49results about How to "Avoid reignite" patented technology

The invention discloses a serial multi-cavity arc-extinguishing lightning-protection device. The device comprises an installation fitting connected to the bottom of a protected circuit insulator and amulti-cavity arc-extinguishing lightning-protection body supported by the installation fitting, the top of the protected circuit insulator is provided with a punctured wire clamp electrode, and a serial main gap is arranged between the punctured wire clamp electrode and the multi-cavity arc-extinguishing lightning-protection body; and the two ends of the multi-cavity arc-extinguishing lightning-protection body are provided with end-portion fittings respectively, the multi-cavity arc-extinguishing lightning-protection body is internally provided with internal electrodes, a gas cavity is formedbetween every two adjacent internal electrodes, and the two internal electrodes positioned in the end portions are connected to the adjacent end-portion fittings respectively. Compared with the priorart, the serial multi-cavity arc-extinguishing lightning-protection device can be produced in a low-cost and batch manner; the device is characterized by simple manufacturing technology, low cost, high lightning protection performance, and stable operation and maintenance, and can be widely popularized; and after operation, the maintenance cost is extremely low, and basically, the device is freeof maintenance.

The invention relates to a flexible arc extinguishing method for a power distribution network based on a single direct current source cascade H-bridge converter. The method comprises the steps of S1,recognizing a fault phase of a grounding fault, enabling a cascade H-bridge converter of the fault phase to be connected with a power distribution network, enabling a cascade H-bridge converter of a non-fault phase to be disconnected with the power distribution network, and initializing parameters of a quasi-PR controller; S2, collecting and comparing a difference value between a fault phase voltage value and a reference value, obtaining an injection current reference value of the cascade H-bridge converter through the quasi-PR controller, and calculating an optimal output level; S3, obtainingan on-off state combination according to the optimal output level, and sending the on-off state combination to the corresponding H-bridge unit; S4, after the preset time delay, cutting off the current-limiting resistor, and adjusting the parameters of the quasi-PR controller; S5, collecting direct-current side voltage of the cascade H-bridge converter in real time, and connecting a direct-currentsource with an H-bridge unit after the voltage drops to a threshold value; and S6, gradually reducing the injection current after the preset time is reached, and judging and isolating the permanent single-phase grounding fault.

The invention provides a non-reignition disconnector which comprises a disconnector arc extinguishing chamber, and further comprises a non-linear pressure-sensitive unit, and the non-linear pressure-sensitive unit is connected with an upper electrified portion and a lower electrified portion of a fracture of the disconnector arc extinguishing chamber in parallel. According to the non-reignition disconnector, the voltage difference between the two ends of the facture is leveled before backward voltage and recovery voltage of the fracture exceed a fracture withstand voltage level, and reignition is eliminated.

The invention discloses a grounding line selection device comprising the following units connected in series between a bus terminal (A-B-C) and a grounding terminal (D): a three-phase synchronous operation switch (K3) and a ground transformer (B), a phase separation control switch (K1), an impedor (R1) and a second current transformer (CT2), a phase selection switch (K2) connected in parallel on two ends of the impedor (R1), a voltage sensor (PT), and a controller (KZQ) electrically connected with a branch zero sequence current sensor (CT3-CTn); when single phase grounding faults happen, the controller (KZQ) firstly soft closes a soft switch branch, than closes a grounding transformer branch; when the controller determines the grounding fault is an instant singlephase earth fault according to conditions in which the output of the second current transformer is <=1A, cuts off the soft switch branch and the grounding transformer branch, otherwise, combines with the branch zero sequence current sensor output determination so as to realize line selection and positioning, and disconnects the grounding transformer branch. The grounding line selection device is easily and widely applied to commercialization earth fault processing and line selection fields.

The invention relates to a circuit breaker, and specifically relates to an improvement of a tripping mechanism of the circuit breaker. A moving contact is rapidly repelled by utilizing the Holm forceand the Lorentz force generated by the short-circuit current; when the moving contact is repelled, a tripping combined structure is designed for transmission by utilizing the repelling movement, so that a tripping half shaft and a tripping piece are directly unbuckled, the mechanism response time is shortened, the capability of cutting off the fault current is improved, and the impact of the faultcurrent on the system is reduced. In addition, the contact is prevented from being closed with a static contact again after being repelled by using a connecting rod transmission direct tripping mode,the arc reignition is prevented, the burning loss of the contact is reduced, and the arc extinguishing difficulty is reduced.

The invention relates to an arc control device in a load switch, which is particularly applicable to SF6 gas-filled switching equipment, belonging to the technical field of intermediate voltage electric equipment. The arc control device is characterized in that an arc control grid is improved to have a frame structure with an open front and an back, is benefit for the insert connection with a flat arc control grid sheet\; the arc control grid sheet is provided with grooves and holes in pattern which are asymmetric, so that an electric arc can be stretched and can be cut into a plurality of short electric arcs to effectively prevent arc restrike after current passes zero and improve the performance of arc control. The arc control grid sheet is made of a silicon-steel plate, electric pure iron and other magnetic conductive materials, and the excellent magnetic conductive performance ensures that the electric arc can be automatically introduced into the arc control device under the action of electromagnetic field force, thereby improving the effect of arc control. Because the arc control grid sheet has a sheet shaped structure without a special mould, the arc control grid sheet becomes simply through processing by laser cutting equipment or numerical punching equipment. The arc control device has the advantages of simple structure, good arc control performance and strong practicality, and can replace the prior arc control device in the prior load switch.

The present invention provides a breaker. The breaker comprises a pair of mutually cooperated moving contact and static contact, an arc extinguish chamber and an arc ignition runway facing the end protruding of the static contact and being divided into a first segment and a second segment through a protruding portion, wherein the free end of the first segment is close to the tail end of the moving contact, the free end of the second segment extends into the arc extinguish chamber, and the distance of the tail end of the static contact is smaller than the distance from any one point on the arc ignition runway to the tail end of the static contact. The breaker can allow the arc to rapidly depart from a contact area after formation and jump to the arc ignition runway so as to reduce the ablation of the arc to the contact; and moreover, the arc can be rapidly pushed to the arc extinguish chamber to effectively avoid the countermovement of the arc and the reigniting of the contact area.

The invention discloses a switch restrike limiting device. The device comprises a breaker (2) connected with a circuit in series and a controller (7) electrically connected with the control terminal of the breaker (2), a breaker fracture restrike limiting branch is connected with two ends of the breaker (2) in parallel, the breaker fracture restrike limiting branch comprises a switch (3), a damping resistor (4) and a capacitor (5) which are connected in series, a zinc oxide component (6) is parallelly connected with the damping resistor (4) and the capacitor (5) which are connected in series, the control terminal of the switch (3) is electrically connected with the auxiliary switch of the breaker (2), when the controller (7) controls breaker (2) breaking, the auxiliary switch of the breaker (2) delays to break the switch (3). According to the invention, the device can not have overvoltage when breaking inductive or capacitive load, restriking of breaker (2) fracture is avoided, and the device can be widely applied in breaker restrike-free breaking on the electric circuit.

The invention discloses a phase selection switch controller which comprises an upper machine communication module, a main control module, a signal processing and collecting module, a charging and discharging control module of an energy storing capacitor and a safety interlocking module. The main control module is mainly composed of a DSP system, an external RAM and a man-machine interface. The signal processing and collecting module is composed of an analog signal conditioning unit, a logic control unit and a digit collecting unit. The charging and discharging control module of the energy storing capacitor is composed of an AC/DC high-frequency switch power supply, a discharging and energy storing capacitor C, a protective diode and a photoelectric coupler. The phase selection switch controller has the advantages that during closing and opening of the capacitor, inrush currents are reduced, overvoltage is hindered, a series reactor is not needed, the overhauling period and the service life of a high-voltage switch are prolonged, re-ignition and re-strike are prevented and the insulating level of equipment is lowered. When fault currents are cut off, the cut-off capability is improved, abrasion of the switch is reduced, stability of the system is improved and the service life of the switch is prolonged.

The invention discloses an electromagnetic relay for a high-voltage-withstanding and heavy-current load. The electromagnetic relay comprises two moving contacts, a moving reed in bridge connection with the two moving contacts, and two static contacts matching the two moving contact correspondingly. One of the static contacts is set to be a current flowing-in side and the other of the static contacts is set to be a current flow-out side, so that arcs generated between the two pairs of contacts splatter outwardly along connecting lines of gaps of the two pairs of contacts. First arc-guiding pieces for stopping corresponding arcs from splattering towards the outer sides along connecting lines of gaps of the two pairs of contacts are arranged at the outer sides of the connecting lines of gaps of the two pairs of contacts; the first arc-guiding pieces made of conductive metal materials are arranged obliquely relative to the connecting lines of gaps of the two pairs of contacts, so that the stopped arcs can be guided to move along the preset arc guiding directions of the first arc-guiding pieces. Therefore, cutting off of the high-voltage and heavy-current load can be realized; plastic burning by arcs can be avoided; and the arc energy can be reduced. The electromagnetic relay is also suitable for alternating-current and direct-current loads.

The invention relates to the technical field of a circuit breaker, specifically to a small-sized circuit breaker. The circuit breaker comprises a contact assembly which comprises a movable contact (6) and a static contact (7), a driving mechanism (2) used for driving the movable contact (6) and the static contact (7) to switch on or switch off, an arc extinguishing apparatus (3) arranged on one side of the contact assembly, and a locking structure which is arranged at one end, equipped with a movable contact point, of the movable contact (6) or the arc extinguishing apparatus (3), wherein the locking structure performs locking of the movable contact (6) and the arc extinguishing apparatus (3) when the movable contact (6) moves to a position which is farthest from the static contact (7) in a switch-off direction, and performs unlocking when the driving mechanism (2) applies switch-on force to the movable contact (6). By virtue of the small-sized circuit breaker provided by the invention, electric arc re-ignition caused by the fact that the movable contact rebounds or even moves to a distance of electric arc breakdown when the movable contact is separated from the static contact and is in collision and contact with an arc striking plate can be avoided effectively.

A method for synchronizing opening of a circuit breaker is presented. The circuit breaker is arranged to interrupt a current to an inductive load. The method is performed in a control device (2) and comprises measuring (S100) a reference signal as a function of time for a circuit breaker (1) connected to an inductive load (5), obtaining (S110) an indication of a power factor of the inductive loadthrough the circuit breaker, determining (S120) an arcing time for opening of the circuit breaker, the arcing time being dependent on the obtained indication of a power factor, predicting (S130) a zero crossing of a current through the circuit breaker based on the measured reference signal, and providing (S140) contact separation of a contact pair of the circuit breaker at a point of time before the predicted zero crossing, the point of time being determined by the determined arcing time and the predicted zero crossing. A control device, a circuit breaker arrangement, and a computer program for synchronizing opening of a circuit breaker are also presented.

The invention discloses an arc extinguishing method of a recoil arc extinguishing lightning protection insulator, and belongs to the technical field of lightning protection. When a tower or a power transmission line lead is struck by lightning and insulator flashover occurs, lightning arc always selects a channel which is shortest in path and is most conductive to the ground to be discharged to the ground. A plurality of recoil pipes which are installed on the periphery of the skirt edge and swing left and right at a certain inclination angle form an arc extinguishing channel, the channel shortens the length of a lightning stroke flashover path through lightning arresting electrodes in the recoil arc extinguishing pipes to play a role in insulation matching, and the lightning stroke flashover path is overlapped with the recoil arc extinguishing channel according to the control rule of insulation matching. According to the invention, the effect of step-by-step arc extinguishing through the plurality of recoil pipes is good, the process of impacting an arc building channel and inhibiting power frequency arc building can be effectively destroyed, and compared with a traditional insulator, the insulator additionally provided with the recoil pipes can be used for backflushing and jetting a flowing arc so that the effects of protecting the insulator and preventing the insulator from bearing huge pressure are achieved.

The invention provides a delay coupling mixed airflow arc extinguishing lightning protection device. The delay coupling mixed airflow arc extinguishing lightning protection device comprises two lightning protection insulator main bodies, a grading ring, a skirt edge, a low-voltage grounding electrode and a high-voltage electrode, one ends of the two lightning protection insulator main bodies are connected through a low-voltage grounding electrode, and the other ends are connected through a high-voltage electrode; the two ends of each lightning protection insulator main body are provided with grading rings, and each lightning protection insulator main body is provided with a plurality of skirt edges. An arc extinguishing path is arranged in each lightning protection insulator main body; the arc extinguishing path is mainly composed of a plurality of longitudinal blowing airflow arc extinguishing main bodies and a plurality of transverse blowing airflow arc extinguishing pipelines; the two ends of the arc extinguishing path are both longitudinal blowing airflow arc extinguishing bodies, and a transverse blowing airflow arc extinguishing pipeline is arranged between every two adjacent longitudinal blowing airflow arc extinguishing bodies. According to the lightning protection device, the arc extinguishing effect and the insulating effect of the lightning protection device formed by parallel connection are improved in a mode of combining the insulating string and the arc extinguishing units, meanwhile, the arc extinguishing path is lengthened by utilizing a transverse and longitudinal blowing arc extinguishing mode in the arc extinguishing chamber, the arc extinguishing time is shortened, and therefore the arc extinguishing effect is improved.