless relational expression constructed based on dimensional analysis for solving to obtain an on-off constant, determined by historical on-off test data, of the SF6 circuit breaker; and calculating the predicted arc extinguishing peak voltage of the to-be-evaluated SF6 circuit breaker under each on-off working condition so as to evaluate the on-off capability of the to-be-evaluated SF6 circuit breaker. Compared with the prior art, the method has the advantages of low cost, high efficiency, high universality and the like.

The invention belongs to the field of circuit protection, and particularly relates to a self-excitation fuse which comprises a shell, a first conductive part of a cylindrical structure, a first melt, a second conductive part of a cylindrical structure, a first excitation source and a cut-off device, and the first conductive part, the first melt and the second conductive part are sequentially connected in series. The first excitation source and the second melt are respectively connected in parallel at two ends of the first melt; the wiring terminals at two ends of the shell are respectively and electrically connected with the first conductive piece and the second conductive piece; the first excitation source acts according to a trigger signal generated when the first melt is fused, and after the cutting device is driven to cut off an electrical loop where the first conductive part and the second conductive part are located, the second melt is fused or cut off by the cutting device. The circuit breaker is high in breaking capacity, small in product size, high in impact resistance and practical and small in size.

The invention discloses an anti-rebound strong-breaking high-voltage direct-current relay, and the relay comprises a static assembly which is disposed in a relay housing, is used for forming a static conductive and magnetic circuit foundation of the relay, provides a second section of counterforce in the pull-in process of the relay, inhibits the pull-in rebound of a contact, and assists in enhancing the breaking force during breaking. And the movable assembly is arranged in the relay shell and is used for realizing dynamic on-off actions of the contacts. According to the invention, the three-section counter-force design is optimized and combined with the tower-shaped spring, so that the collision energy and bounce of the movable contact can be reduced, the arc generation and the component loss are reduced, and the bonding risk is reduced; breaking force is provided through the synergistic effect of the main spring, the counter-force spring and the magnetic steel, the contact can be assisted to be rapidly separated, and therefore fusion welding is overcome, arc extinguishing is accelerated, and contact damage is reduced. Through the magnetic steel directional polarity and closed magnetic circuit design, the magnetic field intensity can be enhanced, the pull-in response time can be shortened, and the magnetic leakage can be reduced, so that the pull-in force and the holding force can be enhanced, and the contact looseness can be avoided.