CN117728369B - Electromagnetic voltage transformer overvoltage suppression assembly based on PTC - Google Patents

Abstract

The invention relates to a thermosensitive device which is an electromagnetic voltage transformer overvoltage suppression component based on PTC, comprising a primary harmonic eliminator connected in series between a neutral point and a grounding point at the high-voltage side of PT, and a resistor-reducing device and a fixed-value resistor connected in parallel with the primary harmonic eliminator. The resistor-reducing device and the fixed resistor are connected in series, and the resistor-reducing device is positioned on the output side of the fixed resistor. The PTC thermistor is used as the internal resistance core of the primary harmonic eliminator, and the positive temperature coefficient characteristic of the PTC thermistor is utilized, so that the PTC thermistor is in a low-resistance state in normal operation of the power grid system, and the operation of the power grid system is not influenced. And when PT overvoltage occurs in the power grid system, the PT overvoltage is restrained by entering a resistance state and rapidly increasing the resistance value.

Description

Electromagnetic voltage transformer overvoltage suppression assembly based on PTC

Technical Field

The invention relates to a thermosensitive device, in particular to a suppression component for controlling electromagnetic PT ferromagnetic resonance overvoltage based on PTC materials.

Background

In a power grid, faults of 10kV and 35kV dry electromagnetic voltage transformers frequently occur, a PT high-voltage side fuse is fused if the faults are light, PT insulation flashover is possibly caused to explode if the faults are heavy, and even a bus three-phase short circuit accident is caused. Among them, the reason for the fuse blowing of the PT high voltage side fuse and even the bus short circuit fault is mainly due to PT overvoltage.

In the neutral point ungrounded system and the low current grounded system, the three phases are basically balanced under the normal running condition of PT, and the power neutral point voltage is basically not displaced. However, when a disturbance occurs in the system (such as a closing neutral bus, disappearance of a single-phase arc light ground fault, severe change of a system load, and the like), the potential of a neutral point of the power supply deviates from the ground potential, so that unbalanced rise of single-phase, two-phase or three-phase voltages occurs, and thus iron saturation of a nonlinear characteristic iron core of the PT may be caused, and further continuous and high-amplitude resonance overvoltage of the PT occurs, namely ferromagnetic resonance overvoltage occurs.

At present, the harmonic elimination measures adopted for PT overvoltage in the above-mentioned process are mainly divided into two types of "changing system parameters" and "increasing system damping". Among these, one of the measures to "increase the system damping" is that the PT high-side neutral point is grounded through a resistor.

The reference of the measure of grounding the PT high-voltage side neutral point through the resistor is PT high-voltage side neutral point resistorWhen the current is large enough, the excitation current of the PT primary winding can be limited, and further the PT iron core is prevented from being saturated, so that resonance is effectively prevented or eliminated. And, if the resistance/>And when the trend is ++, the inductor does not participate in the zero sequence loop, and the condition of resonance overvoltage caused by saturation of the PT iron core does not exist. However, when this measure is taken, a resistance with a large resistance value is selected/>The following conflicts exist in the application:

1. If the resistance is When single-phase grounding occurs in a power grid system, most of zero-sequence voltage drops to the resistorThe voltage of the triangle winding with the voltage-variable opening is too low, so that the action of the protection device is affected;

2. considering PT neutral point long-term operation voltage limit value, sensitivity of grounding indication and accuracy of insulation monitoring, resistance An excessively large resistance value is not preferable.

Disclosure of Invention

In order to solve the problems that when the PT high-voltage side neutral point is adopted to inhibit PT ferromagnetic resonance overvoltage through a resistor grounding measure, the action of a protection device is affected and the sensitivity of grounding indication and the accuracy of insulation monitoring are reduced by selecting a resistor with a large resistance value for application, the invention provides the following technical scheme:

A PTC-based electromagnetic voltage transformer overvoltage suppression assembly comprising: the primary harmonic eliminator is connected in series between the PT high-voltage side neutral point and the grounding point, and the resistor-reducing device and the fixed-value resistor are connected in parallel with the primary harmonic eliminator. The resistor-reducing device and the fixed value resistor are connected in series, and the resistor-reducing device is positioned on the output side of the fixed value resistor.

The primary harmonic eliminator is a flow-sensitive harmonic eliminator with positive temperature coefficient characteristics. The inner resistor core is made of PTC material, and the outer shell is provided with a mounting position for mounting the resistor-reducing device.

The resistor-reducing device comprises: plunger, control assembly and loose pin.

The plunger is arranged in the installation position of the outer shell of the primary harmonic eliminator. The inner end surface of the primary harmonic eliminator contacts with the inner choke core to conduct heat, and the outer end of the primary harmonic eliminator is provided with a through hole type heat conducting channel.

The control assembly is arranged outside the installation position of the primary harmonic eliminator outer shell. It contains a PCB board and a coil. The PCB is connected with the primary harmonic eliminator in parallel and connected with the constant value resistor in series; the coil is controlled by the PCB circuit.

The movable pin is arranged at the installation position of the outer shell of the primary harmonic eliminator and is controlled by the magnetic field of the coil contained in the control assembly to pass through the annular cavity and the heat conduction channel of the coil. The tail part of the radiator is displaceable into contact with the plunger by passing through the heat conducting channel, so that heat of the plunger is transferred to the tail part of the radiator in a heat conduction mode, and the head part of the radiator radiates the heat into the surrounding air in a heat radiation mode so as to accelerate the temperature reduction of the inner choke core of the primary harmonic eliminator.

Further, the primary detuner comprises: sleeve, top cap, PTC thermistor and base.

The sleeve is used as an outer shell of the primary harmonic eliminator, a lead wire for connecting a PT high-voltage side neutral point is arranged at the top end of the sleeve, a through hole type side opening is formed in the side wall of the sleeve, and the side opening is used as part of an installation position of the outer shell of the primary harmonic eliminator.

The top cover is filled in the cylinder cavity at the top of the sleeve and is connected with a wire arranged at the top end of the sleeve.

The PTC thermistor is used as an internal choke of the primary harmonic eliminator and is filled in the sleeve barrel cavity. The top of the device is provided with a wire connected with the top cover, and the bottom of the device is provided with a wire for grounding.

The base is sleeved on the barrel at the bottom of the sleeve. The bottom wall of the inner cavity is connected with a lead arranged at the bottom of the PTC thermistor.

Further, the sleeve is divided into an outer cylinder and an inner cylinder. The outer cylinder is coated on the outer side wall surface of the inner cylinder, and the top of the outer cylinder is covered right above the inner cylinder. The wire at the top end of the sleeve passes through the top end of the outer cylinder, the outer end of the wire is connected with the neutral point of the PT high-voltage side, and the inner end of the wire is connected with the top cover.

Further, the top surface of the top cover is provided with a first hole for connecting the inner end of the wire arranged at the top end of the sleeve, and the bottom surface of the top cover is provided with a second hole for connecting the wire arranged at the top of the PTC thermistor. Wherein, the first hole and the second hole are blind hole type threaded holes and are provided with bolts for fastening wires connected with the holes.

Further, the base includes: the device comprises a groove drum, side pipes and a bracket.

The groove cylinder is sleeved on the cylinder body at the bottom of the sleeve. The side wall of the PTC thermistor is provided with a through hole which is aligned with and communicated with the side hole, and the bottom surface of the barrel cavity of the PTC thermistor is provided with a hole III for connecting a wire arranged at the bottom of the PTC thermistor. Wherein, the third hole is a blind hole type threaded hole and is provided with a bolt for fastening a wire connected with the hole.

The side pipe is arranged outside the side wall of the groove drum. The pipe orifice at the inner end is aligned with and communicated with the through hole arranged on the side wall of the groove drum, a socket for inserting the loose pin is arranged on one side wall of the pipe body, and a through hole opposite to the socket is arranged on the other side wall of the pipe body.

The bypass pipe is arranged outside the side wall of the side pipe. The pipe orifice is aligned with and communicated with the through opening arranged on the side wall of the side pipe.

One end of the bracket is fixed outside the side wall of the base, and the other end of the bracket is provided with a hole site for installing a control component.

The through hole, the side pipe, the bracket and the side hole which are arranged on the side wall of the groove drum jointly form the whole of the installation position of the outer shell of the primary harmonic elimination device.

Further, the groove drum is a drum body with a single drum opening. The side pipe is a double-pipe-opening pipe body. The bypass pipe is a pipe body with a single pipe orifice. The hole cavity of the hole site arranged at the end part of the bracket is X-shaped, and the hole is a through hole.

Further, the plunger includes: a heat conduction block and a block sleeve.

The heat conducting block is filled in a channel formed by the side pipe, the through hole formed in the side wall of the groove drum and the side hole, and the inner end surface of the heat conducting block is abutted against the outer side wall surface of the PTC thermistor.

The block cover is coated on the other surfaces except the inner end surface of the heat conducting block.

The heat transfer channel is in the form of a through hole that extends through the heat transfer block and block sleeve and that is alignable and communicable with the socket.

Further, the control assembly includes: control box and coil box.

The PCB board contained in the control assembly is arranged in the control box. The bottom cover part for sealing the pipe orifice at the outer end of the side pipe extends from the bottom of the box.

The coil contained in the control assembly is arranged in the coil box. The box body is provided with a through hole for the running pin to pass through, the through hole and the annular cavity of the coil form a channel for controlling the running pin to pass through together, and the channel is aligned with the socket. The box body is also provided with a protruding part which is matched with the hole phase arranged at the end part of the bracket.

Further, the loose pin includes: a pin housing and a pin core.

The pin housing serves as a thermal insulation. The head part of the shell is of a hollow thin shell structure, and hollow openings are uniformly formed in the shell wall. The outer wall of the head shell is connected with a straight tubular outer rod capable of passing through the annular cavity of the coil contained in the control assembly, and the tail of the outer rod can pass through the heat conducting channel. In addition, the tail of the outer rod is adjacent to an exposed area.

The pin core plays a role in heat dissipation. The head part is of a hollow thin shell structure, and the outer surface of the shell wall is attached to the inner surface of the shell wall of the head part of the pin shell. The outer part of the head shell wall is connected with an inner rod which can be plugged in the outer rod tube cavity. The upper rod body of the inner rod is provided with an embedded groove, and an iron core controlled by a coil magnetic field contained in the control assembly is embedded in the groove. The tail of the inner rod is provided with an insert exposed at the exposed area.

Further, the pin housing head housing wall is composed of two housing bodies with the two housing openings being matched, and the two housing bodies are an outer top housing and an outer bottom housing respectively. The head end of the outer rod is connected with the outer cover body, and the inner cavities of the outer rod and the outer cover body are communicated.

Further, the shell wall of the head part of the pin core is formed by two cover bodies with the cover openings being matched, and the two cover bodies are an inner top cover and an inner bottom cover respectively. The head of the inner rod is connected with the cover body of the inner bottom cover. The core can be plugged into the outer rod inner cavity. The inner wall surface of the embedded piece is attached to the side wall surface of the tail part of the inner rod, and the outer wall surface of the embedded piece can be contacted with the inner cavity wall surface of the heat conducting channel.

Further, the outer rod is a single-port pipe body. The pipe orifice is connected with the outer bottom cover, and the inner cavities of the pipe orifice and the outer bottom cover are communicated; the side wall of the tail part is provided with a through hole which is used as an exposed area adjacent to the through hole, and the side wall of the tail part is also provided with a convex rib opposite to the through hole.

In addition, the socket, the heat conduction channel and the bypass pipe are provided with sliding grooves matched with the convex ribs on the inner cavity wall surfaces of the socket, the heat conduction channel and the bypass pipe.

In addition, the inserted sheet is matched with a through hole arranged on the side wall of the tail part of the outer rod.

Further, or the outer rod is a double-port pipe body. The orifice of the head end of the device is connected with the outer cover, and the inner cavities of the two are communicated; the pipe orifice at the tail end is externally connected with a section of virtual area serving as an exposed area adjacent to the virtual area, and the tail end of the virtual area is provided with a gasket which is the same as the outer rod in material. Wherein, this gasket is laminated with the terminal surface of interior pole afterbody.

In addition, the inserts are in the shape of a round straight tube. The outer rod is sleeved at the tail part of the inner rod and is matched with a virtual area circumscribed by the outer rod.

Compared with the prior art, the invention has the beneficial effects that:

1. The PTC thermistor is used as the internal resistance core of the primary harmonic eliminator, and the positive temperature coefficient characteristic of the PTC thermistor is utilized, so that the PTC thermistor is in a low-resistance state in normal operation of the power grid system, and the operation of the power grid system is not influenced. That is, in the measure of suppressing the PT overvoltage by the PT high-voltage side neutral point through the resistor grounding, the problems that the action of the protection device is affected and the sensitivity of the grounding instruction and the accuracy of the insulation monitoring are reduced due to the large resistance value of the primary harmonic eliminator are avoided.

2. The PTC thermistor is used as an internal resistance core of the primary harmonic eliminator, and by utilizing the positive temperature coefficient characteristic of the PTC thermistor, the PTC thermistor enters a resistance state when PT overvoltage occurs in a power grid system, and the PT overvoltage is restrained by rapidly increasing the resistance value of the PTC thermistor. The dynamic change of the resistance of the PT is regulated according to the PT overvoltage, so that the PT overvoltage can be restrained, and the influence on the operation of a power grid system can be reduced.

3. By additionally arranging the resistor-reducing device for the transformation of the primary harmonic eliminator, after the primary harmonic eliminator inhibits PT overvoltage, the resistor-reducing device can be utilized to accelerate the heat dissipation of the PTC thermistor, so that the temperature of the PTC thermistor can be quickly reduced toSo that the PTC thermistor can quickly enter a low-resistance state by utilizing the positive temperature coefficient characteristic of the PTC thermistor.

4. The design of the detachable resistor-reducing device main body is adopted in the resistor-reducing device for radiating the movable pin to the outside, so that the movable pin is convenient to clean and maintain. That is, when the movable pin needs to be cleaned, the movable pin can be pulled out from the coil box for cleaning.

5. The plunger in the resistor reducer for conducting heat of the PTC thermistor is blocked inside the installation position of the outer shell of the primary harmonic eliminator, so that the plunger can only radiate heat outwards through the movable pin. When the resistor-reducing device is in a non-working state, the plunger cannot radiate heat to the outside through the movable pin, so that the temperature-reducing operation of the PTC thermistor is more controllable.

Drawings

FIG. 1 is a schematic diagram of the wiring of the present invention;

FIG. 2 is a schematic view of the external structure of the present invention;

FIG. 3 is a schematic perspective view of a primary detuner, partially cut away, in accordance with the present invention;

FIG. 4 is a schematic diagram of a three-dimensional structure of a resistor-reducing device according to the present invention;

FIG. 5 is a schematic view of a sleeve in a perspective cut-away configuration according to the present invention;

FIG. 6 is an exploded view of the top cover of the present invention in perspective cut-away configuration;

FIG. 7 is a schematic diagram showing a perspective structure of a PTC thermistor according to the present invention;

FIG. 8 is a schematic diagram showing a perspective structure of a PTC thermistor according to the present invention;

FIG. 9 is an exploded cross-sectional view of a three-dimensional cut-away structure of a base of the present invention;

FIG. 10 is a schematic view of a plunger of the present invention in perspective cut-away;

FIG. 11 is a schematic view of a perspective cut-away structure of a base and plunger combination of the present invention;

FIG. 12 is an exploded view of a control assembly of the present invention in perspective cut-away;

FIG. 13 is a schematic perspective view of a control assembly according to the present invention;

FIG. 14 is a schematic view of a three-dimensional cutaway of a loose pin of the present invention;

FIG. 15 is an exploded view of the three-dimensional structure of the pin housing of the present invention;

FIG. 16 is a perspective exploded view of a pin housing according to the present invention;

FIG. 17 is an exploded view of the perspective structure of the pin core of the present invention;

FIG. 18 is a state diagram of the resistor-down resistor of the present invention when not in operation;

Fig. 19 is a state diagram of the resistor-reducing device in the present invention when it is operated.

In the drawings, the list of part names represented by the reference numerals is as follows:

1-primary harmonic eliminator;

100-sleeve, 110-outer cylinder, 120-inner cylinder and 101-side port;

200-a top cover, 201-a first hole and 202-a second hole;

300-PTC thermistor;

400-base, 410-grooved drum, 420-side pipe, 430-side pipe, 440-bracket, 401-hole three, 402-socket;

2-a resistor-reducing device;

500-plunger, 510-heat conducting block, 520-block sleeve and 501-heat conducting channel;

600-control assembly, 610-control box, 620-coil box;

700-loose pin, 710-pin shell, 711-outer cap, 712-outer cap, 713-outer bar, 714-bead, 720-pin core, 721-inner cap, 722-inner cap, 723-inner bar, 724-core, 725-slug, 701-exposed area;

3-fixed value resistor.

Detailed Description

Preferred embodiments for carrying out the present invention are described in detail below, and a clear and complete description thereof is provided with reference to the accompanying drawings.

The invention is suitable for a 10kV neutral point ungrounded system and a small current grounded system in a power grid, and provides an electromagnetic voltage transformer overvoltage suppression component based on PTC aiming at adopting a measure of suppressing PT ferromagnetic resonance overvoltage in the system by grounding a resistor at a PT high-voltage side neutral point.

Referring to fig. 1, the overvoltage suppression component of the PTC-based electromagnetic voltage transformer provided by the present invention includes three parts, which are respectively: primary harmonic eliminator 1, resistor-reducing device 2 and fixed value resistor 3.

The input end of the primary harmonic eliminator 1 is connected with a PT high-voltage side neutral point through a wire, and the output end of the primary harmonic eliminator 1 is grounded through being connected with a grounding point. That is, the PT high-side neutral point is grounded through the primary detuner 1. The primary harmonic eliminator 1 is a flow-sensitive harmonic eliminator and is used for inhibiting PT overvoltage.

The resistor-reducing device 2 and the fixed resistor 3 are connected in series to form a series circuit, and the resistor-reducing device 2 is positioned on the output side of the fixed resistor 3. The series circuit formed by the two is connected in parallel with the primary harmonic canceller 1. When the series circuit formed by the resistor-reducing device 2 and the fixed value resistor 3 is loaded, the resistor-reducing device 2 can act through information processing, and the primary harmonic eliminator 1 is helped to accelerate cooling. The resistor-reducing device 2 is also provided with an input port for connecting an external power supply, and the port is connected with the external power supply through a power line, so that the external power supply supplies power to the resistor-reducing device 2, and the normal operation of the resistor-reducing device 2 is ensured.

In the present invention, the relationship among the highest resistance value of the primary detuner 1, the resistance value of the detuner 2, and the resistance value of the fixed value resistor 3 is as follows:

In the method, in the process of the invention, Is the highest resistance value of the primary harmonic eliminator 1,/>To reduce the resistance of the resistor 2/(Is the resistance of the fixed resistor 3. For example, to/>And/>For example, when the ratio of the primary harmonic eliminator 1 is equal to 0.95, the resistance value is reduced from the high resistance state toWhen the current is 0.95 times of the current outputted from the neutral point of the PT high voltage side, the current flows through the fixed resistor 3 to the resistor 2, and the resistor 2 is activated to perform corresponding action.

Referring to fig. 2-4, the primary detuner 1 and the impedance reducer 2 can be combined together. The resistor-reducing device 2 can directly act on the internal blocking core of the primary harmonic eliminator 1 during the action, so as to accelerate the cooling of the internal blocking core of the primary harmonic eliminator 1, and further enable the primary harmonic eliminator 1 to enter a low-resistance state relatively quickly.

The primary harmonic eliminator 1 includes:

sleeve 100, which serves as the outer housing of primary detuner 1. The top end of the wire is provided with a wire for connecting the neutral point of the PT high-voltage side, and the side wall of the wire is provided with a side opening 101 in a through hole shape.

A top cap 200 is filled in the top chamber of the sleeve 100. The upper part is connected with a lead arranged at the top end of the sleeve 100, and the lower part is connected with the internal choke core of the harmonic eliminator 1.

PTC thermistor 300 as the internal choke of primary resonator 1. Which is filled in the cylinder cavity of the sleeve 100, is connected with the top cover 200 and is connected with the base 400.

A base 400 sleeved on the bottom cylinder of the sleeve 100. The PTC thermistor 300 is connected to the upper part of the transformer, and the grounding point of the primary harmonic eliminator 1 is arranged below the transformer.

The primary harmonic eliminator 1 further includes:

and a mounting position for mounting the resistor 2. The side opening 101 is a part of the installation site, and the other part of the installation site is disposed on the side wall of the base 400. That is, the inside of the installation site can communicate with the cylinder chamber of the sleeve 100 through the side port 101.

The resistor-reducing device 2 includes:

A plunger 500 as a heat-conducting medium. The inner end surface of the primary harmonic eliminator 1 is completely abutted against the outer side wall surface of the PTC thermistor 300, so that heat of the PTC thermistor 300 can be transferred to the plunger 500 in a heat conduction mode. Wherein, the outer end of the plunger 500 is far away from the PTC thermistor 300, and the outer end is provided with a heat conduction channel 501 in the shape of a through hole.

A control assembly 600 that acts as a control hub. Which is mounted outside the mounting position provided for the outer housing of the primary harmonic trap 1. The circuit comprises a PCB board for monitoring the current value of the fixed value resistor 3 and carrying out information acquisition and analysis processing on the current value, and a coil which is controlled by the circuit of the PCB board to carry out on-off circuit. Wherein, the PCB board is connected in series with the fixed value resistor 3, and the PCB board is positioned at the output side of the fixed value resistor 3, and a series circuit formed by the fixed value resistor 3 and the PCB board is connected in parallel with the primary harmonic eliminator 1.

A movable pin 700 as a heat sink. Which is mounted at the mounting location of the outer housing of the primary detuner 1 and is controlled by the magnetic field of the coil contained in the control assembly 600 to travel within the annular cavity of the coil and the interior cavity of the thermally conductive tunnel 501. The head of the loose pin 700 is of a hollow thin shell structure, and hollow openings for ventilation are uniformly formed in the shell wall of the head of the loose pin. The tail of the movable pin 700 is provided with an exposure area 701, the part of the movable pin 700 in the area can be in direct contact with the wall surface of the inner cavity of the heat conduction channel 501, so that the heat of the plunger 500 can be transferred to the movable pin 700, and finally, the thin shell structure at the head of the movable pin 700 radiates the heat into the outside air in a heat radiation manner, so that the temperature of the PTC thermistor 300 is reduced, and the process of the PTC thermistor 300 entering a low-resistance state is accelerated. In addition, the hollow opening provided in the head shell wall of the loose pin 700 is used for ventilation, so that the hot air in the loose pin can escape outwards.

In the present invention, the PTC thermistor 300 has a positive temperature coefficient characteristic. That is, the PTC thermistor 300 is in a low resistance state at normal temperature, and its resistivity gradually increases as the temperature increases, and when the temperature increases to a certain threshold value, its resistivity rapidly increases with a very small increase in temperature until it enters a high resistance state as the temperature increases. Conversely, the high-resistance PTC thermistor 300 gradually decreases its resistivity as the temperature decreases, and after the temperature decreases to a certain threshold, its resistivity rapidly decreases with a very small decrease in temperature until it enters the low-resistance state as the temperature decreases. Wherein the temperature threshold limit point capable of causing the resistivity of the PTC thermistor 300 to rapidly rise is designated asThis temperature threshold limit point that causes a rapid decrease in the resistivity of the PTC thermistor 300 is denoted as/>，/>。

Therefore, when the power grid system in which the PT is located is in normal operation, the PTC thermistor 300 is in a normal temperature environment and is in a low resistance state. At this time, the resistance of the PTC thermistor 300 is far smaller than the resistance of the constant value resistor 3, and the current flowing from the neutral point on the PT high voltage side flows only to the constant value resistor 3 in a very small amount, which is almost negligible. Meanwhile, the PTC thermistor 300 in the low-resistance state does not influence the operation of the power grid system where the PT is located, and the problems that the action of the protection device is influenced and the sensitivity of the grounding indication and the accuracy of insulation monitoring are reduced due to the fact that the primary harmonic eliminator has a larger resistance value in the measure of inhibiting PT overvoltage through the grounding of the resistor at the neutral point of the PT high-voltage side are avoided.

In addition, when PT is over-voltage in the grid system, the current flowing from the PT high-voltage side neutral point increases, raising the temperature of the PTC thermistor 300. As the temperature of the PTC thermistor 300 exceedsThe resistance will rise rapidly, the difference between the resistance and the resistance of the fixed resistor 3 becomes small, at this time, the current flowing through the fixed resistor 3 is abnormal in the state when the grid system is operating normally, and the abnormal current information is monitored, collected and analyzed by the PCB board in the control module 600.

In the process of suppressing the PT overvoltage, when the PT overvoltage is suppressed from the peak, the current flowing through the constant value resistor 3 is gradually reduced. At this time, the state is obtained by the PCB board contained in the control assembly 600, the control circuit of the PCB board controls the coil to be electrified to establish a magnetic field, the movable pin 700 is driven to displace by the magnetic field and the exposed area 701 is moved to the inner cavity of the heat conduction channel 501, the movable pin 700 at the exposed area 701 is directly contacted with the wall surface of the inner cavity of the heat conduction channel 501 to realize the temperature reduction of the PTC thermistor 300, so that the temperature of the PTC thermistor 300 is quickly reduced to the temperatureSo that the PTC thermistor 300 quickly goes from a high resistance state to a low resistance state using its positive temperature coefficient characteristics.

In this way, the positive temperature coefficient characteristic of the PTC thermistor 300 is utilized, so that the PTC thermistor is not only in a low resistance state to reduce the influence on the power grid system during normal operation, but also can increase the resistance value of the PTC thermistor to inhibit PT overvoltage when the PT overvoltage occurs in the power grid system. That is, the problem that the operation of the protection device is affected and the sensitivity of the grounding instruction and the accuracy of insulation monitoring are reduced by selecting a resistor with a large resistance value for application in the measure of suppressing the PT overvoltage by grounding the resistor at the neutral point of the PT high voltage side is avoided. The invention also enables the temperature of the PTC thermistor 300 to be quickly reduced to the temperature after PT overvoltage is restrained by the resistor-reducing device 2Further, the positive temperature coefficient characteristic of the PTC thermistor 300 is better utilized, and the time for the PTC thermistor 300 to enter a low-resistance state is reduced.

Example 1

Referring to fig. 5, a further embodiment of the sleeve 100 is shown.

The sleeve 100 is divided into an outer cylinder 110 and an inner cylinder 120. Wherein the outer cylinder 110 is coated on the outer side wall of the inner cylinder 120, and the top of the outer cylinder 110 is covered right above the inner cylinder 120, and the bottom walls of the outer cylinder and the inner cylinder are in the same plane.

The wire provided at the top end of the sleeve 100 passes through the top end of the outer tube 110, and has an outer end outside the outer tube 110 to connect with the PT high voltage side neutral point, and an inner end inside the outer tube 110 to connect with the top cap 200.

The side opening 101 provided on the side wall of the sleeve 100 penetrates through the side wall of the outer cylinder 110 and the side wall of the inner cylinder 120 where the side opening is provided.

Preferably, the outer cylinder 110 is a single-port straight cylinder with a downward cylinder port, and the inner cylinder 120 is a double-port straight cylinder. The two materials are selected from insulating, waterproof, fireproof, pressure-resistant and wear-resistant materials.

In the present invention, the wire provided at the tip of the sleeve 100 is uniformly adhered and fixed to the tip of the outer cylinder 110 by an adhesive to form a seal. In addition, the outer end of the wire provided at the tip of the sleeve 100 may be fastened at the PT high-voltage side neutral point by a bolt.

Referring to fig. 6, a further embodiment of the top cover 200 is shown.

The top surface of the top cover 200 is provided with a first hole 201, and the bottom surface thereof is provided with a second hole 202. Wherein, the first hole 201 and the second hole 202 are blind hole type threaded holes and are provided with bolts for fastening the wires connected with the holes.

Preferably, the top cover 200 is made of conductive material.

In the present invention, the surface of the top cap 200 is uniformly adhered and fixed to the wall surface of the top cylinder of the sleeve 100 by using an adhesive, so that the cap body is matched with the adhesive to seal the cylinder, and the top cap 200 is covered on the top end of the PTC thermistor 300. In addition, the inner end of the wire provided at the top end of the sleeve 100 may be fastened at the hole one 201 by a bolt; the wires provided at the top of the PTC thermistor 300 may be fastened at the hole two 202 using bolts.

Referring to fig. 7 and 8, a further embodiment of the PTC thermistor 300 is shown in this embodiment.

The PTC thermistor 300 has leads at the top and bottom. When PT in the power grid system is over-voltage, PT high-voltage side neutral point current flows to the resistor of the PTC thermistor 300 through a wire arranged at the top end of the sleeve 100, a wire arranged at the top of the top cover 200 and the top of the PTC thermistor 300, then flows to the base 400 through a wire arranged at the bottom of the PTC thermistor 300, and is led to a grounding point through the base 400.

In the invention, the outer side wall surface of the PTC thermistor 300 and the barrel cavity wall surface of the inner barrel 120 are uniformly adhered and fixed by adopting an adhesive.

Referring to fig. 9, a further embodiment of the base 400 is shown.

Base 400 includes a pod 410, side tubes 420, side tubes 430, and a mount 440.

The grooved drum 410 is sleeved on the bottom drum body of the sleeve 100. The side wall is provided with a through hole which is aligned with and communicated with the side hole 101, and the bottom surface of the cylinder cavity is provided with a third hole 401. Of these, the third hole 401 is a blind hole type screw hole and is provided with a bolt for fastening a wire connected thereto. In addition, a pair of ear pieces are provided on the outer side wall surface of the bottom end of the tub 410, and a through hole for aligning with the ground point hole site is provided in the middle of the ear pieces.

Preferably, the slot cylinder 410 is a single-port straight cylinder with the cylinder port facing upwards. The cylinder cavity of the outer cylinder 110 is matched with the bottom cylinder of the outer cylinder 110 so that the outer cylinder 110 is sleeved on the bottom cylinder of the outer cylinder 110 from below.

In the invention, the wall surface of the cavity of the groove cylinder 410 and the outer side wall surface of the outer cylinder 110 are uniformly adhered and fixed by adopting an adhesive, so that the bottom of the sleeve 100 is sealed by matching with the adhesive. In addition, a wire provided at the bottom of the PTC thermistor 300 may be fastened at the hole three 401 using a bolt; the lug provided on the outer side wall surface of the bottom end of the tub 410 may be fastened to the ground point by a bolt, that is, a hole site for installing the primary resonance eliminator 1 is provided at the ground point, after the through hole of the lug provided on the outer side wall surface of the bottom end of the tub 410 is aligned with the ground point hole site, the two holes may be connected by a bolt, and the lug may be fastened to the ground point by tightening the bolt. Wherein the bolt for fastening the tub 410 at the ground point may be provided with a nut according to the need.

The side pipe 420 is connected to the outer side wall surface of the tub 410. The inner end pipe orifice is aligned with and communicated with the through opening arranged on the side wall of the groove drum 410; a socket 402 for inserting the loose pin 700 is formed on one side wall of the pipe body, and a through hole opposite to the socket 402 is formed on the other side wall of the pipe body; ear blocks with screw holes are uniformly arranged on the side wall surface of the periphery of the edge opening of the pipe orifice at the outer end of the pipe orifice.

Preferably, the side tube 420 is a double-ended straight tube. Its inner end spout is seamlessly connected to the sidewall of the bowl 410 and its lumen is in communication with the bowl 410 lumen. In addition, the inner wall surface of the outer nozzle is provided with a reference line for judging whether the plunger 500 is mounted in place.

In the present invention, the cross-sectional profiles of the inner end pipe orifice of the side pipe 420, the through opening provided in the side wall of the tank 410, and the side opening 101 are the same, so that the plunger 500 is filled into the pipe cavity of the side pipe 420 from the outer end pipe orifice of the side pipe 420, and the inner end surface of the plunger 500 can directly contact with the outer side wall surface of the PTC thermistor 300 through the side opening 101. When the inner end surface of the plunger 500 is completely attached to the outer side wall surface of the PTC thermistor 300, the outer end surface of the plunger 500 is flush with the reference line provided at the outer end nozzle of the side pipe 420. In addition, the bottom of the control assembly 600 can be fastened at the pipe orifice of the outer end of the side pipe 420 by utilizing the screw to be in threaded connection with the screw hole of the ear block arranged at the pipe orifice of the outer end of the side pipe 420, and the plunger 500 can be plugged in the pipe cavity of the side pipe 420 by utilizing the bottom of the control assembly 600.

The bypass pipe 430 is connected to an outer sidewall surface of the side pipe 420. The pipe orifice is aligned with and communicated with the through hole formed in the side wall of the side pipe 420, and the side wall of the bottom of the pipe cavity is provided with an air hole in a through hole shape.

Preferably, the bypass tube 430 is a straight tube of a single orifice. The orifice of which is seamlessly connected with the wall of the side tube 420 and the lumen of which is in communication with the lumen of the side tube 420. In addition, the air hole arranged on the side wall of the bottom of the tube cavity is adjacent to the bottom surface of the tube cavity.

In the present invention, the cross-sectional profiles of the orifice of the side pipe 430, the opening provided on the side wall of the side pipe 420 and the socket 402 are the same, and the three cooperate with the lumen area of the side pipe 420 between the socket 402 and the opening provided on the side wall of the side pipe 420 to form a straight passage adapted to the running of the movable pin 700, so that the movable pin 700 can displace along the inner cavity of the straight passage. The movable pin 700 is inserted into the base 400, and the bottom of the movable pin 700 is sequentially inserted in the order of 'socket 402-side pipe 420 cavity area between the socket 420 and the through hole provided on the side wall of the side pipe 420-side pipe 430'. In addition, the air holes arranged on the side wall of the bottom of the tube cavity of the bypass tube 430 can be used for air to enter and exit, and the lubricating oil residues on the bottom surface of the tube cavity of the bypass tube 430 can be drawn out by utilizing thin iron wires.

The bracket 440 is fixed to an outer sidewall surface of the base 400. The end of which is provided with a hole site for mounting the control assembly 600.

Preferably, the bracket 440 is composed of two bar-shaped brackets symmetrically arranged. The bracket 440 is made of insulating, waterproof, fireproof, pressure-resistant and wear-resistant materials. The two strip-shaped frames are respectively arranged at two sides of the side pipe 420, one end of each strip-shaped frame is fixedly arranged on the side wall of the side pipe 420, and the other end of each strip-shaped frame is provided with a through hole type hole with an X-shaped hole cavity for installing the control component 600.

In the present invention, the hole at the end of the bracket 440 has triangular plates on both sides of the hole cavity and the adjacent plate-shaped frame at the bottom, so that the force carried by the hole cavity is dispersed by the bevel sides of the triangular plates.

The bowl 410, side tube 420 and side tube 430 are of unitary design. The through hole, the side pipe 420, the side pipe 430, the bracket 440 and the side hole 101 arranged on the side wall of the tank 410 together form the whole of the installation position arranged on the outer shell of the primary resonance eliminator 1.

Preferably, the tub 410, the side pipe 420 and the side pipe 430 are all made of conductive metal materials, and both inner and outer surfaces of the side pipe 420 and the side pipe 430 are uniformly plated with an insulating layer to perform an insulating protection function, so that the base 400 can be grounded only through the tub 410.

Referring to fig. 10 and 11, a further version of the plunger 500 is shown in this embodiment.

Plunger 500 includes a thermally conductive block 510, a block sleeve 520, and a thermally conductive channel 501.

The heat conducting block 510 is filled in the channel formed by the side pipe 420, the through hole formed in the side wall of the groove cylinder 410 and the side hole 101, and the inner end surface of the heat conducting block is completely attached to the outer side wall surface of the PTC thermistor 300.

Preferably, the heat conducting block 510 is a solid block, which is made of a heat conducting and insulating material. The inner end surface is a cambered surface.

In the present invention, since the inner end surface of the heat conduction block 510 is a cambered surface, and can be completely adhered to the outer surface of the PTC thermistor 300. Therefore, only when the inner end surface of the heat conduction block 510 is completely adhered to the outer surface of the PTC thermistor 300, the plunger 500 can be properly filled in the passage formed by the side pipe 420, the through-hole provided in the side wall of the tub 410, and the side port 101 together, and cannot be rotated in the passage. That is, the inner end surface of the heat conduction block 510 not only allows heat of the PTC thermistor 300 to be transferred to the heat conduction block 510 by heat conduction, but also restricts rotation of the plunger 500 that is properly mounted.

The block sleeve 520 is coated on the other surfaces of the heat conducting block 510 except the inner end surface of the heat conducting block 510, and the outer surface of the block sleeve completely fits the wall surface of the channel inner cavity formed by the side pipe 420, the through hole formed by the side wall of the groove drum 410 and the side hole 101.

Preferably, the block sleeve 520 is a single-ended sleeve, and its sleeve mouth is adapted to the inner end face of the heat conducting block 510. It is made of insulating, heat-insulating and high-temp. resistant material.

In the present invention, the sleeve end surface of the block sleeve 520 and the end surface of the heat conducting block 510 are located in the same cambered surface. The block sleeve 520 and the heat conducting block 510 are uniformly adhered and fixed by adopting an adhesive. The block sleeve 520 provides insulation protection to the heat conducting block 510 and blocks heat transfer to the side tube 420 and the control box 610.

The thermally conductive channel 501 is used to transfer heat to the region of the loose pin 700 at the exposed region 701. Which is in the form of a through hole and which extends through the thermally conductive block 510 and the block sleeve 520. In addition, it is aligned with and in communication with the socket 402.

Preferably, the inner cavity of the heat conducting channel 501 is matched with the movable pin 700 inserted in the inner cavity, so that the movable pin 700 can only move up and down along the inner cavity of the heat conducting channel 501 and cannot rotate in the inner cavity of the heat conducting channel 501.

In the present invention, the cross-sectional profile of both the thermally conductive path 501 and the socket 402 are the same. After the plunger 500 is properly filled, the space in the inner cavity of the heat conduction channel 501 is overlapped with the tube cavity area of the side tube 420 between the socket 402 and the through hole provided on the side wall of the side tube 420, so that the movable pin 700 can displace along the inner cavity of the heat conduction channel 501.

Referring to fig. 12 and 13, a further embodiment of a control assembly 600 is provided in this embodiment.

The control assembly 600 includes a control box 610 and a coil box 620. Wherein, the PCB board of the control assembly 600 is installed in the control box 610, and the coil of the control assembly 600 is installed in the coil box 620.

The control box 610 is provided with a detachable box cover, and the box cover covers the box opening of the box body; the bottom wall and the rear wall in the box body are both provided with wire holes; the bottom cover part for sealing the pipe orifice at the outer end of the side pipe 420 extends from the bottom of the box, and through holes for fitting the lug screw holes arranged at the pipe orifice at the outer end of the side pipe 420 are formed in the periphery of the bottom cover part.

Preferably, the box cover and the box opening in the control box 610 are in butt joint in a clamping manner. Wherein, the opening side is seted up the opening groove, makes things convenient for people to sled this lid from this department.

In the present invention, after the cover of the control box 610 is opened, the PCB board may be installed into the control box 610 or the PCB board installed in the control box 610 may be removed.

Preferably, the wire hole arranged on the bottom wall of the control box 610 and the wire led through the hole are sealed by sealant.

In the invention, the wires connected with the output end of the fixed resistor 3 and the wires connected with the external power supply output end pass through the wire holes arranged on the bottom wall of the control box 610 box body and are respectively connected with the corresponding input ports of the PCB in the control box 610 box. The wires connected with the output end of the fixed resistor 3 and the wires connected with the external power supply output end are wires penetrating through wire holes arranged on the bottom wall of the control box 610 box body.

Preferably, the wire hole formed in the rear wall of the control box 610 and the wire led through the hole are sealed by sealant.

In the present invention, the wires for input and output of the coils contained in the control module 600 pass through the wire holes formed in the rear wall of the box body of the control box 610 and are respectively connected to the corresponding ports of the PCB board in the box body of the control box 610. The wires for input and output of the coils included in the control module 600 are wires passing through the wire holes formed in the rear wall of the control box 610.

Preferably, the rear wall of the bottom cover portion of the control box 610 is provided with a protrusion adapted to the outer end nozzle of the side pipe 420.

In the invention, the protruding part arranged on the rear wall surface of the bottom cover part of the control box 610 can be plugged in the pipe orifice at the outer end of the side pipe 420 and is abutted with the outer end surface of the block sleeve 520, so that the plunger 500 is prevented from shaking in the pipe cavity of the side pipe 420. When the protruding portion is completely plugged into the pipe orifice at the outer end of the side pipe 420, the through hole formed at the periphery of the bottom cover portion of the control box 610 is aligned with and communicated with the screw hole of the ear block formed at the pipe orifice at the outer end of the side pipe 420. At this time. The screw is threaded through the through hole, so that the screw is screwed with the screw hole, and the bottom cover part of the control box 610 can be fixedly installed at the pipe orifice of the outer end of the side pipe 420.

The coil box 620 is provided with a detachable box cover, and the box cover covers the box opening of the box; the box cover and the box bottom are provided with a through hole for the running pin 700 to pass through, and the through hole and the annular cavity of the coil in the coil box 620 form a channel for controlling the running pin 700 to pass through; the coil box 620 is also provided with a protruding part which is matched with the hole phase arranged at the end part of the bracket 440. In addition, a side wall of the body of the coil box 620 is adjacent to the rear wall of the control box 610, and extends outwards to form a rib plate fixedly connected with the rear wall of the control box 610, and the side wall is further provided with a wire hole.

Preferably, the box cover and the box opening in the coil box 620 are in butt joint in a clamping manner. Wherein, the opening side is seted up the opening groove, makes things convenient for people to sled this lid from this department.

In the present invention, after the cover in the coil box 620 is opened, the coil may be mounted into the coil box 620 or the coil mounted in the coil box 620 may be removed.

Preferably, the openings provided in the lid and bottom of the coil box 620 are aligned with the sockets 402.

In the present invention, when the control assembly 600 is properly installed, the control channel provided by the coil box 620 is aligned with the socket 402. In addition, the cross-sectional profile of the opening provided in the lid and the socket 402 of the coil box 620 is the same.

Preferably, the protruding portion of the coil box 620 is formed in an "X" shape. The protruding portion is used for being inserted into a hole position arranged at the end of the support 440, screw holes are formed in the outer side of the protruding portion, and the screw holes are respectively located at four ends of the protruding portion. In addition, these screw holes are also provided with shims.

In the present invention, each pad provided to the boss provided to the body of the coil box 620 can be used together with two screw holes of the boss. Thus, the coil case 620 and the bracket 440 may be fixedly installed together by inserting a screw through the spacer and then screwing the screw into the screw hole. The middle part of the gasket is blocked by the corresponding triangular plate at the periphery of the hole site arranged at the end part of the bracket 440, so that the protruding part arranged at the box body of the coil box 620 can be prevented from being separated from the hole site arranged at the end part of the bracket 440.

Preferably, the wire holes formed in the side walls of the coil box 620 are sealed with the wires passing through the holes by sealant.

In the present invention, the wires for input and output of the coils included in the control module 600 pass through the wire holes formed in the side wall of the coil box 620 and the wire holes formed in the rear wall of the box body of the control box 610 in sequence, and then are connected to the corresponding ports of the PCB board in the box of the control box 610. The wires for input and output of the coils included in the control assembly 600 are wires passing through the wire holes formed in the side wall of the coil box 620.

Referring to fig. 14-19, a further version of a wrist 700 is shown in this embodiment.

The loose pin 700 includes a pin housing 710 and a pin core 720.

The head of the pin shell 710 is of a hollow thin shell structure, and the shell wall of the head is uniformly provided with hollowed-out openings. In addition, the shell wall of the head is connected with an outer rod 713 in a straight tubular shape, the lumen of the outer rod 713 is communicated with the inner cavity of the shell wall of the head, and the tail part of the outer rod 713 is adjacent to an exposed area 701. Wherein the outer rod 713 may pass through the channel provided in the coil housing 610, the straight channel provided in the base 400, the heat conductive channel 501 and the bypass pipe 430.

Preferably, the pin housing 710 is made of a material that is resistant to high temperatures, insulating, and heat-insulating.

In the present invention, the pin housing 710 is coated on the outer surface of the pin core 720, and the heat dissipation portion of the pin core 720 can be restricted.

Preferably, the head shell wall of the pin shell 710 is formed of two shells with the mouths thereof being in engagement, and the two shells are an outer top shell 711 and an outer bottom shell 712, respectively.

In the present invention, one of the hollowed-out openings provided in the outer cover 712 communicates with the mouth of the head of the outer rod 713. That is, the edge of the hollowed-out opening is connected with the edge of the head rod opening of the outer rod 713, so that the inner cavity of the outer bottom 712 is communicated with the inner cavity of the outer rod 713.

Preferably, the outer tube surface of the middle of the outer rod 713 is provided with a protrusion for limiting the displacement distance of the movable 700.

In the present invention, the outer rod 713 is adapted to the through-hole control channels provided at the cover and the bottom of the coil box 610, the straight channel provided at the base 400, the heat conduction channel 501 and the bypass pipe 430, so that the outer rod 713 can only pass through the through-hole control channels provided at the cover and the bottom of the coil box 610, the straight channel provided at the base 400, the heat conduction channel 501 and the bypass pipe 430, but cannot rotate therein.

Preferably, the exposed region 701 exposes the slug 725 out of the lumen of the outer rod 713.

In the present invention, by displacement of the outer rod 713, the exposed region 701 can be adjusted to be entirely within the heat conductive channel 501, such that the slug 725 contacts the inner cavity wall of the heat conductive channel 501, and such that the heat conductive block 510 transfers heat to the slug 725 by heat conduction.

The head of the pin core 720 is of a hollow thin shell structure, and the shell wall of the head is uniformly provided with hollowed-out openings. Wherein the outer surface of the shell wall of the head portion is in contact with the inner surface of the shell wall of the head portion of the pin housing 710. Furthermore, an inner rod 723 having a solid rod shape is connected to the wall of the head, and the inner rod 723 is inserted into the lumen of the outer rod 713. The upper shaft of the inner rod 723 is provided with a caulking groove, and the groove is embedded with a core 724 controlled by a coil magnetic field contained in the control assembly 600. The inner rod 723 is provided with a slug 725 at the tail.

Preferably, the pin core 720. A heat conducting material is selected.

In the present invention, the outer surface of the head wall of the pin core 720 is completely adhered to the inner surface of the head wall of the pin housing 710, and other parts of the pin core 720 are covered by the pin housing 710. Therefore, the pin core 720 can transfer its own heat to the outside air only by means of heat radiation through its head housing wall. The hollow holes of the pin core 720 and the pin shell 710 can be used for ventilation, so that heat in the thin shell structure of the head of the movable pin 700 can be dissipated outwards.

Preferably, the head shell wall of the pin core 720 is formed by two shells with two openings, and the two shells are an inner top shell 721 and an inner bottom shell 722 respectively.

In the present invention, the outer wall surface of the inner bottom cover 722 is connected to the head of the inner rod 723 so that the heat of the inner rod 723 can be transferred to the inner bottom cover 722 by heat conduction.

Preferably, the inner rod 723 is a solid straight rod.

In the present invention, the side surface of the rod body at the lower part of the inner rod 723 is attached to the wall surface of the lumen of the outer rod 713, and the two are adhered and fixed by using an adhesive.

Preferably, the iron core 724 is composed of a plurality of straight rods, and the straight rods are sequentially enmeshed to form a straight tube structure, the straight tube structure is completely embedded in an embedding groove formed in the inner rod 723, and the outer side wall surface of the straight tube structure is attached to the lumen wall surface of the outer rod 713.

In the present invention, the plunger 724 is positioned within the annular cavity of the coil contained in the control assembly 600.

When the coil is energized to establish a magnetic field, the magnetic field can be used to drive the plunger 724 to displace in the direction of the head end of the loose pin 700. That is, the movable pin 700 is displaced in synchronization with the whole until the protrusion provided on the outer lever 713 abuts against the edge of the opening provided on the bottom of the coil box 620. At this time, the exposed region 701 adjacent to the tail of the outer rod 713 is entirely within the heat conduction channel 501.

When the coil is de-energized, the magnetic field established when it is energized disappears. At this time, the movable pin 700 is reset under the self weight of the movable pin 700. That is, the slug 725 is offset from the heat transfer channel 501 and no longer contacts the same.

Preferably, the slug 725 is mounted in the exposed area 701 adjacent the tail of the outer rod 713. The inner wall surface of the inner rod 723 is attached to the rear side wall surface of the inner rod, and the outer wall surface thereof is attached to the inner cavity wall surface of the heat conduction channel 501.

In the present invention, the panel 725 is adhesively secured to the inner rod 723 by an adhesive. When the exposed region 701 adjacent to the tail of the outer rod 713 is fully within the heat conductive channel 501, the slug 725 can fully conform to the interior cavity surface of the heat conductive channel 501.

Example two

Based on the first embodiment, a further solution of the plunger 500 is given in this embodiment.

The heat conducting block 510 is a solid cylinder, and two bottom surfaces of the cylinder are respectively an inner end surface and an outer end surface of the heat conducting block 510. Wherein, the inner end surface of the heat conduction block 510 is a cambered surface and can be completely attached to the outer surface of the PTC thermistor 300; the outer end surface of the control box 610 is a plane, and the outer end surface of the block sleeve 520 covered by the control box can be completely abutted against the bottom cover part arranged at the bottom of the control box 610.

Or:

the heat conducting block 510 is a solid elliptic cylinder, and two bottom surfaces of the elliptic cylinder are respectively an inner end surface and an outer end surface of the heat conducting block 510. Wherein, the inner end surface of the heat conduction block 510 is a cambered surface and can be completely attached to the outer surface of the PTC thermistor 300; the outer end surface of the control box 610 is a plane, and the outer end surface of the block sleeve 520 covered by the control box can be completely abutted against the bottom cover part arranged at the bottom of the control box 610.

Or also:

The heat conducting block 510 is a solid polygonal body, and two bottom surfaces of the polygonal body are respectively an inner end surface and an outer end surface of the heat conducting block 510. Wherein, the inner end surface of the heat conduction block 510 is a cambered surface and can be completely attached to the outer surface of the PTC thermistor 300; the outer end surface is a plane, and the block sleeve 520 covered by the plane can be completely abutted against the bottom cover part arranged at the bottom of the control box 610.

Example III

Based on embodiment one, a further version of the loose pin 700 is presented in this embodiment.

The thin shell structure of the head of the loose pin 700 is in the shape of a hollow sphere as a whole, and the center of gravity thereof is positioned on the central axis of the inner rod 723.

Or:

The thin shell structure of the head of the loose pin 700 is generally hollow and ellipsoidal and has a center of gravity on the central axis of the inner rod 723.

Or also:

The thin shell structure of the head of the loose pin 700 is in a hollow polyhedron shape as a whole, and the center of gravity of the thin shell structure is positioned on the central axis of the inner rod 723.

Example IV

Based on embodiment one, a further version of the loose pin 700 is presented in this embodiment.

The rod body below the head of the movable pin 700 is a straight rod with a circular cross section. That is, the outer rod 713 is a straight pipe having a circular cross section; the inner rod 723 is a straight rod having a circular cross section, and a caulking groove provided in the inner rod 723 is provided around the rod circumference of the upper rod body thereof. The iron core 724 is entirely a straight pipe having a circular cross section, and is entirely fitted into a fitting groove provided in the inner rod 723.

Or:

The rod body below the head of the movable pin 700 is a straight rod with an elliptical cross section. That is, the outer rod 713 is a straight pipe having an elliptical cross section; the inner rod 723 is a straight rod having an elliptical cross section, and a caulking groove provided in the inner rod 723 is provided around the rod circumference of the upper rod body thereof. The iron core 724 is entirely a straight pipe having an elliptical cross section, and is entirely fitted into a fitting groove provided in the inner rod 723.

Or also:

The rod body below the head of the movable pin 700 is a straight rod with a polygonal cross section. That is, the outer rod 713 is a straight pipe having a polygonal cross section; the inner rod 723 is a straight rod having a polygonal cross section, and a caulking groove provided in the inner rod 723 is provided around the rod circumference of the upper rod body thereof. The iron core 724 is a straight pipe having a polygonal cross section as a whole, and is completely fitted into a fitting groove provided in the inner rod 723.

Example five

Based on any of the first to fourth embodiments, this embodiment provides a further solution for the loose pin 700.

The outer rod 713 is a single port tube. The head end nozzle of the device is communicated with the inner cavity of the outer cover 712, the exposed area 701 is arranged on the tail side wall of the device, and the tail side wall of the device is also provided with a convex rib 714 opposite to the exposed area 701. Wherein, the top of the rib 714 replaces the protrusion of the outer wall surface of the outer rod 713, and can be used for limiting the displacement distance of the movable pin 700. That is, the insert 725 fully engages the heat transfer channel 501 when the top surface of the bead 714 abuts the rim of the opening provided in the bottom of the coil box 620. In addition, when the opening angle of the exposed region 701 is large, the presence of the ribs 714 can strengthen the firmness of the side wall of the tail of the outer rod 713 opposite to the exposed region 701, reducing the risk of breakage of the outer rod 713 from this side wall.

The socket 402, the heat conducting channel 501 and the bypass pipe 430 are provided with sliding grooves matched with the ribs 714 on the cavity walls thereof so that the ribs 714 can move along the sliding grooves, and the sliding grooves together form a straight groove. The engagement of the straight groove with the ribs 714 prevents rotation of the outer rod 713. In addition, the openings provided in the lid and bottom of the coil box 620 are also provided with slots for the ribs 714, and the slots are aligned with each other but offset from the slots provided in the socket 402 to limit the displacement distance of the movable pin 700.

The slug 725 has an arcuate shape. Which is embedded in the exposed region 701 and whose inner wall surface is entirely fitted to the rear side wall surface of the inner rod 723.

Example six

Based on any of the first to fourth embodiments, this embodiment provides a further solution for the loose pin 700.

The outer rod 713 is a double-ended tube. The head nozzle communicates with the inner cavity of the outer housing 712, while the tail nozzle circumscribes a virtual area as the exposed area 701 to which it is adjacent. Wherein, a pad made of the same material as the outer rod is arranged at the tail end of the virtual area. The gasket is adhesively secured to the trailing end face of the inner rod 723 by an adhesive.

The slug 725 is in the shape of a straight tube. Which is sleeved on the rear of the inner rod 723 and is located in the exposed region 701. In addition, the bottom surface of the gasket 725 is adhered and fixed to the top surface of the gasket at the end of the virtual area circumscribed by the outer rod 713 by using an adhesive.

Based on the above description and the drawings, one skilled in the art will be able to understand and practice the present invention. Furthermore, any non-inventive modifications to the present invention that would not be made by a person skilled in the art without the inventive effort would still fall within the scope of the present invention.

Claims (16)

1. The utility model provides an electromagnetic voltage transformer overvoltage suppression subassembly based on PTC, includes primary harmonic elimination ware (1) of establishing ties between PT high voltage side neutral point and ground point, its characterized in that still includes: the resistor-reducing device (2) and the fixed resistor (3) are connected in parallel with the primary harmonic eliminator (1), the resistor-reducing device (2) and the fixed resistor (3) are connected in series, and the resistor-reducing device (2) is positioned at the output side of the fixed resistor (3);

the primary harmonic eliminator (1) is a flow-sensitive harmonic eliminator with positive temperature coefficient characteristics, the internal resistance core of the primary harmonic eliminator is made of PTC materials, and the external shell of the primary harmonic eliminator is provided with a mounting position for mounting the resistance reducer (2);

the resistor-reducing device (2) comprises:

the plunger (500) is arranged in the installation position of the outer shell of the primary harmonic elimination device (1), the inner end surface of the plunger is in contact with the inner choke core of the primary harmonic elimination device (1) to conduct heat, and the outer end of the plunger is provided with a through hole type heat conduction channel (501);

The control assembly (600) is arranged outside the installation position of the outer shell of the primary harmonic elimination device (1), and comprises a PCB (printed circuit board) which is connected in parallel with the primary harmonic elimination device (1) and connected in series with the fixed resistor (3) and a coil controlled by the circuit of the PCB;

The movable pin (700) is arranged at the installation position of the outer shell of the primary harmonic elimination device (1) and is controlled by the magnetic field of a coil contained in the control assembly (600) to pass through the annular cavity of the coil and the heat conduction channel (501), and the tail part of the movable pin is remained in the heat conduction channel (501) and can contact the plunger (500), so that the heat of the plunger (500) is transferred to the tail part of the movable pin in a heat conduction mode and the heat is radiated to the surrounding air in a heat radiation mode by the head part of the movable pin so as to accelerate the temperature reduction of the inner choke core of the primary harmonic elimination device (1);

The movable pin (700) comprises a pin shell (710) for heat insulation and a pin core (720) for heat dissipation, and the head of the pin core (720) can be contacted with ambient air;

The main body of the pin shell (710) is a straight tubular outer rod (713) capable of passing through the annular cavity of the coil contained in the control assembly (600), the tail part of the outer rod (713) can pass through the heat conduction channel (501), and the tail part of the outer rod (713) is adjacent to an exposure area (701);

The main body of the pin core (720) is an inner rod (723) which can be plugged into the pipe cavity of the outer rod (713), a caulking groove is formed in the upper rod body of the inner rod (723), an iron core (724) controlled by a coil magnetic field contained in the control assembly (600) is embedded in the caulking groove, and an caulking piece (725) exposed at the exposed area (701) is arranged at the tail part of the inner rod (723);

When PT overvoltage is restrained from a peak, the current of a constant value resistor (3) acquired by a PCB (printed circuit board) contained in the control assembly (600) is gradually reduced, a control circuit of the PCB starts to control the coil contained in the control assembly (600) to electrify and establish a magnetic field, the magnetic field is utilized to drive an iron core (724) to displace towards the direction of the head end of a movable pin (700) to enable an exposed area (701) to move to the inner cavity of a heat conducting channel (501), and then an embedded piece (725) is enabled to directly contact with the wall surface of the inner cavity of the heat conducting channel (501) to achieve cooling of the inner blocking core of the primary harmonic eliminator (1).

2. PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 1, characterized in that the primary detuner (1) comprises:

The sleeve (100) is used as an outer shell of the primary harmonic elimination device (1), a lead wire for connecting a PT high-voltage side neutral point is arranged at the top end of the sleeve, a through hole type side opening (101) is formed in the side wall of the sleeve, and the side opening (101) is used as part of an installation position of the outer shell of the primary harmonic elimination device (1);

the top cover (200) is filled in the cylinder cavity at the top of the sleeve (100) and is connected with a wire arranged at the top end of the sleeve (100);

the PTC thermistor (300) is used as an internal choke core of the primary harmonic eliminator (1) to be filled in a barrel cavity of the sleeve (100), the top of the PTC thermistor is provided with a wire connected with the top cover (200), and the bottom of the PTC thermistor is provided with a wire for grounding;

and the base (400) is sleeved on the cylinder body at the bottom of the sleeve (100), and the bottom surface of the inner cavity of the base is connected with a wire arranged at the bottom of the PTC thermistor (300).

3. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 2, wherein:

The sleeve (100) is divided into an outer cylinder (110) and an inner cylinder (120), the outer cylinder (110) is coated on the outer side wall surface of the inner cylinder (120), and the top of the outer cylinder (110) is covered right above the inner cylinder (120);

the conducting wire arranged at the top end of the sleeve (100) passes through the top end of the outer cylinder (110), the outer end of the conducting wire is connected with the neutral point of the PT high-voltage side, and the inner end of the conducting wire is connected with the top cover (200).

4. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 2, wherein:

The top surface of the top cover (200) is provided with a first hole (201) for connecting the inner end of a wire arranged at the top end of the sleeve (100), and the bottom surface of the top cover is provided with a second hole (202) for connecting the wire arranged at the top of the PTC thermistor (300);

the first hole (201) and the second hole (202) are blind hole type threaded holes and are provided with bolts for fastening wires connected with the blind hole type threaded holes.

5. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 2, wherein the base (400) comprises:

The groove drum (410) is sleeved on the bottom cylinder body of the sleeve (100), the side wall of the groove drum is provided with a through hole which is aligned with and communicated with the side hole (101), the bottom surface of the drum cavity of the groove drum is provided with a hole III (401) for connecting a wire arranged at the bottom of the PTC thermistor (300), and the hole III (401) is a blind hole type threaded hole and is provided with a bolt for fastening the wire connected with the hole;

A side pipe (420) which is arranged outside the side wall of the groove drum (410), the pipe orifice at the inner end of the side pipe is aligned with and communicated with the through hole arranged on the side wall of the groove drum (410), a socket (402) for inserting a loose pin (700) is arranged on one side wall of the pipe body, and a through hole opposite to the socket (402) is arranged on the other side wall of the pipe body;

The side pipe (430) is arranged outside the side wall of the side pipe (420), and the pipe orifice of the side pipe is aligned with and communicated with the through hole arranged on the side wall of the side pipe (420);

one end of the bracket (440) is fixed outside the side wall of the base (400), and the other end of the bracket is provided with a hole site for installing the control component (600);

The through hole, the side pipe (420), the side pipe (430), the bracket (440) and the side hole (101) which are arranged on the side wall of the groove cylinder (410) form the whole of the installation position of the outer shell of the primary harmonic elimination device (1).

6. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 5, wherein:

The groove cylinder (410) is a cylinder body with a single cylinder opening;

The side pipe (420) is a double-pipe body;

the bypass pipe (430) is a single-pipe-mouth pipe body;

The hole cavity of the hole site arranged at the end part of the bracket (440) is in an X shape, and the hole is a through hole.

7. The PTC-based electromagnetic voltage transformer overvoltage suppression assembly of claim 5, wherein the plunger (500) comprises:

A heat conduction block (510) which is filled in a channel formed by the side pipe (420), a through hole formed in the side wall of the groove cylinder (410) and the side hole (101), and the inner end surface of which is abutted against the outer side wall surface of the PTC thermistor (300);

A block cover (520) which covers the other surface of the heat conduction block (510) except the inner end surface of the heat conduction block (510);

The heat transfer channel (501) is in the form of a through hole extending through the heat transfer block (510) and block sleeve (520) that can be aligned and in communication with the socket (402).

8. The PTC-based electromagnetic voltage transformer overvoltage suppression assembly of claim 5, wherein the control assembly (600) comprises:

A control box (610), wherein a PCB (printed Circuit Board) contained in the control assembly (600) is arranged in the control box, and a bottom cover part for sealing an orifice at the outer end of the side pipe (420) extends from the bottom of the control box;

The coil box (620), the coil that control assembly (600) contains installs in its box, and its box body has offered the opening that supplies loose pin (700) to pass, and this opening constitutes a passageway that is used for controlling loose pin (700) to pass and this passageway aligns with socket (402) jointly with the ring chamber of this coil, and its box body lateral wall is equipped with the bellying that sets up the hole phase adaptation with support (440) tip.

9. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to any one of claims 5-8, wherein:

the head of the pin shell (710) is of a hollow thin shell structure, hollow openings are uniformly formed in the shell wall, and the outer part of the shell wall of the head is connected with the head end of the outer rod (713);

The head of the pin core (720) is of a hollow thin shell structure, the outer surface of the shell wall is attached to the inner surface of the head shell wall of the pin shell (710), and the outer surface of the head shell wall is connected with the head end of the inner rod (723).

10. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 9, wherein:

The head shell wall of the pin shell (710) is composed of two cover bodies with matched cover openings, and the two cover bodies are an outer top cover (711) and an outer bottom cover (712) respectively;

The head end of the outer rod (713) is connected with the outer cover (712) and the inner cavities of the outer rod and the outer cover are communicated.

11. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 9, wherein:

the head shell wall of the pin core (720) is composed of two cover bodies with matched cover openings, and the two cover bodies are an inner top cover (721) and an inner bottom cover (722) respectively;

the head of the inner rod (723) is connected with the cover body of the inner bottom cover (722);

The iron core (724) can be plugged into the inner cavity of the outer rod (713);

The inner wall surface of the embedded piece (725) is attached to the tail side wall surface of the inner rod (723), and the outer wall surface of the embedded piece can be contacted with the inner cavity wall surface of the heat conducting channel (501).

12. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 10, wherein:

The outer rod (713) is a single-port tube body, the tube orifice of the outer rod is connected with the outer bottom cover (712) and is communicated with the inner cavities of the outer rod and the outer bottom cover, the side wall of the tail of the outer rod is provided with a through port serving as an exposure area (701), and the side wall of the tail of the outer rod is also provided with a convex rib (714) opposite to the through port.

13. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 12, wherein:

the socket (402), the heat conduction channel (501) and the bypass pipe (430) are provided with sliding grooves matched with the convex ribs (714) on the inner cavity wall surfaces.

14. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 12, wherein:

The embedded piece (725) is matched with a through hole arranged on the side wall of the tail part of the outer rod (713).

15. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 10, wherein:

the outer rod (713) is a double-mouth tube body, a head end tube orifice of the outer rod (713) is connected with the outer cover (712) and communicated with the inner cavities of the outer rod and the outer cover, a section of virtual area is externally connected with a tail end tube orifice of the outer rod to serve as an exposure area (701), and a gasket which is the same as the outer rod (713) in material is arranged at the tail end of the virtual area and is attached to the end face of the tail part of the inner rod (723).

16. A PTC-based electromagnetic voltage transformer overvoltage suppression assembly according to claim 15, wherein:

The embedded piece (725) is in a round straight tube shape, is sleeved at the tail part of the inner rod (723) and is matched with a virtual area circumscribed by a pipe orifice at the tail end of the outer rod (713).