Monitoring circuit of lightning arrester and monitoring method thereof

Abstract

The invention provides a monitoring circuit of a lightning arrester and a monitoring method thereof, and belongs to the technical field of lightning arrester monitoring, and under the condition that a target lightning arrester is subjected to lightning impulse or abnormal overvoltage occurs in a power grid, the current released by the target lightning arrester is greater than a first preset current, so that a first conduction unit is conducted. Furthermore, the second conduction unit and the first conduction unit are connected in parallel, so that the current flowing through the first conduction unit can be ensured to be smaller than the breakdown current of the first conduction unit, the first conduction unit is prevented from being broken down, and the reliability, the stability and the safety of the lightning arrester monitoring circuit are improved. According to the monitoring circuit of the lightning arrester, a first conduction unit is conducted under the condition that alternating current released by a target lightning arrester is larger than first preset current. And the second conduction unit is conducted under the condition that the alternating current released by the target lightning arrester is greater than the third preset current. The counting unit counts the number of actions of the target lightning arrester.

Description

Technical Field

[0001] The present application relates to the technical field of lightning arrester monitoring, and in particular to a lightning arrester monitoring circuit and a monitoring method thereof. Background Art

[0002] In the power system, the main function of the arrester is to protect the power equipment, prevent the line from being affected by lightning strikes, maintain the insulation strength of the power equipment, extend the service life of the power equipment, and thus improve the reliability of the power system. By monitoring the operating status of the arrester, you can understand the operating status of the arrester in real time, detect potential faults or aging problems early, thereby improving the reliability of the equipment, and provide early warning information to promptly detect the performance degradation or aging signs of the arrester, extend the life of the arrester and other power equipment, and improve the availability of the power system. By monitoring and recording the operating status of the arrester, operation and maintenance personnel can formulate a more scientific and efficient maintenance plan. Reduce unplanned downtime and improve the operating efficiency of the power system.

[0003] Most arrester monitoring uses arrester monitors to monitor the arrester leakage current and the number of operations. The arrester monitor can monitor the operating current passing through the arrester under the operating voltage, and then determine whether the arrester is damp or the components are abnormal. The number of arrester operations can be recorded, which helps to understand the operating status and life of the arrester. By online monitoring of the continuous current and number of operations of the arrester, abnormal conditions of the arrester can be discovered and handled in a timely manner, increasing the safety of power grid operation.

[0004] However, in the conventional technology, when the square wave current of the arrester is large, the monitor cannot accurately monitor the number of times the arrester operates, and may even damage the arrester monitor, thereby reducing the precision and accuracy of the monitoring results. Summary of the invention

[0005] Based on this, it is necessary to provide a monitoring circuit and a monitoring method for a lightning arrester in order to solve the above technical problems.

[0006] In a first aspect, the present application provides a monitoring circuit for a lightning arrester, comprising:

[0007] A first conducting unit, one end of which is used to obtain the alternating current released by the target lightning arrester, and the other end of which is used for grounding, wherein the conduction current of the first conducting unit is a first preset current, and the breakdown current of the first conducting unit is a second preset current. When the alternating current released by the target lightning arrester is greater than the first preset current, the first conducting unit is turned on, and the second preset current is greater than the first preset current;

[0008] a second conducting unit connected in parallel with the first conducting unit, and the second conducting unit is turned on when the alternating current released by the target lightning arrester is greater than a third preset current, wherein the second preset current is greater than the third preset current;

[0009] A counting unit, wherein the input end of the counting unit is connected to the output end of the first conduction unit and the output end of the second conduction unit, and when at least one of the first conduction unit and the second conduction unit is turned on, the counting unit is used to count the number of operations of the target lightning arrester according to the alternating current released by the target lightning arrester.

[0010] In one embodiment, the monitoring circuit of the arrester further includes:

[0011] A current detection unit is connected in parallel with the first conduction unit and is used to detect the current value of the alternating current released by the target lightning arrester.

[0012] In one embodiment, the current detection unit includes:

[0013] a first current limiting resistor, one end of which is used to obtain the alternating current released by the target lightning arrester;

[0014] a first rectifier bridge, wherein an AC input end of the first rectifier bridge is electrically connected to the other end of the first current limiting resistor;

[0015] A second current limiting resistor, wherein an input end of the second current limiting resistor is electrically connected to a DC output end of the first rectifier bridge;

[0016] An ammeter, wherein the input end of the ammeter is electrically connected to the output end of the second current limiting resistor, and the output end of the ammeter is electrically connected to the DC input end of the first rectifier bridge, wherein the AC output end of the first rectifier bridge is grounded.

[0017] In one embodiment, the maximum detected current value of the ammeter is less than the first preset current.

[0018] In one embodiment, the counting unit comprises:

[0019] An energy transformer, wherein a first input end of the energy transformer is electrically connected to an output end of the first conduction unit and an output end of the second conduction unit, and the energy transformer is used to convert alternating current into direct current;

[0020] A second rectifier bridge, wherein an AC input end of the second rectifier bridge is electrically connected to a first output end of the energy taking transformer;

[0021] A counter is used to count the number of times the target lightning arrester is operated according to the DC power output by the energy taking transformer, the input end of the counter is electrically connected to the DC output end of the second rectifier bridge, the output end of the counter is electrically connected to the DC input end of the second rectifier bridge, and the AC output end of the second rectifier bridge is grounded.

[0022] In one of the embodiments, the first conduction unit includes a protection resistor, and a resistance value of the protection resistor is related to a current value of the alternating current released by the target lightning arrester.

[0023] In one of the embodiments, the second conduction unit includes a discharge gap, and when the current value of the alternating current released by the target lightning arrester is greater than a third preset current, the discharge gap is used to conduct the alternating current released by the target lightning arrester to the ground.

[0024] In one embodiment, a difference between the third preset current and the second preset current is a first difference, and the third preset current is three times the first difference.

[0025] In one embodiment, the monitoring circuit of the arrester further includes:

[0026] A first capacitor, one end of the first capacitor is electrically connected to the DC output end of the first rectifier bridge, and the other end of the first capacitor is grounded via the DC output end of the first rectifier bridge;

[0027] A second capacitor is connected in parallel with the counter.

[0028] In a second aspect, the present application provides a lightning arrester and a monitoring circuit, which are applied to the monitoring circuit of the lightning arrester described in any one of the first aspects, and the method includes:

[0029] Acquire the AC power released by the target lightning arrester;

[0030] When the AC current released by the target lightning arrester is greater than a first preset current, turning on a first conducting unit, wherein a breakdown current of the first conducting unit is a second preset current, and the second preset current is greater than the first preset current;

[0031] When the AC current released by the target lightning arrester is greater than a third preset current, turning on the second conducting unit, wherein the second conducting unit is connected in parallel with the first conducting unit, and the second preset current is greater than the third preset current;

[0032] When at least one of the first conducting unit and the second conducting unit is turned on, the number of operations of the target lightning arrester is counted according to the AC power released by the target lightning arrester.

[0033] The monitoring circuit and monitoring method of the lightning arrester provided by the embodiment of the present application obtain the alternating current released by the target lightning arrester through one end of the first conduction unit, and control the conduction state of the first conduction unit according to the alternating current released by the target lightning arrester. In the case where the target lightning arrester is subjected to lightning strike or abnormal overvoltage occurs in the power grid, the current released by the target lightning arrester is greater than the first preset current, so that the first conduction unit is turned on. Further, by setting the second conduction unit in parallel with the first conduction unit, in the case where the alternating current released by the target lightning arrester is greater than the third preset current, the second conduction unit is controlled to be turned on, so that the second conduction unit forms a shunt to the first conduction unit, thereby reducing the current on the first conduction unit, and facilitating the control of the current flowing through the first conduction unit to be less than the second preset current. Therefore, it can be ensured that the current flowing through the first conduction unit is less than the breakdown current of the first conduction unit, avoiding the first conduction unit from being broken down, and improving the reliability, stability and safety of the lightning arrester monitoring circuit. At the same time, by setting the counting unit at the output end of the first conduction unit and the second conduction unit, the conduction times can be recorded when at least one of the first conduction unit and the second conduction unit is in the conduction state, thereby obtaining the number of times the lightning arrester is in an abnormally high voltage state, and timely obtaining the status information of the lightning arrester. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the conventional technology, the drawings required for use in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0035] FIG1 is a schematic circuit diagram of a monitoring circuit of a lightning arrester provided in an embodiment of the present application;

[0036] FIG. 2 is a flow chart of a method for monitoring a lightning arrester provided in an embodiment of the present application.

[0037] Description of reference numerals:

[0038] 100, first conduction unit; 200, second conduction unit; 300, counting unit; 301, energy extraction transformer; 302, second rectifier bridge; 303, counter; 400, current detection unit; 401, first rectifier bridge; 402, ammeter; 500, first interface. DETAILED DESCRIPTION

[0039] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0041] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that when the terms "consisting of" and / or "comprising" are used in this specification, the presence of the features, integers, elements and / or components may be determined, but the presence or addition of one or more other features, integers, elements, components and / or groups is not excluded. At the same time, when used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0042] In the power system, the main function of the arrester is to protect the power equipment, prevent the line from being affected by lightning strikes, maintain the insulation strength of the power equipment, extend the service life of the power equipment, and thus improve the reliability of the power system. Under the action of long-term working voltage, the current flowing through the metal oxide arrester is only at the microampere level. The metal oxide arrester deteriorates due to long-term direct exposure to the power frequency voltage, causing changes in the resistance characteristics of the metal oxide arrester and an increase in the total current. When the metal oxide arrester has a poor structure and is not tightly sealed, causing the internal components and resistors of the arrester to be damp, it will also lead to an increase in the total current of the metal oxide arrester in operation, thereby reducing the reliability of the arrester. In addition, due to the limitations of the arrester resistor production process, there are differences in the energy absorption capacity of the resistor, which causes some resistors to break down when the arrester absorbs operating overvoltage or atmospheric overvoltage energy during operation, resulting in a decrease in the equivalent resistance of the arrester, which increases the energy absorbed when it is subsequently subjected to overvoltage, aggravates the degradation of the arrester, and increases the total current of the metal oxide arrester in operation.

[0043] By monitoring the operating status of the arrester, the operating status of the arrester can be understood in real time, potential faults or aging problems can be discovered early, thereby improving the reliability of the equipment, providing early warning information, timely discovering the performance degradation or aging signs of the arrester, extending the life of the arrester and other power equipment, and improving the availability of the power system. By monitoring and recording the operating status of the arrester, the operation and maintenance personnel can formulate a more scientific and efficient maintenance plan. Reduce unplanned downtime and improve the operating efficiency of the power system. At present, the arrester monitoring mostly uses the arrester monitor to monitor the arrester leakage current and the number of actions. The arrester monitor can monitor the operating current passing through the arrester under the operating voltage, and then judge whether the arrester is damp inside, whether the components are abnormal, etc. The number of actions of the arrester can be recorded, which helps to understand the operating status and life of the arrester. By online monitoring of the continuous current and the number of actions of the arrester, the abnormal situation of the arrester can be discovered and handled in time, and the safety of the power grid operation can be increased.

[0044] However, in traditional technology, arrester monitors usually use multiple resistors in parallel to improve square wave current capacity, or discharge the arrester's operating current through a discharge gap structure. Monitors that use multiple resistors in parallel to improve current capacity require the mixing of multiple raw materials and multiple processes to produce oxide resistors, which results in differences in resistors, resulting in differences in the energy absorption capacity of the resistors, and thus differences in volt-ampere characteristics. Therefore, it is necessary to subsequently match the volt-ampere characteristics of the resistors, which increases a lot of work and leads to low production efficiency. Arrester monitors that use a discharge gap structure mostly use high-temperature resistant metals for the gap electrodes. Since the temperatures of the two electrodes are different during the discharge gap, and far exceed the melting point of the electrode material, multiple gap discharges cause the gap electrode material to burn, causing changes in the uniformity of the gap electric field, which in turn causes the gap breakdown voltage to be unstable. In addition, the arc temperature is much higher than the melting point of the electrode material. The discharge gap will melt the ferromagnetic components in the electrode material. After the monitor discharge gap discharges multiple times, the gap distance increases, which increases the breakdown voltage, posing a threat to the leakage current loop and even damaging the leakage current measurement loop. It will also delay the gap breakdown time when the arrester is activated, reduce the energy flowing through the current transformer, and reduce the energy transferred by the current transformer. The monitor cannot accurately monitor the number of times the arrester is activated, and may even cause damage to the arrester monitor, thereby reducing the precision and accuracy of the monitoring results.

[0045] The embodiment of the present application provides a monitoring circuit of a lightning arrester, please refer to FIG1, the monitoring circuit of the lightning arrester includes: a first conduction unit 100, a second conduction unit 200 and a counting unit 300. One end of the first conduction unit 100 is used to obtain the alternating current released by the target lightning arrester, and the other end is used for grounding, wherein the conduction current of the first conduction unit 100 is a first preset current, and the breakdown current of the first conduction unit 100 is a second preset current. When the alternating current released by the target lightning arrester is greater than the first preset current, the first conduction unit 100 is turned on, and the second preset current is greater than the first preset current. The second conduction unit 200 is connected in parallel with the first conduction unit 100, and when the alternating current released by the target lightning arrester is greater than the third preset current, the second conduction unit 200 is turned on, wherein the second preset current is greater than the third preset current. The input end of the counting unit 300 is connected to the output end of the first conduction unit 100 and the output end of the second conduction unit 200. When at least one of the first conduction unit 100 and the second conduction unit 200 is turned on, the counting unit 300 is used to count the number of operations of the target lightning arrester according to the alternating current released by the target lightning arrester.

[0046] Exemplarily, the first preset current may be set according to actual conditions of the first conduction unit 100 .

[0047] Exemplarily, the other end of the first conduction unit 100 is grounded, and when the first conduction unit 100 is turned on, the release current flowing through the first conduction unit 100 can be grounded.

[0048] Exemplarily, the second preset current is the breakdown current of the first conduction unit 100 , and a suitable first conduction unit 100 can be selected according to the second preset current to ensure that the first conduction unit 100 is not damaged, thereby improving the reliability of the monitoring circuit of the arrester.

[0049] Exemplarily, the third preset current can be set according to the second preset current. By setting the third preset current to be smaller than the second preset current, when the AC current released by the target lightning arrester is too large, the second conduction unit 200 is turned on to protect the first conduction unit 100 from being broken down.

[0050] The monitoring circuit of the lightning arrester provided in the embodiment of the present application obtains the alternating current released by the target lightning arrester through one end of the first conduction unit 100, and controls the conduction state of the first conduction unit 100 according to the alternating current released by the target lightning arrester. In the case where the target lightning arrester is subjected to lightning strike or abnormal overvoltage occurs in the power grid, the current released by the target lightning arrester is greater than the first preset current, so that the first conduction unit 100 is turned on. Further, by setting the second conduction unit 200 and the first conduction unit 100 in parallel, in the case where the alternating current released by the target lightning arrester is greater than the third preset current, the second conduction unit 200 is controlled to be turned on, so that the second conduction unit 200 forms a shunt to the first conduction unit 100, thereby reducing the current on the first conduction unit 100, and facilitating the control of the current flowing through the first conduction unit 100 to be less than the second preset current. Therefore, it can be ensured that the current flowing through the first conduction unit 100 is less than the breakdown current of the first conduction unit 100, avoiding the first conduction unit 100 from being broken down, and improving the reliability, stability and safety of the lightning arrester monitoring circuit. At the same time, by setting a counting unit at the output end of the first conduction unit 100 and the second conduction unit 200, the conduction times can be recorded when at least one of the first conduction unit 100 and the second conduction unit 200 is in the conduction state, and then the number of times the lightning arrester is in an abnormally high voltage state can be obtained, and the status information of the lightning arrester can be obtained in time.

[0051] In some embodiments, please continue to refer to FIG. 1 , the monitoring circuit of the lightning arrester further includes: a current detection unit 400 connected in parallel with the first conduction unit 100 and used to detect the current value of the alternating current released by the target lightning arrester.

[0052] In the monitoring circuit of the lightning arrester provided in the embodiment of the present application, the current detection unit 400 can detect the AC value released by the target lightning arrester, monitor the AC released by the target lightning arrester in real time, and then monitor the operating state of the target lightning arrester. The current detection unit 400 is connected in parallel with the first conduction unit 100. When the first conduction unit 100 is turned on, the current detection unit 400 can be prevented from being damaged due to excessive current, thereby improving the accuracy and objectivity of the measurement result of the current detection unit 400, improving the diversity and comprehensiveness of the monitoring result of the monitoring circuit of the lightning arrester, and then improving the accuracy and reliability of the monitoring circuit of the lightning arrester.

[0053] In some embodiments, please continue to refer to Figure 1, the current detection unit 400 includes: a first current limiting resistor R1, a first rectifier bridge 401, a second current limiting resistor R2 and an ammeter 402, and the input end of the first current limiting resistor R1 is used to obtain the AC released by the target lightning arrester. The AC input end of the first rectifier bridge 401 is electrically connected to the output end of the first current limiting resistor R1. The input end of the second current limiting resistor R2 is electrically connected to the DC output end of the first rectifier bridge 401. The input end of the ammeter 402 is electrically connected to the output end of the second current limiting resistor R2, and after the output end of the ammeter 402 is connected to the DC input end of the first rectifier bridge 401, the AC output end of the first rectifier bridge 401 is grounded.

[0054] Exemplarily, the measuring range of the ammeter 402 may be selected according to the type of the target lightning arrester, and the resistance values ​​of the first current limiting resistor R1 and the second current limiting resistor R2 may be set according to the measuring range of the ammeter 402 .

[0055] In the monitoring circuit of the lightning arrester provided in the embodiment of the present application, the first current limiting resistor R1 and the second current resistor can ensure that the ammeter 402 will not be damaged due to excessive current. The first rectifier bridge 401 can convert the AC current released by the target lightning arrester into a DC current, and then the current value is measured by the ammeter 402. The first rectifier bridge 401 can also cooperate with the filter circuit to reduce the voltage fluctuation and provide a relatively stable DC current for the ammeter 402, thereby improving the accuracy and objectivity of the monitoring results of the monitoring circuit of the lightning arrester. The DC input terminal of the first rectifier bridge 401 is grounded, which can realize the grounding of the AC released by the target lightning arrester.

[0056] In some embodiments, the maximum detection current value of the ammeter 402 is less than the first preset current.

[0057] In the monitoring circuit of the lightning arrester provided in the embodiment of the present application, the maximum detection current value of the ammeter 402 is less than the first preset current value. When the first conduction unit 100 is turned on, the ammeter 402 is in a fully biased state, so that the conduction condition of the first conduction unit 100 can be monitored through the reading of the ammeter 402.

[0058] In some embodiments, please continue to refer to FIG. 1 , the counting unit 300 includes: an energy-taking transformer 301, a second rectifier bridge 302, and a counter 303. The first input end of the energy-taking transformer 301 is electrically connected to the output end of the first conduction unit 100 and the output end of the second conduction unit 200, and the energy-taking transformer 301 is used to convert AC power into DC power. The AC input end of the second rectifier bridge 302 is electrically connected to the first output end of the energy-taking transformer 301. The counter 303 is used to count the number of actions of the target lightning arrester according to the DC power output by the energy-taking transformer. The input end of the counter is electrically connected to the DC output end of the second rectifier bridge 302, the output end of the counter 303 is electrically connected to the DC input end of the second rectifier bridge 302, and the AC output end of the second rectifier bridge 302 is grounded.

[0059] Exemplarily, the energy taking transformer 301 utilizes the principle of electromagnetic induction to transfer the energy in the high-voltage circuit to the AC input end of the second rectifier bridge 302 through the action of a transformer, and the energy taking transformer 301 can also convert the high-power electrical energy in the high-voltage circuit into low-power electrical energy, thereby providing low-power electrical energy for the counter 303, thereby preventing the counter 303 from being damaged due to excessive power.

[0060] Exemplarily, the second rectifier bridge 302 can convert the AC current released by the target lightning arrester into a DC current, so that the counter 303 counts the number of actions of the target lightning arrester, and can monitor the operating state of the target lightning arrester in real time. The first rectifier bridge 401 can also cooperate with the filter circuit to reduce the voltage fluctuation and provide a relatively stable DC current for the counter 303, thereby improving the accuracy and objectivity of the monitoring results of the monitoring circuit of the lightning arrester. The second input terminal of the rectifier bridge is grounded, which can realize the grounding of the AC released by the target lightning arrester.

[0061] Exemplarily, the types of counter 303 may include but are not limited to electronic counter 303 and mechanical counter 303 .

[0062] The monitoring circuit of the lightning arrester provided in the embodiment of the present application can realize accurate monitoring of the number of actions of the target lightning arrester by the monitoring circuit of the lightning arrester by setting the energy taking transformer 301, the second rectifier bridge 302 and the counter 303 in the counting unit 300, thereby obtaining the operating information of the target lightning arrester in real time.

[0063] In some embodiments, please continue to refer to FIG. 1 , the first conduction unit 100 includes a protection resistor R0 , and the resistance value of the protection resistor R0 is related to the current value of the alternating current released by the target lightning arrester.

[0064] Exemplarily, the protection resistor R0 can distribute the voltage of the current detection unit 400, and the voltage distribution can be achieved by using the protection resistors R0 with different resistance values. The protection resistor R0 can also be used to limit the overvoltage of the target lightning arrester caused by lightning strikes or power grid fluctuations.

[0065] The monitoring circuit of the lightning arrester provided in the embodiment of the present application can limit the overvoltage of the target lightning arrester caused by lightning strikes or grid fluctuations while distributing the voltage of the current detection unit 400 by setting the protection resistor R0, thereby improving the reliability and objectivity of the monitoring circuit of the lightning arrester.

[0066] In some embodiments, please continue to refer to FIG. 1 , the second conduction unit 200 includes a discharge gap, and when the current value of the AC released by the target arrester is greater than the third preset current, the discharge gap is used to conduct the AC released by the target arrester to the ground.

[0067] For example, the discharge gap is mainly composed of two metal bars separated by a certain distance. When the AC released by the target arrester has a transient overcurrent, the air between the two metal bars breaks down to form a discharge channel, which guides the overcurrent into the ground, thereby protecting other devices in the circuit.

[0068] The monitoring circuit of the lightning arrester provided in the embodiment of the present application can guide the overcurrent into the ground when a transient overcurrent occurs in the AC power released by the target lightning arrester by setting a discharge gap, thereby protecting the current detection unit 400 and the first on-resistance in the circuit, thereby improving the reliability of the monitoring circuit of the lightning arrester.

[0069] In some embodiments, a difference between the third preset current and the second preset current is a first difference, and the third preset current is three times the first difference.

[0070] Exemplarily, the difference between the third preset current and the second preset current is the first difference, and the third preset current is three times the first difference. For example, when the second preset current is 2000A, the third preset current is 1500A.

[0071] The monitoring circuit of the lightning arrester provided in the embodiment of the present application can achieve that the second conduction unit 200 is turned on when the first conduction unit 100 is not broken down, by setting the third preset current to three times the first difference, thereby achieving voltage division for the first conduction unit 100, preventing the first conduction unit 100 from being broken down due to excessive release current of the target lightning arrester, thereby improving the reliability of the monitoring circuit of the lightning arrester.

[0072] In some embodiments, please continue to refer to FIG. 1 , the monitoring circuit of the lightning arrester further includes: a first capacitor C1 and a second capacitor C2, the input end of the first capacitor C1 is electrically connected to the DC output end of the first rectifier bridge 401, and the output end of the first capacitor C1 is grounded via the DC output end of the first rectifier bridge 401. The second capacitor C2 is connected in parallel to the counter 303.

[0073] It should be noted that after the monitoring circuit of the lightning arrester converts AC power into DC power through the first rectifier bridge 401 and the second rectifier bridge 302, the output DC power will contain AC ripple. The first capacitor C1 and the second capacitor C2 can smooth the rectified pulsating DC power and reduce the AC ripple, making the output voltage smoother. By storing electrical energy in the circuit and releasing it when the voltage is at a low point, the voltage fluctuation is balanced.

[0074] The monitoring circuit of the lightning arrester provided in the embodiment of the present application can filter the rectified current by setting the first capacitor C1 and the second capacitor C2, and the electric energy after filtering passes through the current detection unit 400, which can improve the accuracy of detecting the current released by the target lightning arrester. The electric energy after filtering passes through the counting unit 300, which can improve the accuracy and objectivity of detecting the overvoltage current released by the target lightning arrester.

[0075] It should be noted that, referring to FIG. 1 , the monitoring circuit of the lightning arrester may further include a first interface 500 , and the first interface 500 is connected to the target lightning arrester.

[0076] The present application embodiment provides a method for monitoring a lightning arrester. Please refer to FIG. 2. The method is applied to the monitoring circuit of the lightning arrester in any one of the above embodiments. The method for monitoring the lightning arrester includes:

[0077] S11: Acquire the AC power released by the target lightning arrester.

[0078] S12: When the alternating current released by the target lightning arrester is greater than the first preset current, turning on the first conduction unit, wherein the breakdown current of the first conduction unit is the second preset current, and the second preset current is greater than the first preset current.

[0079] S13: When the AC current released by the target lightning arrester is greater than a third preset current, turning on the second conduction unit, wherein the second conduction unit is connected in parallel with the first conduction unit, and the second preset current is greater than the third preset current.

[0080] S14: When at least one of the first conducting unit and the second conducting unit is conducting, the number of operations of the target lightning arrester is counted according to the AC power released by the target lightning arrester.

[0081] The control method of the DC transmission drive circuit provided in the embodiment of the present application obtains the AC released by the target lightning arrester through one end of the first conduction unit, and controls the conduction state of the first conduction unit according to the AC released by the target lightning arrester. When the target lightning arrester is subjected to lightning strike or abnormal overvoltage occurs in the power grid, the current released by the target lightning arrester is greater than the first preset current, so that the first conduction unit is turned on. Further, by setting the second conduction unit in parallel with the first conduction unit, when the AC released by the target lightning arrester is greater than the third preset current, the second conduction unit is controlled to be turned on, so that the second conduction unit forms a shunt to the first conduction unit, thereby reducing the current on the first conduction unit, and facilitating the control of the current flowing through the first conduction unit to be less than the second preset current. Therefore, it can be ensured that the current flowing through the first conduction unit is less than the breakdown current of the first conduction unit, avoiding the breakdown of the first conduction unit, and improving the reliability, stability and safety of the arrester monitoring circuit. At the same time, by setting the counting unit at the output end of the first conduction unit and the second conduction unit, the conduction times can be recorded when at least one of the first conduction unit and the second conduction unit is in the conduction state, thereby obtaining the number of times the lightning arrester is in an abnormally high voltage state, and timely obtaining the status information of the lightning arrester.

[0082] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features of the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0083] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A monitoring circuit for a lightning arrester, characterized in that: include: A first conducting unit, one end of which is used to obtain the alternating current released by the target lightning arrester, and the other end of which is used for grounding, wherein the conduction current of the first conducting unit is a first preset current, and the breakdown current of the first conducting unit is a second preset current. When the alternating current released by the target lightning arrester is greater than the first preset current, the first conducting unit is turned on, and the second preset current is greater than the first preset current; a second conducting unit connected in parallel with the first conducting unit, and the second conducting unit is turned on when the alternating current released by the target lightning arrester is greater than a third preset current, wherein the second preset current is greater than the third preset current; A counting unit, wherein the input end of the counting unit is connected to the output end of the first conduction unit and the output end of the second conduction unit, and when at least one of the first conduction unit and the second conduction unit is turned on, the counting unit is used to count the number of operations of the target lightning arrester according to the alternating current released by the target lightning arrester.

2. The monitoring circuit of the arrester according to claim 1, characterized in that: Also includes: A current detection unit is connected in parallel with the first conduction unit and is used to detect the current value of the alternating current released by the target lightning arrester.

3. The monitoring circuit of the arrester according to claim 2, characterized in that: The current detection unit comprises: a first current limiting resistor, one end of which is used to obtain the alternating current released by the target lightning arrester; a first rectifier bridge, wherein an AC input end of the first rectifier bridge is electrically connected to the other end of the first current limiting resistor; a second current limiting resistor, wherein an input end of the second current limiting resistor is electrically connected to a DC output end of the first rectifier bridge; An ammeter, wherein the input end of the ammeter is electrically connected to the output end of the second current limiting resistor, and the output end of the ammeter is electrically connected to the DC input end of the first rectifier bridge, wherein the AC output end of the first rectifier bridge is grounded.

4. The monitoring circuit of the arrester according to claim 3, characterized in that: The maximum detection current value of the ammeter is less than the first preset current.

5. The monitoring circuit of the arrester according to claim 3, characterized in that: The counting unit comprises: An energy transformer, wherein a first input end of the energy transformer is electrically connected to an output end of the first conduction unit and an output end of the second conduction unit, and the energy transformer is used to convert alternating current into direct current; A second rectifier bridge, wherein an AC input end of the second rectifier bridge is electrically connected to a first output end of the energy taking transformer; A counter is used to count the number of times the target lightning arrester is operated according to the DC power output by the energy taking transformer, the input end of the counter is electrically connected to the DC output end of the second rectifier bridge, the output end of the counter is electrically connected to the DC input end of the second rectifier bridge, and the AC output end of the second rectifier bridge is grounded.

6. The monitoring circuit of the arrester according to claim 1, characterized in that: The first conducting unit includes a protection resistor, and a resistance value of the protection resistor is related to a current value of the alternating current released by the target lightning arrester.

7. The monitoring circuit of the arrester according to claim 1, characterized in that: The second conduction unit includes a discharge gap. When the current value of the alternating current released by the target arrester is greater than the third preset current, the discharge gap is used to conduct the alternating current released by the target arrester to the ground.

8. The monitoring circuit of the arrester according to claim 1, characterized in that: The difference between the third preset current and the second preset current is a first difference, and the third preset current is three times the first difference.

9. The monitoring circuit of the arrester according to claim 5, characterized in that: Also includes: A first capacitor, one end of the first capacitor is electrically connected to the DC output end of the first rectifier bridge, and the other end of the first capacitor is grounded via the DC output end of the first rectifier bridge; A second capacitor is connected in parallel with the counter.

10. A method for monitoring a lightning arrester, characterized in that: A monitoring circuit for a lightning arrester according to any one of claims 1 to 9, the method comprising: Acquire the AC power released by the target lightning arrester; When the AC current released by the target lightning arrester is greater than a first preset current, turning on a first conducting unit, wherein a breakdown current of the first conducting unit is a second preset current, and the second preset current is greater than the first preset current; When the AC current released by the target lightning arrester is greater than a third preset current, turning on a second conducting unit, wherein the second conducting unit is connected in parallel with the first conducting unit, and the second preset current is greater than the third preset current; When at least one of the first conducting unit and the second conducting unit is turned on, the number of operations of the target lightning arrester is counted according to the AC power released by the target lightning arrester.

Images