CN111431158B

CN111431158B - Overvoltage combined suppression system and device of vacuum circuit breaker

Info

Publication number: CN111431158B
Application number: CN202010328557.3A
Authority: CN
Inventors: 刘国特
Original assignee: Foshan University
Current assignee: Foshan University
Priority date: 2020-04-23
Filing date: 2020-04-23
Publication date: 2021-11-05
Anticipated expiration: 2040-04-23
Also published as: CN111431158A

Abstract

The invention provides an overvoltage combined suppression system and device of a vacuum circuit breaker, which comprise a 10kV bus, a reactor group connected in parallel, a station transformer, a first class voltage measuring device, a lightning arrester, a second class voltage measuring device and a circuit breaker, wherein the reactor group is configured to be connected with the 10kV bus in parallel to form a first branch circuit, the second class voltage measuring device is configured to measure the first branch circuit, and the circuit breaker is connected in series; the station transformer is configured to be connected with a 10kV bus in parallel to form a second branch, the second type voltage measuring device is configured to measure the voltage of the first type on the second branch, the first type voltage measuring device is configured to be connected with the 10kV bus in parallel to form a third branch, and a fuse is connected in series on the third branch; the lightning arrester is configured to be connected to a 10kV bus at one end and to a ground at the other end. The invention can effectively inhibit the overvoltage amplitude of the system by adopting the protection mode of the reactor and the resistor and installing the zinc oxide lightning arrester in parallel.

Description

Overvoltage combined suppression system and device of vacuum circuit breaker

Technical Field

The invention relates to the technical field of vacuum circuit breakers, in particular to an overvoltage combined suppression system and device of a vacuum circuit breaker.

Background

People's requirement to electric power quality is higher and higher, and when reactive power was too much, the voltage of one of the important index of electric energy quality will rise, has reduced electrical equipment availability factor. Because the load of the power system changes constantly, the power grid is required to frequently switch reactive power equipment such as a shunt reactor and the like, and the voltage amplitude is ensured to be within a normal range. The vacuum circuit breaker has stronger arc extinguishing capability and insulating property, and is widely applied to frequent switching of the parallel reactor operation. However, with the rapid development of power grids, short-circuit faults caused by insulation breakdown of equipment due to overvoltage caused by opening and closing of a shunt reactor by a vacuum circuit breaker have seriously influenced the safe and stable operation of the power grids. Therefore, the overvoltage suppression device for the switching-off parallel reactor of the vacuum circuit breaker is developed, and the application significance is very important.

For example, CN106710833A prior art discloses a resistor type reactor and a manufacturing method thereof, the resistor structure is single and mainly includes a braided structure and a sheet structure, and the resistor and the reactor are installed separately, which occupies a large area and requires a large installation workload. In addition, due to the structural limitation of the resistor, the resistance of the resistor to fault current, wind and earthquake is poor.

In addition, in the conventional design, the neutral point is not grounded or is not grounded well, so that the phenomenon of re-ignition is easily caused.

The invention is made in order to solve the problems that the resistor is easy to break down, the capacitor is resistant to voltage difference, the overvoltage cannot be inhibited, the overvoltage cannot be protected and the like in the field.

Disclosure of Invention

The invention aims to provide an overvoltage combination suppression system and device of a vacuum circuit breaker, aiming at the defects in the switching process of the conventional vacuum circuit breaker.

In order to overcome the defects of the prior art, the invention adopts the following technical scheme:

an overvoltage combination suppression system and device of a vacuum circuit breaker comprise a 10kV bus, a reactor group, a station transformer, a first class voltage measuring device, a lightning arrester, a second class voltage measuring device and a circuit breaker, wherein the reactor group is connected in parallel with the 10kV bus to form a first branch circuit;

the station transformer is configured to be connected in parallel with the 10kV bus to form a second branch;

the first type of voltage measuring device is configured to be connected with the 10kV bus in parallel to form a third branch, and a fuse is connected to the third branch in series;

the lightning arrester is configured to be connected with the 10kV bus at one end and connected with a ground wire at the other end;

the second class of voltage measuring devices comprises a first voltage measuring device and a second voltage measuring device, the first voltage measuring device is configured to measure on the first branch, and the second voltage measuring device is configured to measure on the second branch;

the circuit breaker is connected in series on the first branch and the second branch and is used for switching on and switching off power supply lines of the first branch and the second branch.

Optionally, the second branch is configured to be provided with a connection point a and a connection point b;

the a connection point is arranged at the near side of the output end of the circuit breaker, and the lightning arrester is installed at the a connection point;

the b connection point is arranged between the first voltage measuring device and the station transformer, and the lightning arrester and the RC absorber are installed at the b connection point.

Optionally, the 10kV bus is further configured to connect the current-limiting reactor and the main transformer in parallel to form a fourth branch.

Optionally, the first branch is configured to be provided with a c connection point and a d connection point;

the c-connection point is arranged near the output end of the circuit breaker;

the d-connection point is provided between the second voltage measuring device and the reactor, and the arrester is installed at the d-connection point.

Optionally, the reactor includes a plurality of electric capacity, a pair of PCB board, a pair of electric capacity connecting piece, electric capacity insulation head and electric capacity insulating cylinder, and is a pair of PCB board parallel arrangement, each the electric capacity sets up a pair of between the PCB board, each the electric capacity is with a pair of the length direction of PCB board is placed perpendicularly, and is a pair of the electric capacity connecting piece is with a pair of the both ends of PCB board are connected, electric capacity connecting piece journey I shape just be equipped with a plurality of connecting hole on the electric capacity connecting piece, electric capacity insulation head pass through the screw with the electric capacity connecting piece is connected, and is a pair of the PCB board nestification in the electric capacity insulating cylinder.

Optionally, the capacitor insulating cylinder is cast in a sealing manner, a plurality of umbrella skirts are nested outside the insulating cylinder, and each umbrella skirt and the insulating cylinder are coaxially arranged.

Optionally, a plurality of through grooves are formed in one side plate of the PCB, the through grooves are parallel to the extending direction of the PCB, and the through grooves are arranged at equal intervals along the extending direction of the PCB.

The beneficial effects obtained by the invention are as follows:

1. the overvoltage amplitude of the system can be effectively inhibited by adopting a protection mode of installing zinc oxide arresters in parallel;

2. the oscillation frequency of the overvoltage and the amplitude of the restrike overvoltage frequency overvoltage can be reduced by adopting the arrangement of the RC resistance container; the resistor R can accelerate the oscillation attenuation process, so that the overvoltage is quickly reduced;

3. the zinc oxide lightning arrester is used as common overvoltage suppression equipment, and overvoltage energy is released through the nonlinear resistor to achieve overvoltage suppression;

4. by adopting the matching use of the reactor and the resistor, the overvoltage of the circuit breaker in the switching process is effectively ensured, and the phenomena of easy breakdown and re-ignition are overcome.

Drawings

The invention will be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the embodiments. Like reference numerals designate corresponding parts throughout the different views.

FIG. 1 is a schematic view of the system structure of the restraining device

Fig. 2 is a schematic structural diagram of the field experiment.

Fig. 3 is a single-phase equivalent circuit diagram.

Fig. 4 is a graph of reactor overvoltage.

Fig. 5 is a graph of overvoltage at a station transformer.

Fig. 6 is a graph of the paraampere curve of the arrester.

Fig. 7 is a graph showing the influence of the installation position of the surge arrester on the overvoltage of the reactor.

Fig. 8 is a graph showing the influence of the installation position of the lightning arrester on the overvoltage of the station transformer.

Fig. 9 is a waveform diagram of overvoltage at the reactor.

Fig. 10 is a voltage waveform diagram of the installation of the lightning arrester at the b connection point and the d connection point.

Fig. 11 is a waveform diagram of overvoltage at the head end of the reactor.

Fig. 12 is a waveform diagram of the station transformer.

Fig. 13 is a graph of overvoltage at the reactor head end.

Fig. 14 is a graph of the overvoltage at the head end of the station transformer.

FIG. 15 is a schematic view of the reactor

Fig. 16 is a schematic structural view of the connector.

Fig. 17 is a schematic structural view of the PCB board.

Fig. 18 is a schematic structural view of the insulation tube sealing head. .

Fig. 19 is a schematic structural view of the reactance insulating cylinder.

Fig. 20 is a schematic view of the overall structure of the reactor.

Fig. 21 is a schematic view of a structure of a part of the resistor.

Fig. 22 is a schematic structural view of the insulation tube end socket.

Fig. 23 is a schematic structural view of the resistance connecting member.

Fig. 24 is a schematic structural view of the electrical resistance insulation cylinder.

Fig. 25 is a schematic view of the overall structure of the resistor.

Description of reference numerals: 1-a PCB board; 2-a capacitor connecting rod; 3-capacitance; 4-capacitor insulation end socket; 5-a capacitive connection; 6-side plate; 7-standing the plate; 8-a resistive connecting rod; 9-a pull rod; 10-a half round table; 11-a capacitive insulating cylinder; 12-a resistive cavity; 13-a resistive connection; 14-a resistor cylinder; 15-insulating cylinder sealing head; 16-a connection station; 17-a circular ring; 18-a fixed plate; 19-a resistive insulating cylinder; 20-umbrella skirt; 21-through groove.

Detailed Description

In order to make the objects and advantages of the present invention more apparent, the present invention will be further described in detail with reference to the following embodiments; it should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Other systems, methods, and/or features of the present embodiments will become apparent to those skilled in the art upon review of the following detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description, be within the scope of the invention, and be protected by the accompanying claims. Additional features of the disclosed embodiments are described in, and will be apparent from, the detailed description that follows.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by the terms "upper" and "lower" and "left" and "right" etc., it is only for convenience of description and simplification of the description based on the orientation or positional relationship shown in the drawings, but it is not indicated or implied that the device or assembly referred to must have a specific orientation.

The first embodiment is as follows: an overvoltage combination suppression system and device of a vacuum circuit breaker comprise a 10kV bus, a reactor group, a station transformer, a first class voltage measuring device, a lightning arrester, a second class voltage measuring device and a circuit breaker, wherein the reactor group is connected in parallel with the 10kV bus to form a first branch, the second class voltage measuring device is configured to measure the first branch, and the circuit breaker is connected in series; the station transformer is configured to be connected with the 10kV bus in parallel to form a second branch, and a second type voltage measuring device is configured to measure on the second branch; the first type of voltage measuring device is configured to be connected with the 10kV bus in parallel to form a third branch, and a fuse is connected to the third branch in series; the lightning arrester is configured to be connected with the 10kV bus at one end and connected with a ground wire at the other end; the second type of voltage measuring device comprises a first voltage measuring device and a second voltage measuring device.

Example two: this embodiment should be understood as a vacuum circuit breaker overvoltage combination suppression system and device, which at least includes all the features of any one of the previous embodiments and is further improved on the basis of the features of the previous embodiments, wherein the system and device are characterized by comprising a 10kV bus, a reactor group connected in parallel, a station transformer, a first type of voltage measurement device, an arrester, a second type of voltage measurement device and a circuit breaker, the reactor group is configured to be connected in parallel with the 10kV bus to form a first branch, and the station transformer is configured to be connected in parallel with the 10kV bus to form a second branch; the first type of voltage measuring device is configured to be connected with the 10kV bus in parallel to form a third branch, and a fuse is connected to the third branch in series; the lightning arrester is configured to be connected with the 10kV bus at one end and connected with a ground wire at the other end; the second class of voltage measuring devices comprises a first voltage measuring device and a second voltage measuring device, the first voltage measuring device is configured to measure on the first branch, and the second voltage measuring device is configured to measure on the second branch; the circuit breaker is connected in series on the first branch and the second branch and is used for switching on and switching off power supply lines of the first branch and the second branch. The second branch is configured to be provided with an a connection point and a b connection point; the a connection point is arranged at the near side of the output end of the circuit breaker, and the lightning arrester is installed at the a connection point; the b connection point is arranged between the first voltage measuring device and the station transformer, and the lightning arrester and the RC absorber are installed at the b connection point. The 10kV bus is also configured to be connected with a current-limiting reactor and a main transformer in parallel to form a fourth branch. Specifically, in this embodiment, the reactor group is formed by connecting a plurality of reactors in parallel, and a person skilled in the art of the reactor can calculate the required model and power according to actual needs. In the embodiment, the reactor is of a model number of BKK-2667/10, the single-phase rated capacity of the reactor is 2667Mvar, and the simulated equivalent inductance is 39.8 mH. In this embodiment, the main transformer is fully called a main transformer, the model SFSZ10-240000/220 of the main transformer has a rated capacity of 180MVA, the first branch and the second branch are connected in series by a cable, and specifically, the output end of the circuit breaker of the first branch is connected in series with the cable to connect the reactor; the output end of the circuit breaker of the second branch circuit is connected with the cable in series to connect the station transformer. The transformer for the station is fully called a transformer for the station. In this example, the cable is model ZRB-YJV 22-8.7/15-3X 240, has a capacitance per unit length of about 0.3nF/m, an inductance per unit length of about 0.35uH/m, and a unit AC resistance of about 0.156 Ω/km.

In this embodiment, the model selection of the vacuum circuit breaker is calculated by a model. In this embodiment, the simulation model of the vacuum circuit breaker is established, and the parameters of the vacuum circuit breaker are as follows: the model number is KYN28A-12, the rated voltage is 12kV, the rated current is 1250A, the rated short-circuit on-off current is 31.5kA, and the cut-off value is generally 4-6A. The RC resistance-capacitance absorber is formed by connecting a resistor R and a capacitor C in series, and is connected with a shunt reactor in parallel when the RC resistance-capacitance absorber is installed on site, and a single-phase equivalent circuit of the RC resistance-capacitance absorber is shown in the attached drawing. In the attached drawings, Us is a bus-side equivalent power supply; ls is a bus side equivalent inductance; cs is equivalent ground capacitance at the bus side; QF is a vacuum circuit breaker; lc is the equivalent inductance of the parallel resistance connecting cable; cc is the equivalent capacitance to ground of the reactor including the connecting cable; l is a shunt reactor; when the circuit breaker opens the shunt reactor, the interception overvoltage frequency and the peak value are expressed by the formulas (1) and (2), the attenuation coefficient is expressed by the formula (3), and the reignition overvoltage oscillation frequency is approximate to the formula (4).

As can be seen from the expressions (1) to (4), when the off-cutoff value I0 and the off-voltage U0 are constant, the oscillation frequency of the overvoltage and the amplitude of the restrike overvoltage frequency overvoltage can be reduced as the capacitance C increases; the resistor R can accelerate the oscillation attenuation process, so that the overvoltage is quickly reduced.

In this example, field experiments of voltage and current measurements were also performed on a 10kV capacitive overvoltage divider and an electronic current transformer (Rogowski coil). In a #1 station transformer terminal on a #2 main transformer 10kVII bus side of a 220kV transformer substation, a #2 shunt reactor loop vacuum circuit breaker load side and a power supply side, voltage and current signal measurement points are shown in FIG. 2, a measurement point 1 is a #1 station transformer head end voltage, and a measurement point 2 is a #2 reactor head end voltage, which is shown in FIG. 1. The field test is carried out for 20 times, 8 groups of cut-off data are recorded, specific numerical values are shown in table 1, Uk in the table is reactor head end voltage, Ub is station variable head end voltage, when 17-time opening operation is carried out, the reactor head end voltage is collected to 47.458kV (5.813p.u.), the station variable head end voltage is 40.79kV (5p.u.), and the maximum operation overvoltage in a non-direct grounding system below IEC specified 35kV is not allowed to exceed 4.0p.u. The following results were obtained.

Table 1:

and establishing an experimental model according to the parameters, adding actions into the experimental model, and testing the verified effect. According to the parameters and the model, ATP is preferably adopted to calculate the overvoltage of the breaker for breaking the shunt reactor, wherein A, B, C three-phase voltages are red, green and blue respectively. As can be seen from fig. 4 and 5, the maximum values of the reactor and the station variable overvoltage are close to the test values, and the validity of the experimental model in the present embodiment or whether the results of the experimental model and the field experiment are consistent is verified.

In addition, in this embodiment, the influence of the parameters and the installation position of the lightning arrester on the voltage is also analyzed. The zinc oxide arrester is used as common overvoltage suppression equipment, and overvoltage energy is released through a nonlinear resistor to achieve overvoltage suppression. In this embodiment, two types of arresters are verified, including (arrester 1) and (arrester 2). Under the condition that normal operation and power frequency voltage increase of a system are met, the volt-ampere curve of the lightning arrester (1) is higher than that of a conventional lightning arrester, and the volt-ampere curve of the lightning arrester (2) is lower than that of the conventional lightning arrester. As shown in fig. 6-8. In this embodiment, the overvoltage suppression effect of the lightning arrester with a lower voltammetry curve is better than that of the lightning arrester with a higher voltammetry curve, and for the same lightning arrester, the farther the lightning arrester is away from the lightning arrester, the overvoltage suppression capability gradually decreases. Therefore, during design, lightning arresters with lower voltage-current curves can be arranged at positions b and d in fig. 1 to suppress overvoltage, and the overvoltage amplitudes of the reactor and the station variable-head end are 12.98kV and 20.08kV respectively. In the present embodiment, a voltage profile of the overvoltage at the reactor is shown in fig. 9, and three colors of red, green, and blue are provided in fig. 9 to represent three-phase voltages, respectively. In this embodiment, it is preferable to calculate the overvoltage of the breaker opening the shunt reactor using ATP.

Different technical effects can be achieved at different installation positions of the lightning arrester, and in the embodiment, the influence of the installation position of the lightning arrester on the overvoltage of the reactor and the influence of the installation position of the lightning arrester on the voltage of the station transformer are shown in fig. 9 and 10. Wherein, fig. 9 is an image of the reactor overvoltage; fig. 10 is an image of overvoltage at the station transformer.

The first branch is configured to be provided with a c connection point and a d connection point; the c-connection point is arranged near the output end of the circuit breaker; the d-connection point is provided between the second voltage measuring device and the reactor, and the arrester is installed at the d-connection point. Specifically, in this embodiment, the arrester is formed by assembling zinc oxide resistor sheets, the resistance of the resistor sheets is in a nonlinear relationship with the voltage to be borne, and under normal operating voltage, the resistance of the resistor sheets is large and is in an insulating state, but under overvoltage, the resistor sheets are in a low-resistance state, and release overvoltage in the form of large current, so that overvoltage of the electrical equipment protected by the arrester is limited below the safety value of the equipment, and after the overvoltage disappears, the high resistance of the resistor sheets is recovered and is in an insulating state, thereby effectively protecting the insulation of the equipment from damage of the overvoltage. Specifically, it can be seen from fig. 9 and 10 that the protection mode of installing the zinc oxide lightning arrester in parallel can effectively suppress the amplitude of the system overvoltage, but the overvoltage gradient at the station transformer is as high as 12.05kV/uS, which causes the overvoltage after the lightning arrester protection to accumulate on the station transformer, and the station transformer insulation breakdown fault still may occur. Therefore, in order to further reduce the magnitude of the overvoltage on the power supply side of the reactor and the voltage gradient on the power supply side of the station transformer, in this embodiment, on the basis that the lightning arresters are installed at the b connection and the d connection in fig. 1, the RC snubber is further installed at the b connection, and the protection effect is verified. Since no national standard or power industry standard specially aiming at unified regulation of group container parameters exists at present, the value of the capacitance resistance of the resistance-capacitance absorber is not clearly regulated under different voltage levels and different application occasions, and calculation is still needed to obtain the influence of the capacitance value and the resistance value of the resistance-capacitance absorber on the electric reactor, the station overvoltage amplitude and the overvoltage gradient by adopting the capacitance range of the RC resistance container of 0.05 mu F to 0.15 mu F, the resistance value range of 100 omega to 200 omega and the installation position of b in figure 2. In this embodiment, when the capacitance value of the RC absorber is selected to be 0.1uF, the resistance value is calculated by selecting three conditions of 100 Ω, 150 Ω, and 200 Ω, and the calculation results are shown in fig. 11 and 12. Wherein, fig. 11 is an image of overvoltage at the head end of the reactor; fig. 12 is a graph of overvoltage at the head end of the station transformer. Table 2 shows the results of FIG. 9 and FIG. 10.

Table 2:

as can be seen from fig. 9, fig. 10 and table 2, on one hand, due to the influence of the branch capacitance of the reactor, the voltage gradient of the overvoltage is reduced by reducing the oscillation frequency of the overvoltage, and meanwhile, due to the fact that the resistance of the resistance-capacitance absorber consumes part of energy, the RC time constant of the high-frequency current is increased, the zero-crossing time of the current is prolonged, the reignition probability of the contact is reduced, the opening distance is increased, and the overvoltage development is suppressed, so that the overvoltage amplitude and gradient are further reduced, and therefore, compared with the lightning arrester which is only installed, after the resistance-capacitance absorber is installed, the overvoltage amplitude and voltage gradient on the power supply side of the reactor are significantly reduced. Because the capacitance value and the resistance value of the station variable branch are small, the overvoltage amplitude of the station variable power supply side is small in influence, but the overvoltage gradient of the station variable power supply side is obviously reduced due to the influence of the reactor branch resistance-capacitance absorber on the overvoltage oscillation frequency, and the overvoltage amplitude and the voltage gradient are reduced firstly and then increased along with the increase of the resistance value.

And when the resistance value is 150 omega, the resistance value is calculated by respectively selecting three working conditions of 0.05uF, 0.1uF and 0.15 uF. As can be seen from fig. 13, fig. 14, and table 5, due to the influence of the reactor branch resistor-capacitor absorber, when the capacitance value increases from 0.05 μ F to 0.1 μ F, the station variable overvoltage steepness decreases, that is, the suppression capability of the station variable overvoltage increases as the capacitance value increases;

table 3:

when the capacitance value is increased from 0.1 muF to 0.15 muF, the overvoltage amplitude and gradient of the reactor are increased, namely, the overvoltage suppression capability is reduced, therefore, the overvoltage suppression device can adopt a 0.1uF/150 omega resistance-capacitance absorber for overvoltage suppression.

The reactor group includes that a plurality of group's reactor is parallelly connected to form, the reactor includes a plurality of electric capacity, a pair of PCB board, a pair of capacitance connecting piece, the insulating head of electric capacity and electric capacity insulating cylinder, and is a pair of PCB board parallel arrangement, each the electric capacity sets up a pair of between the PCB board, each the electric capacity is with a pair of the length direction of PCB board is placed perpendicularly, and is a pair of capacitance connecting piece and a pair of the both ends of PCB board are connected, capacitance connecting piece is the I shape structure just be equipped with a plurality of connecting hole on the capacitance connecting piece, the insulating head of electric capacity passes through the fastener the connecting hole with capacitance connecting piece connects, and is a pair of the PCB board nestification in the electric capacity insulating cylinder. Specifically, the two ends of each capacitor are respectively and fixedly connected to the PCB boards 1 on the two sides, and the PCB boards 1 and the capacitors are arranged at equal intervals. In this embodiment, two ends of the pair of PCB boards 1 are fixedly connected to a pair of capacitor connectors 5, and the pair of capacitor connectors 5 are connected by screws or bolts to ensure stable connection between the devices. In this embodiment, the capacitor connecting member 5 is disposed in an i-shape, that is: the capacitor connecting piece 5 comprises two side plates 6 and a vertical plate 7, wherein the side plates 6 are arranged at two ends of the vertical plate 7, and two ends of the vertical plate 7 are fixedly connected with one side of the side plates 6. The connecting holes comprise a first connecting hole and a second connecting hole, the first connecting hole is formed in the two side plates 6, and the second connecting hole is formed in the vertical plate 7; the first connecting hole and the second connecting hole vertically penetrate through the two side plates 6 and the vertical plate 7 respectively. Specifically, the capacitor insulation end socket penetrates through the second connecting hole through a fastener to be connected with the capacitor connecting piece. The capacitor connecting rod 2 is fixedly connected with the pair of PCB boards 1, and in this embodiment, the connecting rod is fixedly connected with the pair of PCB boards 1 through a screw or a bolt. In this embodiment, the screws or bolts penetrate through the through holes of the capacitor connecting members 5 to be fixedly connected with the pair of PCB boards 1. It is a pair of capacitor connecting piece 5 keeps away from one side of PCB board 1 is equipped with electric capacity insulation head 4, electric capacity insulation head 4 with electric capacity insulating cylinder 11 cooperation is used, and is a pair of PCB board 1 and each the electric capacity is sealed to be in a set of inside the electric capacity insulating cylinder 11, guarantees the inside and the external environment mutual isolation of electric capacity insulating cylinder 11 guarantee the good electric conductivity of reactor. In addition, the capacitor insulation tube 11 and each device are sealed and poured. The casting material includes, but is not limited to, several materials listed below: resins, epoxies, and the like. In order to reduce the eddy current loss of the lead-out portion of a single capacitor in the present embodiment, the capacitor is placed in a manner perpendicular to the extending direction of the PCB board 1. The capacitor connecting piece 5 comprises a pull rod 9 and a group of semi-circular truncated cones 10, wherein the two ends of the pull rod 9 are respectively used for connecting the group of semi-circular truncated cones 10 together to form a symmetrical shape with the midpoint of the pull rod 9 as a symmetrical center. One end of the capacitance connecting rod 2 is fixedly connected with the symmetrical center of the pull rod 9, and the other end of the capacitance connecting rod extends out perpendicularly towards one side far away from the pull rod 9.

The capacitor insulating cylinder is internally sealed and poured, a plurality of umbrella skirts are nested outside the insulating cylinder, and the umbrella skirts and the insulating cylinder are coaxially arranged. In particular, it is provided that the radii of the various sheds 20 are not uniform, namely: the adjacent sheds 20 have different radiuses, and the two types of sheds 20 are arranged at equal intervals, and the sheds 20 with two radiuses are arranged at intervals. Specifically, resin or other common filling materials are respectively poured into the space between each capacitor and one group of the PCB boards 1. In this embodiment, the capacitance insulating cylinder 11 is provided with two kinds of umbrella skirts 20 with different radii on the periphery thereof, and the umbrella skirts 20 of the respective kinds are respectively provided coaxially with the capacitance insulating cylinder 11 and are provided at equal intervals along the length direction of the torch capacitance insulating cylinder 11. In this embodiment, the radii of adjacent sheds 20 are not uniform.

All be equipped with a plurality of on a curb plate of PCB board and lead to the groove to with the extending direction of PCB board is parallel, each lead to the groove along the extending direction of PCB board is equidistant to be set up. Specifically, the through grooves 21 on the PCB 1 allow the distance between the capacitors to be adjusted, so that the capacitors can be packaged as needed. In this embodiment, the through grooves 21 extend along the length direction of the PCB board 1, so that the through holes of the PCB board 1 are adjusted. In addition, in this embodiment, the pair of PCB boards 1 includes an upper board and a lower board, the through groove 21 is disposed on any one of the side boards 6, or the through groove 21 is disposed between the upper board and the lower board, and the through groove 21 of the upper board and the through groove 21 of the lower board are respectively disposed correspondingly, so that each capacitor can be adjusted on the PCB board 1, the distance between each capacitor is more uniform, and the eddy current loss between the resistors is reduced to the minimum.

Example three: the present embodiment should be understood to include at least all the features of any one of the foregoing embodiments and further improve on the same, and in particular, the present embodiment further provides a resistor, wherein the resistor includes a resistor cylinder 14, a pair of insulation cylinder sealing heads 15, a pair of resistor connecting members 13, and a resistor insulation cylinder 19, two ends of the resistor cylinder 14 are connected to the pair of resistor connecting members 13, one side of one group of the resistor connecting members 13 away from the resistor cylinder 14 is connected to the insulation cylinder sealing head 15, the resistor insulation cylinder 19 is nested in the resistor cylinder 14, and two ends of the resistor insulation cylinder 19 are connected to the insulation sealing heads. The resistance connecting pieces 13 are arranged at two ends of the resistance cylinder 14, and the resistance cylinder 14 is fixedly connected. One side of resistance connecting piece 13 keeping away from resistance cylinder 14 is equipped with insulating cylinder seals head 15, insulating cylinder seals head 15 with resistance connecting piece 13 coaxial setting. In this embodiment, the pair of insulation tube sealing heads 15 includes a resistance connecting rod 8, a connecting platform 16 and a circular truncated cone, the circular truncated cone is coaxial with the resistance connecting piece 13, and two ends of the connecting platform 16 are fixedly connected with the inner wall of the circular truncated cone. The body of the connecting table 16 is provided with a plurality of through holes, and the orientation of the through holes is parallel to the axis of the circular truncated cone. One end of the resistance connecting rod 8 is fixedly connected with the connecting table 16, and the other end of the resistance connecting rod 8 extends out perpendicularly towards the side far away from the connecting table 16. With the resistive connecting rods 8 enabling the connection of the resistor with external devices. In this embodiment, both ends of the resistor cylinder 14 are coaxially and fixedly connected to a pair of the resistor connecting members 13. The resistor connecting rod 8 arranged on the pair of insulating sealing heads enables an external device to be connected with the resistor. In an embodiment, the connecting table 16 is disposed inside the circular truncated cone, specifically, the connecting table 16 is disposed on an inner wall of the circular truncated cone and is fixedly connected with the inner wall of the circular truncated cone to form a supporting table, and the resistor connecting rod 8 is disposed on the supporting rod and is parallel to an axis of the resistor cylinder 14. The inner part of the resistance insulating cylinder 19 is poured in a sealing mode, a plurality of umbrella skirts 20 are nested outside the resistance insulating cylinder 19, and each umbrella skirt 20 and the resistance insulating cylinder 19 are coaxially arranged. The resistance insulation cylinder 19 is formed by winding constantan or nickel-chromium alloy resistance wires on a ceramic framework and pouring the constantan or nickel-chromium alloy resistance wires in a sealing manner. The sheds 20 arranged on the periphery of the resistance insulating cylinder 19 comprise two sheds 20 with different radiuses, and the adjacent sheds 20 are different in radius, that is, the sheds 20 with the two radiuses are arranged along the length direction of the resistance insulating cylinder 19 in a staggered manner. The arrangement of the shed 20 increases the creepage distance. The resistor connecting piece 13 comprises a circular ring 17 and a fixing plate 18, the circular ring 17 is close to the shaft diameter of the resistor cylinder 14 and is coaxially nested with the resistor cylinder 14, the fixing plate 18 is arranged in the circular ring 17, and two ends of the fixing plate 18 are fixedly connected with the inner wall of the circular ring 17 respectively. The fixing plate 18 is provided with a plurality of through holes, and the orientation of each through hole is parallel to the axis of the circular ring 17. Each through hole value arranged on the fixing plate 18 is connected with the insulating sealing head more efficiently and conveniently. In this embodiment, when the resistor connecting member 13 is connected to the insulating sealing head, the connection is made by bolts or screws. The fixing plate 18 is disposed on one side of the circular ring 17 and is fixedly connected with the inner wall of the circular ring 17 to form a resistance accommodating chamber 12. When the resistor cylinder 14 is connected with the accommodating cavity in a nested manner, one end of the resistor cylinder 14 is soaked in the resistor accommodating cavity 12.

In conclusion, the overvoltage combined suppression system and device for the vacuum circuit breaker can effectively suppress the overvoltage amplitude of the system by adopting a protection mode of installing the zinc oxide lightning arresters in parallel; the oscillation frequency of the overvoltage and the amplitude of the restrike overvoltage frequency overvoltage can be reduced by adopting the arrangement of the RC resistance container; the resistor R can accelerate the oscillation attenuation process, so that the overvoltage is quickly reduced; the zinc oxide lightning arrester is used as common overvoltage suppression equipment, and overvoltage energy is released through the nonlinear resistor to achieve overvoltage suppression; by adopting the matching use of the reactor and the resistor, the overvoltage of the circuit breaker in the switching process is effectively ensured, and the phenomena of easy breakdown and re-ignition are overcome.

Although the invention has been described above with reference to various embodiments, it should be understood that many changes and modifications may be made without departing from the scope of the invention. That is, the methods, systems, and devices discussed above are examples. Various configurations may omit, substitute, or add various procedures or components as appropriate. For example, in alternative configurations, the methods may be performed in an order different than that described, and/or various components may be added, omitted, and/or combined. Moreover, features described with respect to certain configurations may be combined in various other configurations, as different aspects and elements of the configurations may be combined in a similar manner. Further, elements therein may be updated as technology evolves, i.e., many elements are examples and do not limit the scope of the disclosure or claims.

Specific details are given in the description to provide a thorough understanding of the exemplary configurations including implementations. However, configurations may be practiced without these specific details, for example, well-known circuits, processes, algorithms, structures, and techniques have been shown without unnecessary detail in order to avoid obscuring the configurations. This description provides example configurations only, and does not limit the scope, applicability, or configuration of the claims. Rather, the foregoing description of the configurations will provide those skilled in the art with an enabling description for implementing the described techniques. Various changes may be made in the function and arrangement of elements without departing from the spirit or scope of the disclosure.

In conclusion, it is intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that these examples are illustrative only and are not intended to limit the scope of the invention. After reading the description of the invention, the skilled person can make various changes or modifications to the invention, and these equivalent changes and modifications also fall into the scope of the invention defined by the claims.

Claims

1. The overvoltage combined suppression system of the vacuum circuit breaker is characterized by comprising a 10kV bus, a reactor group, a station transformer, a first class voltage measuring device, a lightning arrester, a second class voltage measuring device and a circuit breaker, wherein the reactor group is connected in parallel with the 10kV bus to form a first branch;

the first type of voltage measuring device is a voltage transformer and is configured to be connected with the 10kV bus in parallel to form a third branch, and a fuse is connected to the third branch in series;

the circuit breakers are respectively connected in series on the first branch and the second branch and are used for switching on and switching off power supply circuits of the first branch and the second branch;

the reactor group includes that a plurality of group's reactor is parallelly connected to form, the reactor includes a plurality of electric capacity, a pair of PCB board, a pair of capacitance connecting piece, the insulating head of electric capacity and a capacitance insulating cylinder, and is a pair of PCB board parallel arrangement, each the electric capacity sets up a pair of between the PCB board, each the electric capacity is with a pair of the length direction of PCB board is placed perpendicularly, and is a pair of capacitance connecting piece and a pair of the both ends of PCB board are connected, capacitance connecting piece is the I shape structure just be equipped with a plurality of connecting hole on the capacitance connecting piece, the insulating head of electric capacity passes through the fastener the connecting hole with capacitance connecting piece connects, and is a pair of the PCB board nestification in the capacitance insulating cylinder.

2. The vacuum circuit breaker overvoltage combination suppression system according to claim 1, wherein said second branch is configured to provide an a connection point and a b connection point;

3. The vacuum circuit breaker overvoltage combined suppression system according to claim 1, wherein said 10kV bus is further configured to connect a current limiting reactor and a main transformer in parallel to form a fourth branch.

4. The vacuum circuit breaker overvoltage combination suppression system of claim 1, wherein said first branch is configured to provide a c connection point and a d connection point;

the c-connection point is arranged near the output end of the circuit breaker;

5. The overvoltage combination suppression system for vacuum circuit breakers according to claim 1, wherein said capacitor insulating cylinder is hermetically cast inside and a plurality of sheds are nested outside said insulating cylinder, each shed being disposed coaxially with said insulating cylinder.

6. The overvoltage combination suppression system for vacuum circuit breakers according to claim 1, wherein a plurality of through slots are formed in each of the side plates of said PCB, the slots of said through slots being oriented parallel to the direction of extension of said PCB, and each of said through slots being disposed at equal intervals along the direction of extension of said PCB.