72results about How to "Improve current limiting performance" patented technology

Disclosed a short-circuit accidence amperite relates to the accidence amperite of power transmission and distribution network. The invention is characterized in that: it serially connects a current limited resistance an a parallel connection circuit with solid switch on the current limited inductance (common inductance or superconducting inductance) of present bridge short-circuit accidence amperite, and parallel connects a diode (reverse parallel connection) and a afterflow circuit serially connected to the resistance with the current limited inductance, to form said short-circuit accidence amperite. The added afterflow circuit can reduce the A. C. power loss and the back-pressure of current limited inductance. And it utilizes the hysteresis comparison control strategy to realize the switch of current limited resistance. In addition, the provided two connection in series-parallel structure of switch tubes and limited current resistance can meet the demand of high voltage of power network. The invention can limit the peak and the steady-state value of accident current. And said amperite has higher current limited ability, lower effect on the circuit, while it can improve the power quality of power network, and the stability, the safety and the reliability of high voltage or super-high transmission power network.

The invention discloses a power flow controller with a failure current limiting function. When a power grid does not fail, the power flow controller controls current on a current limiting inductor by a current transformer and regulates equivalent impedance flowing into the power grid, thereby controlling the transmission power of the power grid, and compensates the harmonic waves and reactive power of transmission current by the current transformer; and when the power grid fails, the current limiting inductor is directly connected in series to the power grid to function in failure current limiting, and simultaneously, the power flow controller also can control the current transformer to discharge the current limiting inductor and control the current of the current limiting inductor to better current limiting effects, and can perform steady current limiting by a current limiting bypass, with the current limiting inductor, of a protective circuit to better failure current limiting effects.

Conductive polymer current-limiting fuses. when connected in series with conventional mechanical circuit breakers, exhibit extremely low let-through values. Particularly, conductive polymer current-limiting fuses based on conductive elastomeric material are disclosed which exhibit extremely low let-through values, namely less than 5,000 A2s with a switch current of 1.79 kAp, preferably less than 2,500 A2s, most preferably no more than 2,250 A2s.

To provide a current limiting circuit breaker capable of achieving downsizing and cost reduction of a device while improving current limiting performance. The current limiting breaker is provided with a first and a second mechanical switch (10, 10) connected in series, a first diode (11), a first snubber circuit (12), and a first current limiting impedance (13) which are mutually connected in parallel between both ends of the first mechanical switch, and a second diode (11), a second snubber circuit (12), and a second current limiting impedance (13) which are mutually connected in parallel between the both ends of the second mechanical switch. The anodes of the first and the second diodes are connected to each other and connected to the connection point of the first and the second mechanical switches.

The invention discloses a dynamic global traffic limiting method and device, and relates to the technical field of computers. A specific embodiment of the method comprises the steps of obtaining request processing data of each server in a server cluster in a current time window; according to the request processing data of each server in the current time window, determining a total traffic limitingthreshold of the server cluster in the next time window and a resource allocation proportion of each server; determining a traffic limiting threshold of each server in the next time window accordingto the total traffic limiting threshold and the resource allocation proportion of each server; and executing a traffic limiting operation on each server according to the traffic limiting threshold ofeach server in the next time window. According to the embodiment, the total traffic limiting threshold of the server cluster and the traffic limiting threshold of each server can be automatically adjusted according to the request processing data of each server in the server cluster, so that the traffic limiting effect is greatly improved.

This invention relates to a current limiter of short-circuit fault, which applies the mutual inductance theory of magnets and the impedance variance property of superconductive materials in the fault limit composed of a superconductive faulty limiter and a mutual inductor, a winding of which is serial to a superconductive fault limiter then parallel to another winding to adjust mutual inductance and limit fault current by the property that the impedance of the superconductive limiter varies along with the change of current.

The invention relates to a breaker with a forced flash barrier device. The breaker comprises a shell, a movable contact and a fixed contact, wherein the shell is internally provided with a lever made of an insulating material and composed of a left moment arm, a right moment arm and a fulcrum, the left moment arm of the lever is inserted into a gap between the movable contact and the fixed contact since the right moment arm is pushed rightwards by the movable contact during the separation process of the movable contact and the fixed contact, and the left moment arm of the lever goes out of the gap between the movable contact and the fixed contact since the left moment arm is pushed leftwards by the movable contact during the closing process of the movable contact and the fixed contact. The breaker is simple in structure and reliable in movement, can quickly cut off an electric arc when the movable contact and the fixed contact are separated so as to improve arc voltage, increase the breaking capacity and the current-limiting capacity of the breaker, widen the application range of the breaker and realize reversible protection.

The invention discloses an arc extinguishing equipment of a moulded case circuit breaker. The front wall of an arc extinguish chamber is provided with a gas outlet, and the rear wall is provided with a rear opening; the front end of a moving contact stretches into the cavity of the arc extinguish chamber from the exterior through the rear opening; the front end of the moving contact is connected with a moving contact plastic part; the front part of the moving contact plastic part is provided with a groove wrapping the front end of the moving contact; two side walls of the groove are provided with round holes; the moving contact is provided with circular platforms matched with the round holes; the rear end of the groove is provided with a channel; the moving contact is provided with a bard-shaped boss clamped into the channel; the front part of the moving contact plastic part extends towards the rear inferior and is bent with a rear boss; in the repelling process of the moving contact, the rear boss moves to the position which can block the rear opening along with the moving contact to block the rear opening of the arc extinguish chamber to the greatest extent so as to enhance the pressure in the arc extinguish chamber and enhance the air-blowing function in the arc extinguish chamber, and the arc extinguishing equipment can effectively improve the disjunction of the moulded case circuit breaker and enhance the current-limiting performance.

The invention discloses a short-circuit fault current limiter and relates to a short-circuit fault current limiter for a transmission and distribution power grid. The short-circuit fault current limiter is composed of a first electric reactor, a second electric reactor, a double-splitting electric reactor, a capacitor and a switch, wherein a first winding of the double-splitting electric reactor is connected with a second winding in parallel after being connected with the switch in series and then is connected with the capacitor in parallel, a parallel circuit is connected with the second electric reactor in series, and the whole series-parallel circuit and the first electric reactor are connected in parallel to form the short-circuit fault current limiter. According to the short-circuit fault current limiter, through the cooperation between the double-splitting electric reactor and the switch, impedance change and rapid short circuit of the capacitor are achieved during current limiting, the electric reactors are put into use fast, overcurrent impact and overvoltage impact when the double-splitting electric reactor cooperates with the switch are relieved through the parallel connection of the first electric reactor, and the operating reliability and the current limiting capacity of the limiter are improved.

The invention discloses an impedance composite superconducting fault current limiter based on a novel superconducting material. The superconducting fault current limiter comprises a square iron core (18), wherein an MgB2 superconducting winding (11) is arranged on the upper side of the iron core (18) and connected with a reactor (10) in parallel; a high temperature superconducting winding (17) isarranged on the lower side of the iron core (18) and connected with a direct current voltage source (13) in series; and a magnetic switch (16) and a value adjustable first resister (12) are connectedin series between the high temperature superconducting winding (17) and the direct current voltage source (13) to form a first circuit. Under the condition of satisfying the line current-carrying capacity, the superconducting fault current limiter uses the fewest superconductors, can improve the inductive impedance level in case of fault, and also can reduce voltage loss in normal operation and ensure the reliability of operation.

The invention discloses a flow restricting ring, which is simple in structure, good in flow restricting effect and can be adjustable. The flow restricting ring comprises a ring body (1), a flow restricting pillar (2), a ring-shaped bracket (3) sleeved in the ring body (1) and fixedly connected with the flow restricting pillar (2), and a flow restricting rubber ring (4) sleeved on the flow restricting pillar (2), wherein a flow restricting hole (5) is formed between the flow restricting pillar (2) and the ring-shaped bracket (3); an overflow groove (6) is formed at the circumference of the flow restricting pillar (4); an adjusting ring (7) is coaxially arranged above the ring-shaped bracket (3); a plurality of adjusting grooves (8) are formed at the circumference of the ring-shaped bracket (3); and adjusting bulges (9) matched with the adjusting grooves (8) are arranged at the circumference of the adjusting ring (7). The flow restricting ring can be applied to the technical field of wall-mounted furnaces, water heaters and other pipeline equipment.

The invention belongs to low-voltage electrical equipment, and relates to a rotating shaft clamping mechanism in a low-voltage circuit breaker. The rotating shaft clamping mechanism comprises a rotating shaft body and a moving contact terminal, wherein the moving contact terminal horizontally passes through an inner chamber of the rotating shaft body, can rotate around the centre of the rotating shaft body and is symmetrical about the centre; the front and rear ends of the moving contact terminal are provided with moving contacts corresponding to an upper fixed contact and a lower fixed contact on the circuit breaker respectively; the front and rear parts of the symmetrical centre of the moving contact terminal are fixed with a clamping pin extended out of the two sides respectively; the two ends of each clamping pin are towed by a pair of tension springs positioned outside the rotating shaft body; the fixed end of each tension spring is connected to corresponding fixed pins on the two outer sides of the rotating shaft body; the upper and lower edges of the rotating shaft body are provided with a section of cam surface respectively; each cam surface consists of two sunken sections and an arched section; the two sunken sections are positioned at the two ends of the cam surface, while the arched section is positioned on the middle part of the cam surface; and the clamping pins always cling to and are pressed on the corresponding cam surfaces under the action of the tension springs and can stay at the bottoms of the corresponding sunken sections. The rotating shaft clamping mechanism has the characteristics of simple structure, reliable motion and convenient manufacturing and mounting.

Provided is a fault protection applied to a wind power plant and an energy stabilization circuit. A power converter is composed of a voltage source converter and a chopper or a current source converter. A direct current end of a rectifier is connected with a switch provided with an antiparallel diode and a buffer absorption circuit in parallel. A primary side of a single-phase transformer is connected with a switch and a resistor in parallel, and a secondary side of the single-phase transformer is connected with an alternative current output end of the rectifier. The primary side of the single-phase transformer is respectively connected with a power grid and a switching-in end of the wind power plant. A three-phase alternative current end of a power converter is connected with the power grid and a switching-in end of the wind power plant through a three-phase filter circuit and a three-phase transformer. A direct current end of the power converter is connected with a direct current end of the rectifier in series and then connected with an energy storage inductor in series. Under a normal condition, power output of the wind power plant is smoothed through charging and discharging of the energy storage inductor. Under a fault condition, the energy storage inductor is firstly utilized to limit current, then a thyristor of the rectifier is turned off, and the energy storage inductor is disengaged from the power grid. Current is limited through the resistor connected with the primary side of the transformer in parallel.

The invention belongs to low voltage electrical equipment, relating to a contactor falling-resistant device in a low-voltage circuit breaker. The contactor falling-resistant device comprises a spindle body and a moving contact, wherein the moving contact penetrates through the inner cavity of the spindle body from front to back and can rotate around the center of the spindle body; the moving contact is in central symmetry, the front and rear ends of the moving contact are respectively provided with a moving contact point which corresponds to fixed contact points at the upper and lower parts of the circuit breaker; the front and rear part of the centre of symmetry of the moving contact are respectively provided with a chute; each chute is internally provided with a bayonet lock which stretches out of the two sides; two ends of each bayonet lock are dragged by a pair of tension springs positioned outside the spindle body; the fixing ends of the tension springs are connected to fixing pins at two external sides of the spindle body; the upper and lower edges of the spindle body are respectively provided with a section of camming surface which is composed of two hollow sections at two ends and a hunch-up section in the middle; and the bayonet lock is always pressed on the camming surfaces under the action of the tension springs and can stay at the bottoms of the two hollow sections. The invention has simple structure and reliable action and is convenient to manufacture and install.

The invention discloses a saturated bridge type short circuit fault current limiter, which comprises a saturated reactor and a rectifier bridge. The connecting point of a first diode (D1) and a second diode (D2) of the rectifier bridge (Br) is a first alternating current end (A); the connecting point of a third diode (D3) and a fourth diode (D4) of the rectifier bridge (Br) is a second alternating current end (B); the connecting point of the first diode (D1) and the third diode (D3) of the rectifier bridge (Br) is a first direct current end (M); the connecting point of the second diode (D2) and the fourth diode (D4) of the rectifier bridge (Br) is a second direct current end (N); the saturated reactor (L) is connected between the first direct current end (M) and the second direct current end (N); one end of an alternating current power supply (Uac) is connected to the first alternating current end (A); the other end of the alternating current power supply (Uac) is grounded; one end of a circuit breaker (SW) is connected to the second alternating current end (B); the other end of the circuit breaker (SW) is connected with a load (RL) in series and is then grounded. The saturated reactor is realized by a permanent magnet and a direct current coil.

The invention relates to a hybrid short-circuit fault current limiter and a current limiting method. The hybrid short-circuit fault current limiter comprises a current transfer branch and a fault current limiting branch, wherein the current transfer branch comprises a rapid mechanical switch and a power electronic switch in series. In a steady state, a current passes through the current transfer branch, and the loss during normal running is reduced; when a fault occurs, a switch on the transfer branch acts, and the current is transferred to the fault current limiting branch; the fault currentlimiting branch comprises a dual-split reactor and a switch, and a first winding of the dual-split reactor is connected in series with the switch and is connected in parallel with a second winding; the switch is switched on in the steady state, and the fault current limiting branch shows low impedance; and the switch is switched off when the fault occurs, and the fault current limiting branch shows high impedance. By matching of the current transfer branch and the fault current limiting branch, the loss of the current limiter during normal running is reduced, meanwhile, fault current limitingis achieved by the dual-split reactor, and running economy and reliability of the current limiter are improved.

The related discharge-form current limiter for short fault is formed by paralleling an auxiliary inductance and a discharge tube on current device. The production can not only automatic limit fault current peak, but also limits the rise rate and stable value at any time without any control circuit. This invention reduces cost and improves power network reliability and security.

The invention discloses a breaker with a novel arc extinguishing chamber. The breaker with the novel arc extinguishing chamber comprises the arc extinguishing chamber, a static contact current-conducting plate provided with a static contact embedded in the arc extinguishing chamber, and a movable contact embedded in the arc extinguishing chamber and capable of being connected or disconnected with the static contact; the static contact current-conducting plate is further provided with a magnet yoke, the magnet yoke is formed with an open holding groove, and the movable contact is located in the holding groove of the magnet yoke. According to the breaker with the novel arc extinguishing chamber, the static contact current-conducting plate is provided with the magnet yoke, when there is a short in the circuit, the magnet yoke would generate a magnetic field to increase the magnetic blowout intensity and accelerate the electric arc extinguishing. The movable contact is located in the holding groove of the magnet yoke, and therefore, the magnetic field would be in contact with an electric arc in the largest area, and the electric arc can be extinguished quickly.

The present invention provides a circuit breaker which comprises a fixed contact point (1), a movable contact point (3) contacted or separated from the fixed contact point (1), an extinguishing arc mechanism (6), an arc movable conductor (2) located on a side of the fixed contact point for leading the arc to the extinguishing arc mechanism (6), and an arc movable conductor (7) located on a side of the movable contact point. The extinguishing arc mechanism (6) is formed by arranging a plurality of extinguishing arc plates (5), the extinguishing arc plates (5) switch and extinguishing arc generated between the fixed contact point (1) and the movable contact point (3) when the movable contact point (3) is separated, the arc movable conducts (2, 7) are opposite to the extinguishing arc plates by spacing preset clearance respectively. An electric field intensification part is arranged on any one or both side of the relative face of the arc movable conducts (2, 7) and the extinguishing arc plate (5) on external side.

A short trouble current limiter in particular relates to transmission and distribution network failure current limiter. It features on available bridge circuit type short trouble current limiter basic, rectifying bridge arm consisting of controllable solid-state switch tube series connected with current limiting resistance shunt circuit and then series connected with diode. The present invention realizes inductor and resistor combined current limiting, not only limiting failure current peak value but also steady state value.

The invention discloses a self-saturation electric reactor type fault current limiter. The self-saturation electric reactor type fault current limiter comprises a first branch circuit, a second branch circuit and an electric reactor Lc, wherein the first branch circuit and the second branch circuit are connected in parallel, and the electric reactor Lc is connected with the first branch circuit and the second branch circuit in series. The first branch circuit comprises a current limiting protection electric reactor Lb2, a self-saturation electric reactor Lsat and a recovery time current dropping resistor Rj, wherein the current limiting protection electric reactor Lb2, the self-saturation electric reactor Lsat and the recovery time current dropping resistor Rj are sequentially connected in series. The self-saturation electric reactor comprises an iron core and two winding coils. The self-saturation electric reactor type fault current limiter is simple in circuit structure, and has the advantages of being significant in current limiting effect, suitable for wider-range input voltages, reliable, stable, high in practicability and the like.

A circuit breaker can drive the electric arc generated between movable contact-point and fixed contact-point to the direction of arc-suppression device quickly, and can obtain high current limiting performance. The circuit breaker is provided with: an insulation shell body composed of pedestal and shell; a fixed contact component which is installed in the inner of the insulation shell body and has a fixed contact-point in one end; a movable contact component, which has movable contact-point that can contact / separate with the fixed contact-point; an electric arc protection component disposed on the both sides of the fixed contact component; an arc-suppression device which suppresses the electric arc generated when the movable contact component separates from the fixed contact component; and an arc channel, for guiding the arc to the arc-suppression device, provided with a connection unit for connecting the arc generation chamber circled by the electric protection component, arc channel, art-suppression device and the track of the movable contact component with the electric arc gas guide chamber circled by the pedestal, shell, and arc channel, guiding the electric arc gas generated in the electric arc generation chamber to the electric arc gas guide chamber.

A reactor-type short circuit fault current limiter, comprising a first reactor (L1), a second reactor (L2), a switch (K1), a capacitor (C1) and arresters (H1, H2 and H3). The first reactor (L1) consists of a first winding (L11) and a second winding (L12) by intercoupling through a magnetic circuit, one end of the first winding (L11) and one end of the second winding (L12) are connected in parallel to each other at a first connection point (a), and the other end of the first winding (L11) is connected in series to the switch (K1) and then connected in parallel to the other end of the second winding (L12) at a second connection point (b). When the power grid is in a steady state, a current limiter works in a series resonance or series compensation state, and presents a low impedance; when the power grid has a short circuit fault, the windings of a reactor undergo overcurrent saturation, and at the same time, the reactance change of the reactor is controlled by closing a switch, so as to produce a high impedance to achieve fault current limiting. The current limiter enhances the current limiting capacity, reduces the system manufacturing cost, has insignificant impact on the power grid, and improves the operational safety and reliability of the power grid.

The invention discloses a current limiting method of a transformer current limiting device based on manual zero-crossing current limiting. When a short circuit fault occurs, a controller immediately sends a switching-off instruction to a rapid vacuum circuit breaker after judging the short-circuit fault; when the rapid vacuum circuit breaker is switched off and the distance between contacts reaches a rated opening distance, the controller switches on a controllable discharge gap Spark2; a capacitor C2 and an inductor L2 are connected in series for resonance so as to generate reverse high-frequency current equivalent to the instantaneous amplitude of the short-circuit current and superpose the reverse high-frequency current on a rapid vacuum circuit breaker loop; the quick vacuum circuit breaker completes short-circuit current switching-on and switching-off; then, the short-circuit current is transferred to a ZnO branch of a zinc oxide arrester and the capacitor C2 is charged; when thevoltage of the capacitor C2 tends to be stable and reaches the residual voltage of the zinc oxide arrester ZnO, the zinc oxide arrester ZnO is switched on, the controllable discharge gap Spark2 is switched off, then the zinc oxide arrester ZnO continuously absorbs short-circuit current energy, and the zinc oxide arrester ZnO is switched off when the current crosses zero.

The invention relates to a gateway control method and device, electronic equipment and a storage medium; the method comprises the steps: obtaining the quota use condition of each gateway node in a gateway cluster; determining a quota distribution proportion among the gateway nodes based on the quota use condition; determining a second quota of the first gateway node based on the cluster quota and the quota distribution proportion; and sending a quota application notification to the first gateway node, wherein the quota application notification is used for instructing the first gateway node to apply for the traffic limit from the cache database according to the second quota. According to the embodiment of the invention, the dynamic adjustment of the second quotas of all gateway nodes in the gateway cluster in the second period is realized. Therefore, the current limiting effect of the gateway cluster can be improved to a certain extent after each period, and the current limiting quota of each gateway node is fully utilized. According to the method, the current limiting performance is maintained, the current limiting precision of the gateway cluster is improved, and the current limiting effect is improved.

The invention discloses an LDO multi-integrated protection circuit. The LDO multi-integrated protection circuit connected with a basic LDO circuit comprises an input power VDD detection module, a temperature detection module, a current detection module and a protection module integrated and connected. The input power VDD detection module outputs a current Is1, the current detection module outputsa current Is2 corresponding to the basic LDO circuit, the temperature detection module outputs a current Iptc, output currents of the above three modules are connected to an adder, and the protectionmodule is connected among output currents of the detection modules, an input power supply VDD and a grating of a power tube Mp of the basic LDO circuit to realize current limiting protection for the basic LDO circuit. Design of a multi-integrated protection circuit is used, a PTC current generation circuit is introduced, current detection, temperature detection and input voltage detection are fused into integrated LDO protection, the current limiting performance of the LDO is improved reliably, and recovery time of self output IL is shortened.

The invention discloses a ceramic filter flow-limiting valve gate. The ceramic filter flow-limiting valve gate comprises a tube body interconnecting piece, the tube body interconnecting piece is rotatably provided with a control shaft, the control shaft is provided with an operating handle, the bottom of the operating handle is provided with a positioning control rod, an anti-skid whorl is arranged on the surface of the operating handle, and the positioning control rod and the operating handle keep a certain included angle. Due to the operating handle of the valve gate of the ceramic filter flow-limiting valve gate is provided with a control rod used for preventing the operating handle from loosening, and the nonoccurrence of the displacement of a valve gate handle is guaranteed even under a condition of violent vibration of a machine. Accordingly, the flow-limiting effect of the ceramic filter flow-limiting valve gate is greatly improved.

The invention relates to a circuit breaker and solves the problems of poor breaking capability and poor current limiting performance of the circuit breaker. The circuit breaker comprises a casing, wherein a movable contact, a static contact, an arc extinguishing device, a connecting plate and an arc striking sheet are arranged in the casing, the connecting plate is connected with the static contact, an isolation element is arranged between the arc striking sheet and the connecting plate, at least one annular current limiting coil is arranged outside the arc extinguishing device, and the two ends of the current limiting coil are respectively connected with the arc striking sheet and the connecting plate. The circuit breaker has the advantages that a novel current limiting breaking technology is provided, on the premise of not changing the casing size, the breaking performance is irrelevant to a contact material, the extremely high electric arc voltage can be fast obtained, the resistance of the circuit breaker is improved, and the electric arc can be fast extinguished, so the circuit breaker obtains high breaking capability and good current limiting performance.

The invention discloses a subminiature molded case circuit breaker, which comprises a bottom shell, a moving contact mechanism, a fixed contact, an arc extinguishing chamber and a traction rod. The subminiature molded case circuit breaker is characterized in that the traction rod, a traction rod bracket and an armature of a traditional molded case circuit breaker are integrally laminated into an integral structure, so that the size is reduced; a moving contact, the fixed contact and the arc extinguishing chamber of the subminiature molded case circuit breaker within the finite volume can be lengthened; the current limiting capacity of the molded case circuit breaker is improved; the breaking capacity of the subminiature molded case circuit breaker reaches the breaking level of the similar molded case circuit breaker; the working performance is more stable and reliable than that of a miniature circuit breaker while the size is greatly reduced; the subminiature molded case circuit breaker can be arranged on a guide rail for use like the miniature circuit breaker; and the subminiature molded case circuit breaker can be widely applied to building electricity.

The invention discloses a miniature circuit breaker, which belongs to the technical field of low-voltage apparatus. The miniature circuit breaker comprises a moving contact which is mounted in a shell and electrically connected with a first wiring terminal, a static contact which is also mounted in the shell and electrically connected with a second wiring terminal, an arc chute piece which is located in the shell and used for extinguishing the electric arc generated when the moving and static contacts are separated, a moving contact arc striking plate which is corresponding to the moving contact and one end of which is extended to the arc chute piece and the other end is electrically connected with the first wiring terminal, and an electromagnetic coil and thermal element which are distributed on the same side of the moving contact, wherein the electromagnetic coil and the thermal element are connected in series and then connected in series between the moving contact and the first wiring terminal. The invention has the advantages that: the breaking capacity and the electric service life of the miniature circuit breaker are remarkably improved.