Repulsion mechanism and its application of reactive power equipment switching overvoltage protection device

Abstract

The present application relates to a repulsion mechanism for reactive device switching protection and a reactive device switching overvoltage protection device using the same, which comprises a repulsion mechanism for driving a vacuum interrupter to perform closing and opening actions. The repulsion mechanism comprises at least one repulsion disc, and each of the two disc surfaces of the same repulsion disc is equipped with a coil disc, and the two coil discs share the same buffer assembly. The buffer assembly can control the establishment and change of the magnetic field of the two coil discs, optimizes the configuration number of the buffer assembly in the prior art, is conducive to reducing the space of the inrush current and overvoltage protection device, and promotes the miniaturization of the product. The vacuum interrupter of the phase control switch uses the repulsion mechanism to drive it to perform closing and opening actions, and the phase control switch is provided with silicon stacks and energy absorption assemblies in parallel, the inrush current is inhibited by the silicon stacks, and the overvoltage is inhibited by the energy absorption assemblies.

Description

TECHNICAL FIELD

[0001] The present application relates to the switching protection of reactive devices, in particular to the inrush current and overvoltage protection of switching process. BACKGROUND

[0002] To improve the power quality problem of power grid, one of the common ways is to use shunt capacitor banks to compensate for inductive reactive power, so as to improve the system voltage and power factor and reduce line loss.

[0003] The capacitor bank is switched by a circuit breaker in the power grid system, and in order to suppress the inrush current and overvoltage generated during the switching of the capacitor bank, the circuit breaker responsible for the switching of the capacitor bank is replaced by an inrush current and overvoltage protection device, and the switching operation of the capacitor bank is completed by the cooperation of the fast switch (one circuit breaker) and the bypass circuit breaker (another circuit breaker) in the device.

[0004] Among them, the common way to drive the opening and closing of the circuit breaker is two: one is to use the traditional mechanical connecting rod mechanism to drive the movement of the moving rod of the vacuum arc chamber, so that the moving rod contact and the static rod contact open and close; the second is to use the electromagnetic characteristics, through the repulsion mechanism composed of coil disc and repulsion disc to drive the movement of the moving rod of the vacuum arc chamber, so that the moving rod contact and the static rod contact open and close.

[0005] For example, the Chinese patent application with publication number CN118366815A, its circuit breaker not only adopts the second driving method described above, but also adds a buffer device, which reduces the degree of hard collision between the repulsion disc and the coil disc, so as to reduce the wear of the repulsion disc and the coil disc, so that the circuit breaker can be applied to the power grid system with high switching frequency.

[0006] However, in a three-phase line, the inrush current and overvoltage protection device needs to connect at least two groups of vacuum arc chambers for each phase line, and each group of vacuum arc chamber moving end is connected with at least two coil discs, and each coil disc is equipped with a fixed resistor, an adjustable resistor and a group of energy storage capacitors for opening and closing.

[0007] Therefore, a set of inrush current and overvoltage protection device needs at least six fixed resistors, six adjustable resistors and six groups of energy storage capacitors, which not only increases the production cost, but also occupies more space, which is not conducive to the miniaturization of the product. SUMMARY

[0008] In order to solve the problem of increasing cost and occupying space caused by the large number of components in the coil disc of the inrush current and overvoltage protection device in the background art, the present application provides the following technical solutions:

[0009] A repulsion mechanism, which comprises at least one repulsion disc, and each of the two disc faces of the same repulsion disc is equipped with a coil disc, the two coil discs are connected in parallel and share the same power supply circuit, and the power supply circuit is equipped with a buffer assembly.

[0010] The buffer assembly comprises a fixed resistor and an adjustable resistor, both of which are connected in parallel and are respectively connected in series with the two coil discs to form four series branches, and each series branch is connected with a branch switch to control the on-off of the series branch.

[0011] During the closing and opening process of the vacuum interrupter, the series branch of the coil disc and the adjustable resistor connected in series with the coil disc close to the repulsion disc is in the on state, and the resistance value of the adjustable resistor increases, while the series branch of the coil disc and the fixed resistor connected in series with the coil disc away from the repulsion disc is in the on state, and the remaining series branches are in the off state.

[0012] Further, when the series branch of the coil disc and the fixed resistor connected in series with the coil disc is in the on state, the coil disc is powered to establish a stable magnetic field; when the series branch of the coil disc and the adjustable resistor connected in series with the coil disc is in the on state, the coil disc is powered to establish a magnetic field that decays.

[0013] Further, the resistance value of the adjustable resistor when it is just in the on state is greater than the resistance value of the fixed resistor.

[0014] Further, the outer end of the moving rod of the vacuum interrupter is provided with a pull-down rod. The repulsion disc is installed on the rod body of the pull-down rod; the coil disc does not contact the pull-down rod. The pull-down rod is driven to move by the change of the magnetic field between the repulsion disc and the coil disc to make the vacuum interrupter perform the closing and opening action.

[0015] Further, the adjustable resistor comprises a resistance piece one and a sliding piece, and the resistance value of the adjustable resistor is changed by the sliding of the sliding piece along the surface of the resistance piece one.

[0016] Further, one end of the resistance piece one and the sliding piece are respectively provided with a terminal, and the two terminals are respectively connected as the input and output terminals of the adjustable resistor between the coil disc and the energy storage capacitor of the power supply circuit.

[0017] Further, one end of the resistance piece one and the sliding piece are respectively provided with a terminal, and the two terminals are respectively connected as the input and output terminals of the adjustable resistor between the coil disc and the energy storage capacitor of the power supply circuit.

[0018] Further, the fixed resistor comprises a resistance piece two, and each end of the resistance piece two is provided with a terminal, and the two terminals are respectively connected as the input and output terminals of the fixed resistor between the coil disc and the energy storage capacitor of the power supply circuit.

[0019] Further, the movable rod outer end of the vacuum interrupter is provided with a lower pull rod, and a slot is formed in the rod body of the lower pull rod.

[0020] The inrush current and overvoltage protection device for reactive equipment switching comprises a three-phase circuit breaker, a phase control switch connected to each phase outgoing line of the three-phase circuit breaker, a silicon stack and an energy absorption assembly connected in parallel with the phase control switch, and the silicon stack and the energy absorption assembly are connected in parallel, and the outgoing line of the phase control switch is connected with the reactive equipment, and the vacuum interrupter of the phase control switch is driven to perform closing and opening operations by the repulsion mechanism.

[0021] Compared with the prior art, the beneficial effects of the present application are:

[0022] I. The same power supply circuit is shared by the two coil plates equipped with the same repulsion plate, and the buffer assembly of the power supply circuit can control the establishment and change of the magnetic field of the two coil plates, optimizing the number of buffer assemblies in the prior art and reducing the production cost of the inrush current and overvoltage protection device;

[0023] II. The same power supply circuit is shared by the two coil plates equipped with the same repulsion plate, and the buffer assembly of the power supply circuit can control the establishment and change of the magnetic field of the two coil plates, optimizing the number of buffer assemblies in the prior art and reducing the space of the inrush current and overvoltage protection device, promoting the miniaturization of the product;

[0024] III. The adjustable resistor in the buffer assembly can adopt the principle of slide rheostat, and the resistor one is installed in the lower pull rod, so that the resistor one can be synchronously adjusted in resistance value following the movement of the lower pull rod, without the need for additional tools and energy to regulate the resistance value change of the resistor one;

[0025] IV. The phase control device is connected in parallel with the phase control switch, and the silicon stack is built-in in the phase control device, and by connecting the silicon stack in parallel with the phase control switch, when the three-phase circuit breaker is in the closed state and the phase control switch is in the open state, the current is suppressed by the silicon stack;

[0026] V. The phase control device is connected in parallel with the phase control switch, and the energy absorption assembly is built-in in the phase control device, and by connecting the energy absorption assembly in parallel with the phase control switch and the silicon stack, when the three-phase circuit breaker is in the closed state and the phase control switch is in the open state, and the voltage across the phase control switch and the silicon stack is too high to meet the conduction condition of the energy absorption assembly, the current is shunted to the energy absorption assembly and consumed by the energy absorption assembly, thereby suppressing the overvoltage;

[0027] Six, by the buffer assembly adjusting the coil disc and the repulsion disc between the strength of the magnetic field changes, not only can use repulsion magnetic field to achieve the vacuum interrupter combined with the brake, but also can use repulsion magnetic field to form a buffer area, both to avoid the hard collision between them, and reduce the noise generated when the contact between them;

[0028] Seven, the repulsion disc uses permanent magnet design, and the coil disc adds the material that can be adsorbed by the repulsion disc, which can directly cancel the iron core and permanent magnet used to maintain the vacuum interrupter combined with the brake in the prior art, saving production cost, reducing the space occupation of this part, and being conducive to the miniaturization design of the device. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 For the switching connection diagram of the reactive device;

[0030] Figure 2 For the switching connection diagram of the surge and overvoltage protection device;

[0031] Figure 3 For the single coil disc connection diagram of the eddy current driven switch;

[0032] Figure 4 For the double coil disc connection diagram of the eddy current driven switch;

[0033] Figure 5 For the switching switch closing state diagram;

[0034] Figure 6 For the switching switch opening state diagram;

[0035] Figure 7 For Figure 5 the enlarged view of A;

[0036] Figure 8 For Figure 6 the enlarged view of B;

[0037] Figure 9 For the eddy current driving schematic diagram.

[0038] In the drawings, the names of the parts represented by the respective reference signs are listed as follows:

[0039] 1 - lower pull rod, 2 - repulsion disc, 3 - coil disc, 4 - resistance piece one, 5 - slide, 6 - resistance piece two. DETAILED DESCRIPTION

[0040] The preferred specific embodiments for realizing the present application are described in detail below, and a clear and complete description is made in conjunction with the drawings.

[0041] Please refer to Figures 1-3 , and Figure 9 , in the drawings:

[0042] A, B and C represent A-phase line, B-phase line and C-phase line in three-phase branch where the reactive power equipment is located, respectively;

[0043] PT represents voltage transformer;

[0044] K Z represents three-phase circuit breaker;

[0045] K a , K b and K c all represent phase-controlled switch;

[0046] D a , D b and D c all represent phase-controlled device;

[0047] CT a , CT b and CT c all represent current sensor;

[0048] C Z represents reactive power equipment, i.e. capacitor bank for reactive power compensation;

[0049] TL represents silicon stack in phase-controlled device for suppressing inrush current;

[0050] ZGD-B represents energy-absorbing component in phase-controlled device for suppressing overvoltage, such as zinc oxide valve stack;

[0051] R1 and R2 represent fixed resistor and adjustable resistor, respectively;

[0052] K1 and K2 all represent branch switch;

[0053] K represents bypass switch.

[0054] In prior art, the reactive power equipment is connected to power grid system through three-phase branch. Among them:

[0055] Three-phase circuit breaker K Z serves as total switch of three-phase branch where the reactive power equipment is located;

[0056] Voltage transformer PT is located at incoming line side of three-phase circuit breaker K Z and is connected between B-phase line and C-phase line;

[0057] Phase-controlled switches K a , K b and K c are connected to A-phase line, B-phase line and C-phase line at outgoing line side of three-phase circuit breaker K Z respectively, and phase-controlled switch K a is used for controlling three-phase circuit breaker K ZThe on-off of the A-phase line on the outgoing side, phase-controlled switch K b For controlling the three-phase circuit breaker K Z The on-off of the B-phase line on the outgoing side, phase-controlled switch K c For controlling the three-phase circuit breaker K Z The on-off of the C-phase line on the outgoing side;

[0058] Phase-controlled device D a , D b and D c are connected in parallel with phase-controlled switch K a , K b and K c respectively, that is, phase-controlled device D a is connected in parallel with phase-controlled switch K a , phase-controlled device D b is connected in parallel with phase-controlled switch K b , and phase-controlled device D c is connected in parallel with phase-controlled switch K c ;

[0059] Any one of phase-controlled device D a , D b and D c is composed of a silicon stack TL and an energy-absorbing component ZGD-B, both of which are connected in parallel with the corresponding phase-controlled switch K a , K b or K c , and the energy-absorbing component ZGD-B is grounded at the end, that is, the silicon stack TL and the energy-absorbing component ZGD-B in phase-controlled device D a are connected in parallel with phase-controlled switch K a , the silicon stack TL and the energy-absorbing component ZGD-B in phase-controlled device D b are connected in parallel with phase-controlled switch K b , and the silicon stack TL and the energy-absorbing component ZGD-B in phase-controlled device D c are connected in parallel with phase-controlled switch K c ;

[0060] Current sensor CT a , CT b and CT c are respectively installed on the A-phase line, the B-phase line and the C-phase line on the outgoing side of the three-phase circuit breaker K Z , and current sensor CT a is located on the outgoing side of phase-controlled switch K a , current sensor CT b is located on the outgoing side of phase-controlled switch K b , and current sensor CT c is located on the outgoing side of phase-controlled switch K c ;

[0061] Phase-controlled switch K a , K b and K c Each vacuum interrupter of the three-phase circuit breaker K Z is equipped with at least two coil discs 3, and each coil disc 3 is equipped with at least one fixed resistor R1, one adjustable resistor R2, two branch switches K1 and K2, and optionally one bypass switch K in the power supply circuit thereof.

[0062] In the power supply circuit of the same coil disc 3, the fixed resistor R1 and the adjustable resistor R2 are connected in parallel, and the coil disc 3 can be connected in series with the energy storage capacitor through the fixed resistor R1 or the adjustable resistor R2, respectively.

[0063] In the power supply circuit of the same coil disc 3, the branch switch K1 is connected in series with the fixed resistor R1 to control whether the energy storage capacitor discharges to the coil disc 3 through the branch with the fixed resistor R1, and the branch switch K2 is connected in series with the adjustable resistor R2 to control whether the energy storage capacitor discharges to the coil disc 3 through the branch with the adjustable resistor R2.

[0064] In the power supply circuit of the same coil disc 3, if the bypass switch K is equipped, the bypass switch K is connected in parallel with the fixed resistor R1 and the adjustable resistor R2, and the bypass switch K is also connected in parallel with the branch switches K1 and K2 to control whether the energy storage capacitor discharges to the coil disc 3 through the branch with the bypass switch K.

[0065] In addition, the coil disc 3 used in the vacuum interrupter of the three-phase circuit breaker K Z may also optionally adopt the equipped scheme of the power supply circuit of the coil disc 3 in the phase-controlled switch K a , K b and K c .

[0066] In the prior art, the fixed resistor R1, the adjustable resistor R2, the branch switches K1 and K2, and the branches thereof together constitute a buffer assembly, and the branch switches K1 and K2 cannot be in the on state at the same time. That is, when the branch switch K1 is in the on state, the branch switch K2 is in the off state, and the energy storage capacitor supplies power to the coil disc 3 through the branch with the fixed resistor R1; when the branch switch K2 is in the on state, the branch switch K1 is in the off state, and the energy storage capacitor supplies power to the coil disc 3 through the branch with the adjustable resistor R2.

[0067] The branch switches K1 and K2 equipped with the buffer assembly, and the three-phase circuit breaker K Z have the following closing and opening processes:

[0068] During the closing process, the branch switch K2 in series with the upper coil disc 3 is in the on state, and the adjustable resistance R2 in series with the branch switch K2 is in the process of increasing its resistance value, while the branch switch K1 in series with the lower coil disc 3 is in the on state. In addition, the initial resistance value of the adjustable resistance R2 in series with the branch switch K2 is greater than the resistance value of the fixed resistance R1 in series with the branch switch K1. The initial resistance value of the adjustable resistance R2 refers to the resistance value of the adjustable resistance R2 when the branch in which the adjustable resistance R2 is located is just in the on state, that is, the resistance value of the adjustable resistance R2 when the branch switch K2 in series with the adjustable resistance R2 is just closed to form a path. In this way, the area between the repulsion disc 2 and the coil disc 3 arranged above and below the repulsion disc 2 is formed with repulsive magnetic fields, and with the increase of the resistance value of the adjustable resistance R2 in series with the upper coil disc 3, the repulsive magnetic field in the area above the repulsion disc 2 decays, the repulsion disc 2 moves upward and finally contacts the upper coil disc 3, and the movable contact of the vacuum interrupter moves upward and contacts the fixed contact to form a path. That is, the vacuum interrupter is in the on state, and the closing operation is completed.

[0069] During the opening process, the branch switch K2 in series with the lower coil disc 3 is in the on state, and the adjustable resistance R2 in series with the branch switch K2 is in the process of increasing its resistance value, while the branch switch K1 in series with the upper coil disc 3 is in the on state. In addition, the initial resistance value of the adjustable resistance R2 in series with the branch switch K2 is greater than the resistance value of the fixed resistance R1 in series with the branch switch K1. The initial resistance value of the adjustable resistance R2 refers to the resistance value of the adjustable resistance R2 when the branch in which the adjustable resistance R2 is located is just in the on state, that is, the resistance value of the adjustable resistance R2 when the branch switch K2 in series with the adjustable resistance R2 is just closed to form a path. In this way, the area between the repulsion disc 2 and the coil disc 3 arranged above and below the repulsion disc 2 is formed with repulsive magnetic fields, and with the increase of the resistance value of the adjustable resistance R2 in series with the lower coil disc 3, the repulsive magnetic field in the area below the repulsion disc 2 decays, the repulsion disc 2 moves downward and finally contacts the lower coil disc 3, and the movable contact of the vacuum interrupter moves downward and separates from the fixed contact to form an open circuit. That is, the vacuum interrupter is in the off state, and the opening operation is completed.

[0070] During the closing and opening processes of the above-mentioned vacuum interrupter, the repulsive magnetic field formed in the area between the repulsion disc 2 and the coil disc 3 to which the repulsion disc 2 moves is in a state of gradual decay until the two contact each other. Therefore, under the repulsive force of the two, the area becomes a buffer area for the movement of the repulsion disc 2, avoiding the repulsion disc 2 from directly colliding with the coil disc 3 in a hard collision manner. That is, the force when the two contact each other is reduced. Again, due to the reduction of the force when the two contact each other, the noise generated when the two contact each other is reduced, thereby reducing the interference to the collection of sound signals in the vicinity.

[0071] Switching process of the reactive device C in the power grid system Z is as follows:

[0072] The reactive device CZ When put into the power grid system, first close the three-phase circuit breaker K Z and the phase-controlled switch K b , then make the phase-controlled switch K a and K c complete closing in the respective preset closing phase angle range. In this process, the silicon stacks TL in the A-phase line and the C-phase line suppress the inrush current. During this period, if overvoltage occurs, it is shunted by the energy-absorbing component ZGD-B, which converts the electrical energy flowing through it into heat energy for consumption to suppress overvoltage.

[0073] When the reactive device C Z needs to be withdrawn from the power grid system, first make the phase-controlled switch K a and K c complete opening in the respective preset opening phase angle range, then wait until the phase-controlled switch K a and K c both complete opening to the preset time interval, and then make the three-phase circuit breaker K Z and the phase-controlled switch K b open. In this process, if overvoltage occurs, it is shunted by the energy-absorbing component ZGD-B, which converts the electrical energy flowing through it into heat energy for consumption to suppress overvoltage.

[0074] Please refer to Figure 4 , in which:

[0075] R1 and R2 respectively represent a fixed resistor and an adjustable resistor;

[0076] K F1 , K H2 , K F2 and K H1 all represent branch switches.

[0077] The present application improves the repulsion mechanism and buffer component of the vacuum arc-extinguishing chamber on the basis of the prior art, as follows:

[0078] The same pair of coil plates 3 (i.e., two coil plates 3 facing the same direction of the two plate surfaces of the same repulsion plate 2, and the two coil plates 3 jointly act on the repulsion plate 2) are connected in parallel with each other;

[0079] The same set of resistors (i.e., one fixed resistor R1 and one adjustable resistor R2) are connected in parallel with each other;

[0080] The two coil plates 3 in the same pair are respectively connected in series with the fixed resistor R1 and the adjustable resistor R2 in the same set of resistors, thereby forming four series branch circuits, and the branch switches K F1 , K H2 , K F2 and K H1Respectively, single connection in the four series branches, and each series branch only by a branch switch K F1 , K H2 , K F2 Or K H1 Control its on-off.

[0081] Further, the four series branches are respectively:

[0082] The coil disc 3 and the fixed resistor R1 in the direction of the disc surface of the repulsion disc 2 form a series branch, and the branch switch K F1 Is connected between the coil disc 3 and the fixed resistor R1 in the series branch, and the branch switch K F1 Only controls the on-off of the series branch;

[0083] The coil disc 3 and the adjustable resistor R2 in the direction of the disc surface of the repulsion disc 2 form a series branch, and the branch switch K H2 Is connected between the coil disc 3 and the adjustable resistor R2 in the series branch, and the branch switch K H2 Only controls the on-off of the series branch;

[0084] The coil disc 3 and the adjustable resistor R2 in the direction of the disc surface of the repulsion disc 2 form a series branch, and the branch switch K F2 Is connected between the coil disc 3 and the adjustable resistor R2 in the series branch, and the branch switch K F2 Only controls the on-off of the series branch;

[0085] The coil disc 3 and the fixed resistor R1 in the direction of the disc surface of the repulsion disc 2 form a series branch, and the branch switch K H1 Is connected between the coil disc 3 and the fixed resistor R1 in the series branch, and the branch switch K H1 Only controls the on-off of the series branch.

[0086] In the closing and opening process of the vacuum arc-extinguishing chamber, the coil disc 3 and the adjustable resistor R2 in the series branch close to the repulsion disc 2 are in the on state, and the resistance value of the adjustable resistor R2 increases, while the coil disc 3 and the fixed resistor R1 in the series branch away from the repulsion disc 2 are in the on state, and the other two series branches are in the off state.

[0087] The application improves the inrush current and overvoltage protection device on the basis of the prior art, that is, the improved repulsion mechanism and buffer assembly of the application are applied to the inrush current and overvoltage protection device of the prior art, as follows:

[0088] The phase-controlled switch K a , K b And Kc The repulsion mechanism and buffer assembly used for opening and closing the vacuum interrupter are replaced with the improved repulsion mechanism and buffer assembly of this invention.

[0089] In addition, three-phase circuit breaker K Z If the vacuum interrupter in the circuit is driven to open or close by a repulsion mechanism, then the vacuum interrupter may or may not adopt the repulsion mechanism and buffer assembly improved in this invention.

[0090] The improved repulsion mechanism and buffer assembly of this invention drive the opening and closing of the vacuum interrupter in the device, so that the two coil disks equipped with the same repulsion disk can share the same power supply circuit. Furthermore, the buffer assembly equipped with the power supply circuit can control the establishment and change of the magnetic field of the two coil disks, thus optimizing the configuration number of buffer assemblies in the prior art. This not only helps to reduce the production cost of the device, but also helps to reduce the space of the device and promote the miniaturization of the device.

[0091] Example 1: Based on the improved repulsion mechanism and buffer assembly of the present invention, taking a vacuum interrupter chamber equipped with a repulsion disk 2 as an example, the details are as follows:

[0092] Repulsion disk 2 is equipped with two coil disks 3;

[0093] The two surfaces of the repulsion disk 2 face upwards and downwards, and the two coil disks 3 are respectively set in the directions facing the two surfaces of the repulsion disk 2, that is, the repulsion disk 2 is located between the two coil disks 3;

[0094] The two coil disks 3 are connected in parallel and share the same power supply circuit;

[0095] The power supply circuit contains energy storage capacitors that provide power to the two coil disks 3, that is, the two coil disks 3 are connected in series with the energy storage capacitors respectively;

[0096] The upper coil disk 3 is connected in series with the fixed resistor R1 to form a series branch, and the branch switch K F1 It is connected in series between the two to control the on / off state of the series branch;

[0097] The upper coil disk 3 is connected in series with the adjustable resistor R2 to form a series branch, and the branch switch K H2 It is connected in series between the two to control the on / off state of the series branch;

[0098] The lower coil disk 3 is connected in series with the adjustable resistor R2 to form a series branch, and the branch switch K F2 It is connected in series between the two to control the on / off state of the series branch;

[0099] The lower coil disk 3 is connected in series with the fixed resistor R1 to form a series branch, and the branch switch K H1a branch switch connected in series between the two to control the on-off of the series branch;

[0100] Of the four series branches, two are connected in series between the upper coil disc 3 and the energy storage capacitor, and the other two are connected in series between the lower coil disc 3 and the energy storage capacitor, and each branch switch K F1 , K H2 , K F2 or K H1 controls the on-off of the series branch in which it is located.

[0101] During the closing process of the vacuum interrupter, the branch switch K H2 is closed, the series branch in which the upper coil disc 3 and the adjustable resistor R2 connected in series is in the on state, and the resistance value of the adjustable resistor R2 is increased by the preset control command; the branch switch K H1 is also closed, the series branch in which the lower coil disc 3 and the fixed resistor R1 connected in series is in the on state; the branch switches K F1 and K F2 are opened, so that the series branches in which they are located are in the off state.

[0102] In this way, the electrical energy of the energy storage capacitor is transmitted to the upper coil disc 3 through the adjustable resistor R2, so that the upper coil disc 3 is powered to establish a magnetic field that decays; and the electrical energy of the energy storage capacitor is also transmitted to the lower coil disc 3 through the fixed resistor R1, so that the lower coil disc 3 is powered to establish a stable magnetic field.

[0103] During the opening process of the vacuum interrupter, the branch switch K F1 is closed, the series branch in which the upper coil disc 3 and the fixed resistor R1 connected in series is in the on state; the branch switch K F2 is also closed, the series branch in which the lower coil disc 3 and the adjustable resistor R2 connected in series is in the on state, and the resistance value of the adjustable resistor R2 is increased by the preset control command; the branch switches K H2 and K H1 are opened, so that the series branches in which they are located are in the off state.

[0104] In this way, the electrical energy of the energy storage capacitor is transmitted to the upper coil disc 3 through the fixed resistor R1, so that the upper coil disc 3 is powered to establish a stable magnetic field; and the electrical energy of the energy storage capacitor is also transmitted to the lower coil disc 3 through the adjustable resistor R2, so that the lower coil disc 3 is powered to establish a magnetic field that decays.

[0105] Preferably, the resistance value of the adjustable resistor R2 when it is in the on state is greater than the resistance value of the fixed resistor R1 during the closing and opening processes of the vacuum interrupter.

[0106] Because the resistance of the adjustable resistor R2 connected to the coil 3 closest to the repulsion disk 2 when it is just connected is greater than the resistance of the fixed resistor R1 connected to the coil 3 furthest from the repulsion disk 2, and the resistance of the adjustable resistor R2 increases, it means that when the coil 3 closest to the repulsion disk 2 is energized, the current flowing through it tends to decrease; while when the coil 3 furthest from the repulsion disk 2 is energized, the current flowing through it remains relatively stable. Therefore, the repulsive magnetic field between the repulsion disk 2 and the nearby coil 3 is always less than the repulsive magnetic field between the repulsion disk 2 and the furthest coil 3 from the moment it is established until it disappears, and the difference between these two repulsive magnetic fields increases. This ensures the effective operation of the repulsion disk 2, enabling it to drive the vacuum interrupter to perform effective closing and opening actions.

[0107] Preferably, a pull rod 1 is installed at the outer end of the moving rod of the vacuum interrupter, and a repulsive disk 2 is installed on the rod body of the pull rod 1. The coil disk 3 does not contact the pull rod 1. The change in the magnetic field between the repulsive disk 2 and the coil disk 3 drives the pull rod 1 to move, thereby causing the vacuum interrupter to perform closing and opening actions. That is, when the vacuum interrupter needs to close, both coil disks 3 are energized. A repulsive magnetic field is formed in the area between the repulsive disk 2 and the coil disks 3 above and below it. As the resistance value of the adjustable resistor R2 connected in series with the upper coil disk 3 increases, the repulsive magnetic field in the area above the repulsive disk 2 decreases. The repulsive disk 2 moves upward and eventually contacts the upper coil disk 3. During this process, the pull rod 1 of the vacuum interrupter moves upward, causing the moving rod contact of the vacuum interrupter to move upward and contact the stationary rod contact to form a circuit. The vacuum interrupter completes the closing action. After the closing action is completed, the two coil disks 3 are de-energized, causing the repulsive disk 2 to close. When the vacuum interrupter needs to be tripped, a repulsive magnetic field is formed in the area between the repulsive disk 2 and the coil disks 3 above and below it. As the resistance of the adjustable resistor R2 connected in series with the lower coil disk 3 increases, the repulsive magnetic field in the area below the repulsive disk 2 decreases. The repulsive disk 2 moves down and eventually contacts the lower coil disk 3. During this process, the pull rod 1 of the vacuum interrupter moves down, causing the moving rod contact of the vacuum interrupter to move down and separate from the stationary rod contact to form an open circuit. The vacuum interrupter completes the tripping. After the tripping is completed, the two coil disks 3 are de-energized, causing the repulsive magnetic field to disappear.

[0108] The strength of the magnetic field of coil disk 3 is controlled by a buffer assembly, thereby adjusting the repulsive magnetic field between repulsive disk 2 and coil disk 3 to drive the repulsive disk to operate, thus realizing the opening and closing action of the vacuum interrupter. Since there is a repulsive force between repulsive disk 2 and coil disk 3 before they come into contact, it cancels out part of the collision force when they come into contact. That is, the area formed between repulsive disk 2 and coil disk 3 can act as a buffer zone, avoiding direct hard collisions between them and reducing the noise generated when they come into contact.

[0109] Preferably, the repulsion disc 2 adopts a permanent magnet design, and the coil disc 3 adds a material that can be adsorbed by the repulsion disc.

[0110] Through the contact between the repulsion disc 2 and the coil disc 3, the two are attracted together after contact. In this way, the iron core and the permanent magnet used in the prior art to maintain the closed state of the vacuum arc-extinguishing chamber can be directly cancelled, saving production costs and reducing the space occupied by this part, which is conducive to the miniaturization design of the device.

[0111] Example two, based on the technical solution of example one, taking a vacuum arc-extinguishing chamber equipped with multiple repulsion discs 2 as an example, the specific implementation is as follows:

[0112] Each repulsion disc 2 is separately equipped with two coil discs 3, and each repulsion disc 2 is configured according to the technical solution of example one.

[0113] Example three, based on the technical solution of any of the above examples, this embodiment gives a further improved scheme of the adjustable resistance R2, which is as follows:

[0114] The adjustable resistance R2 can be designed based on the principle of a slide rheostat, that is, the adjustable resistance R2 includes a resistance piece one 4 and a slide piece 5, and the resistance value of the adjustable resistance R2 is changed by the slide piece 5 sliding along the surface of the resistance piece one 4. Among them, the resistance piece one 4 is equivalent to the resistance wire of the slide rheostat, and the slide piece 5 is equivalent to the slide piece in the slide rheostat, and the slide piece 5 can be equipped with a driving device (such as an electrically controlled linear guide rail) for driving the slide piece 5 to slide along the surface of the resistance piece one 4.

[0115] Preferably, one end of the resistance piece one 4 and the slide piece 5 are respectively provided with a terminal post, and the two terminal posts are respectively used as the input and output terminals of the adjustable resistance R2, so that the adjustable resistance R2 is connected in series between the coil disc 3 and the energy storage capacitor.

[0116] Preferably, the resistance piece one 4 and the slide piece 5 are respectively provided with a terminal post, and the terminal post on the slide piece 5 is connected to the energy storage capacitor through a wire, and the terminal posts at both ends of the resistance piece one 4 correspond to the two coil discs 3 equipped with the same repulsion disc 2, and are respectively connected to the corresponding coil disc 3 through a wire. Among them, the terminal post on one end of the resistance piece one 4 and the terminal post on the slide piece 5 are respectively used as the input and output terminals of the adjustable resistance R2, so that the adjustable resistance R2 is connected in series between one of the coil discs 3 equipped with the same repulsion disc 2 and the energy storage capacitor; the terminal post on the other end of the resistance piece one 4 and the terminal post on the slide piece 5 are respectively used as the input and output terminals of the adjustable resistance R2, so that the adjustable resistance R2 is connected in series between the other coil disc 3 equipped with the same repulsion disc 2 and the energy storage capacitor.

[0117] Example four, please refer to Figure 5 and Figure 7, based on the two ends of the resistor one 4 and the slide 5, the slide 5 is provided with a terminal, the terminal of the slide 5 is connected to the energy storage capacitor through a wire, and the terminals of the resistor one 4 correspond to the two coil discs 3 of the same repulsion disc 2, and are respectively connected to the corresponding coil disc 3 through a wire. The embodiment gives a further improved scheme of the adjustable resistor R2, as follows:

[0118] The lower pull rod 1 installed at the outer end of the moving rod of the vacuum arc-extinguishing chamber is provided with an embedding groove, and the resistor one 4 is embedded in the embedding groove. The surface of the resistor one 4 is outwardly matched with the slide 5, so that the resistor one 4 can move with the lower pull rod 1. In addition, the slide 5 is arranged on the surface of the resistor one 4, and the spatial position of the slide 5 remains stationary relative to the static contact of the vacuum arc-extinguishing chamber. Further, when the lower pull rod 1 drives the resistor one 4 to move, the contact position between the resistor one 4 and the slide 5 changes, so that the resistance of the adjustable resistor R2 changes.

[0119] During the closing process of the vacuum arc-extinguishing chamber, the lower pull rod 1 moves upwards, the coil disc 3 above the repulsion disc 2 is connected to the energy storage capacitor through the adjustable resistor R2, and the coil disc 3 is powered to establish a magnetic field. The resistance of the adjustable resistor R2 increases.

[0120] During the opening process of the vacuum arc-extinguishing chamber, the lower pull rod 1 moves downwards, the coil disc 3 below the repulsion disc 2 is connected to the energy storage capacitor through the adjustable resistor R2, and the coil disc 3 is powered to establish a magnetic field. The resistance of the adjustable resistor R2 increases.

[0121] Since the resistor one 4 is embedded in the rod body of the lower pull rod 1, it is not necessary to reserve a mounting position for the resistor one 4 outside the lower pull rod 1, so that the space is saved, thereby further reducing the occupation of the external space by the buffer assembly.

[0122] In addition, the resistor one 4 of the adjustable resistor R2 in the buffer assembly is installed in the lower pull rod 1, so that the resistor one 4 adjusts the resistance of the adjustable resistor R2 when it moves with the lower pull rod 1, and it is not necessary to adjust the resistance change of the resistor one 4 through the setting of additional tools and energy control components.

[0123] Example five, please refer to Figure 6 and Figure 8 , based on the technical scheme of any of the above embodiments, the embodiment gives a further improved scheme of the fixed resistor R1, as follows:

[0124] The fixed resistor R1 comprises a resistor two 6, and each end of the resistor two 6 is provided with a terminal. The terminals are respectively used as the inlet and outlet terminals of the fixed resistor R1, so that the fixed resistor R1 is connected in series between the coil disc 3 and the energy storage capacitor.

[0125] Preferably, a recess is formed on the rod body of the lower pull rod 1 installed at the outer end of the moving rod of the vacuum interrupter, and the resistor 6 is embedded in the recess.

[0126] Since the resistor 6 is embedded in the rod body of the lower pull rod 1, the installation position of the resistor 6 does not need to be reserved in the space outside the lower pull rod 1, so that the space is saved, thereby further reducing the occupation of the external space by the buffer assembly.

[0127] In the sixth embodiment, based on the technical solutions of any of the above embodiments, the technical solutions of a reactive device switching overvoltage protection device are provided, and the technical solutions are further improved based on the inrush current and overvoltage protection device in the prior art, and specifically in that:

[0128] The vacuum interrupter of the phase-controlled switch K a , K b and K c adopts the repulsion mechanism and the buffer assembly improved by the application to drive the closing and opening operations.

[0129] Preferably, the vacuum interrupter of the three-phase circuit breaker K Z also adopts the repulsion mechanism and the buffer assembly improved by the application to drive the closing and opening operations.

[0130] The phase-controlled switch K a , K b and K c are each connected with a corresponding phase control device D a , D b or D c , and the phase control device D a , D b and D c each has a silicon stack TL and an energy absorption assembly ZGD-B built therein, and any phase-controlled switch K a , K b or K c and the energy absorption assembly ZGD-B, the silicon stack TL and the corresponding phase control device D a , D b or D c are connected in parallel with each other, and when the three-phase circuit breaker K Z is in the closing state and any phase-controlled switch K a , K b or K c is in the opening state, the current passes through the silicon stack TL connected in parallel with the phase-controlled switch K a , K b or K c , and the current is suppressed by the silicon stack TL.

[0131] In addition, the phase-controlled switch K a , Kb and K c Each of the single-phase breakers K a , D b or D c is connected with a corresponding phase control device D a , D b or D c , respectively, and each of the phase control devices D a , D b or D c is internally provided with a silicon stack TL and an energy absorbing component ZGD-B, and any one of the phase control switches K a , K b or K c is connected in parallel with the energy absorbing component ZGD-B and the silicon stack TL of the corresponding phase control device D Z When any one of the phase control switches K a , K b or K c is in the open state and the voltage across the phase control switch K a , K b or K c and the silicon stack TL connected in parallel therewith is too high to satisfy the conduction condition of the energy absorbing component ZGD-B connected in parallel therewith, the current is shunted to the energy absorbing component ZGD-B and consumed by the energy absorbing component ZGD-B, thereby suppressing overvoltage.

[0132] In the present embodiment, the repulsion mechanism and the buffer component improved by the present application are applied to avoid hard collision between the repulsion disc 2 and the coil disc 3 by using repulsive magnetic field, thereby reducing the deformation and wear condition between the repulsion disc 2 and the coil disc 3, so that the reactive device switching overvoltage protection device provided in the present embodiment can be applied to the power grid system requiring frequent switching of the reactive device C Z .

[0133] Based on the above content and the drawings, those skilled in the art can understand and implement the present application. Furthermore, any non-creative modification of the present application made by those skilled in the art without creative labor still falls within the protection scope of the present application.

Claims

1. A repulsion mechanism, comprising a pull-down rod (1) installed at the outer end of a moving rod of a vacuum interrupter and a repulsion mechanism driving the vacuum interrupter to perform closing and opening actions, the repulsion mechanism comprising at least one repulsion disc (2), each of the two disc surfaces of the same repulsion disc (2) being equipped with a coil disc (3), characterized in that, The two coil plates (3) are connected in parallel and share the same power supply circuit, which is equipped with a buffer assembly containing: a fixed resistor and an adjustable resistor, both of which are connected in parallel and are connected in series with the two coil plates (3) respectively to form four series branches, and each series branch is connected with a branch switch to control the on-off of the series branch. During the closing and opening process of the vacuum interrupter, the coil plate (3) close to the repulsion plate (2) and its series adjustable resistor in the series branch are in the on state, and the resistance value of the adjustable resistor increases, while the coil plate (3) away from the repulsion plate (2) and its series fixed resistor in the series branch are in the on state, and the remaining series branches are in the off state. That is, during the closing process, the lower pull rod (1) moves up, the coil plate (3) above the repulsion plate (2) is conducted through the adjustable resistor and establishes a magnetic field, and during the opening process, the lower pull rod (1) moves down, the coil plate (3) below the repulsion plate (2) is conducted through the adjustable resistor and establishes a magnetic field; During the closing and opening process, the resistance value of the adjustable resistor increases.

2. The repulsion mechanism according to claim 1, characterized in that: When the coil plate (3) and its series fixed resistor in the series branch are in the on state, the coil plate (3) is powered to establish a stable magnetic field; When the coil plate (3) and its series adjustable resistor in the series branch are in the on state, the coil plate (3) is powered to establish a magnetic field that decays.

3. The repulsion mechanism according to claim 1 or 2, characterized in that: During the closing and opening process of the vacuum interrupter, the resistance value of the adjustable resistor when it is just on is greater than the resistance value of the fixed resistor.

4. The repulsion mechanism according to claim 1, characterized in that: The repulsion plate (2) is installed on the rod body of the lower pull rod (1), and the coil plate (3) does not contact the lower pull rod (1), and the lower pull rod (1) is moved by the change of the magnetic field between the repulsion plate (2) and the coil plate (3) to make the vacuum interrupter close and open.

5. The repulsion mechanism according to claim 1, characterized in that: The adjustable resistor contains a resistor piece one (4) and a slide piece (5), and the resistance value of the adjustable resistor is changed by sliding the slide piece (5) along the surface of the resistor piece one (4).

6. The repulsion mechanism according to claim 5, characterized in that: One end of the resistor piece one (4) and the slide piece (5) are each provided with a terminal post, and the two terminal posts are respectively connected as the input and output terminals of the adjustable resistor and connected between the coil plate (3) and the energy storage capacitor of the power supply circuit.

7. The repulsion mechanism according to claim 5, characterized in that: The two ends of the resistor piece one (4) and the slide piece (5) are each provided with a terminal post, the terminal post on the slide piece (5) is connected to the energy storage capacitor of the power supply circuit through a wire, and the terminal posts at both ends of the resistor piece one (4) correspond to the two coil plates (3) of the same repulsion plate (2), and are respectively connected to the corresponding coil plate (3) through a wire.

8. The repulsion mechanism according to claim 1, characterized in that: The fixed resistor comprises a resistor element two (6), and two terminals of the resistor element two (6) are respectively provided with a terminal post, which is connected to the coil panel (3) and the energy storage capacitor of the power supply circuit as the input and output terminals of the fixed resistor.

9. A repulsion mechanism according to claim 7 or 8, characterised in that, The movable rod of the vacuum arc-extinguishing chamber is provided with a pull-down rod (1) at the outer end, and a slot is formed in the rod body of the pull-down rod (1). The slot is used for embedding the resistor element one (4). Or, the slot is used for embedding the resistor element two (6). Or, the slot has two types, one of which is used for embedding the resistor element one (4), and the other of which is used for embedding the resistor element two (6).

10. A reactive device switching overvoltage protection device, comprising a three-phase circuit breaker, a phase control switch is connected to each phase outgoing terminal of the three-phase circuit breaker, a silicon stack and an energy absorption assembly are connected in parallel to the phase control switch, and the silicon stack and the energy absorption assembly are connected in parallel, and a reactive device is connected to the outgoing terminal of the phase control switch, characterized in that: The vacuum arc-extinguishing chamber of the phase-controlled switch is driven by the repulsion mechanism of claim 1 to perform the closing and opening operations.

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