Operation lightning arrester quality monitoring method, system and device

Abstract

The invention discloses a method, system and device for monitoring the quality of an operating lightning arrester, and the method comprises the steps: collecting a lightning current, a leakage current, the temperature of the lightning arrester and the environment temperature during lightning stroke, evaluating the residual life of the lightning arrester through the lightning current, and achieving the quality monitoring of the operating lightning arrester based on the residual life, the leakage current, the temperature of the lightning arrester and the environment temperature. Healthy operation of the lightning arrester can be ensured, safe and reliable operation of a distribution line can be ensured, and great economic value and social benefit are achieved.

Description

Technical Field

[0001] The invention relates to a method, system and device for monitoring the quality of a running lightning arrester, and belongs to the field of online monitoring of lightning arresters. Background Art

[0002] Installing zinc oxide arresters is an important measure to protect the insulated lines of 10kV distribution networks from lightning overvoltage. For a long time, there have been tens of thousands of arresters on distribution lines. Currently, there are no monitoring devices for zinc oxide arresters on the lines or only mechanical lightning counters, so it is impossible to monitor the quality of the arresters in operation. Summary of the invention

[0003] The present invention provides a method, system and device for monitoring the quality of an operating lightning arrester, which solve the problems disclosed in the background technology.

[0004] According to one aspect of the present disclosure, a method for monitoring the quality of an operating lightning arrester is provided, comprising: If the arrester is not struck by lightning at the current moment, obtain the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike; wherein the remaining life of the arrester after the most recent lightning strike is obtained based on the lightning current flowing through the arrester during the most recent lightning strike; The quality of the arrester at the current moment is determined based on the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike.

[0005] In some embodiments of the present disclosure, the remaining life of the arrester after the most recent lightning strike is obtained according to the lightning current flowing through the arrester during the most recent lightning strike, and the formula is: ΔS=Sa×(∑+L); Wherein, ΔS is the remaining life of the arrester after the most recent lightning strike, S is the initial life of the arrester, a is the parameter that affects the life of the arrester due to the accumulated number of lightning strikes, ∑ is the accumulated number of lightning strikes before the most recent lightning strike, and L is the number of lightning strikes generated by the most recent lightning strike. The number of lightning strikes generated by a lightning strike is determined based on the lightning current and a preset mapping table, which defines the mapping relationship between the number of lightning strikes generated by a lightning strike and the lightning current.

[0006] In some embodiments of the present disclosure, the quality of the arrester at the current moment is determined according to the leakage current on the arrester at the current moment, the temperature of the arrester at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike, including: According to the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, the arrester temperature at the historical moment, and the ambient temperature of the arrester at the historical moment, a temperature curve is obtained; wherein the temperature at each moment in the temperature curve is the difference between the arrester temperature and the ambient temperature; If the remaining life is equal to 0 or a negative value, and the leakage current and / or temperature curve on the arrester at the current moment is abnormal, it is determined that there is a quality problem with the arrester at the current moment.

[0007] In some embodiments of the present disclosure, the abnormal condition of the temperature curve is: starting from any moment, the temperature in the temperature curve always exceeds the threshold.

[0008] According to another aspect of the present disclosure, there is provided a system for monitoring the quality of an operating lightning arrester, comprising: A data acquisition module, if the arrester is not struck by lightning at the current moment, acquires the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike; wherein the remaining life of the arrester after the most recent lightning strike is acquired based on the lightning current flowing through the arrester during the most recent lightning strike; The quality determination module determines the quality of the arrester at the current moment according to the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike.

[0009] According to another aspect of the present disclosure, there is provided a device for monitoring the quality of an operating arrester, comprising a separation acquisition device, a first temperature acquisition device, a second acquisition device and a terminal; Separate the collection device to collect the lightning current flowing through the lightning arrester when the lightning arrester is struck by lightning, and collect the leakage current on the lightning arrester when the lightning arrester is not struck by lightning; The first temperature collecting device and the second temperature collecting device collect the temperature of the arrester and the external environment temperature respectively; Terminal, the arrester quality monitoring method is used to monitor the arrester quality.

[0010] In some embodiments of the present disclosure, if the resistor sheet of the arrester is directly connected to the power distribution line, the separate collection device includes a discharge gap, a lightning current sensing device, a varistor RR1, a resistor RR2 and a current limiting circuit; One end of the discharge gap is connected to the end of the resistor away from the power distribution line, the other end of the discharge gap is grounded, and the lightning current sensing device senses the lightning current on the line between the discharge gap and the ground; One end of the varistor RR1 is grounded, the other end of the varistor RR1 is respectively connected to the disconnector and one end of the resistor RR2, and the other end of RR2 is connected to the ground with a current limiting circuit; wherein the resistor RR2 and the varistor RR1 constitute a leakage current sampling device to sample the leakage current on the arrester.

[0011] In some embodiments of the present disclosure, if the resistor of the arrester is connected to the distribution line through an insulator, The separate collection device includes a lightning current sensing device, a varistor RR1, a resistor RR2 and a current limiting circuit; One end of the varistor RR1 is connected to the resistor sheet and one end of the resistor RR2 respectively, the other end of the varistor RR1 is grounded, and the lightning current sensing device senses the lightning current on the discharge gap and the varistor RR1 line; A current limiting circuit is connected between the other end of RR2 and the ground; wherein the resistor RR2 and the varistor RR1 constitute a leakage current sampling device to sample the leakage current on the arrester.

[0012] In some embodiments of the present disclosure, the current limiting circuit includes a transformer, one end of the primary winding of the transformer is connected to the resistor RR2 through a first current limiting device, the other end of the primary winding of the transformer is grounded through a second current limiting device, and both ends of the secondary winding of the transformer are connected to a third current limiting device.

[0013] In some embodiments of the present disclosure, the first current limiting device and the second current limiting device have the same structure and include a plurality of parallel current limiting branches. The larger the current carrying capacity of the arrester, the greater the number of current limiting branches.

[0014] The beneficial effects achieved by the present invention are as follows: 1. The present invention collects lightning current, leakage current, arrester temperature and ambient temperature during lightning strike, uses lightning current to evaluate the remaining life of the arrester, and based on the remaining life, leakage current, arrester temperature and ambient temperature, realizes quality monitoring of the arrester in operation, which can ensure the healthy operation of the arrester and the safe and reliable operation of the distribution line, and has great economic value and social benefits; 2. The present invention abandons the traditional resistive current, introduces the arrester temperature and ambient temperature as monitoring parameters, and realizes the quality monitoring of the arrester without changing the safety properties of the arrester; 3. The present invention uses a separate collection device to collect lightning current and leakage current in a time-sharing manner, and the separate collection device has a built-in current limiting circuit, which can prevent the leakage current detection circuit from being impacted by a large current caused by a lightning strike. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Flow chart of the method for monitoring the quality of operating arresters; Figure 2 is the lightning current diagram per unit time; Figure 3 is the temperature curve diagram; Figure 4 To operate the block diagram of the arrester quality monitoring system; Figure 5 This is a schematic diagram of the first connection of separate collection devices; Figure 6 A first circuit diagram for separating the acquisition device; Figure 7 A second connection diagram for separate collection devices; Figure 8 A second circuit diagram for separating the acquisition device; Fig. 9 Schematic diagram of the current limiting circuit. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present disclosure to clearly and completely describe the technical solutions in the embodiments of the present disclosure. It is obvious that the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present disclosure and its application or use. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0017] Unless otherwise specified, the relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present disclosure.

[0018] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0019] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0020] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0021] It should be noted that similar symbols and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

[0022] In order to solve the problem of being unable to determine whether a lightning arrester in operation has deteriorated, the present disclosure proposes a method, system and device for monitoring the quality of a lightning arrester in operation. Specifically, the lightning current, leakage current, arrester temperature and ambient temperature during a lightning strike are collected, and the remaining life of the lightning arrester is evaluated using the lightning current. Based on the remaining life, leakage current, arrester temperature and ambient temperature, quality monitoring of the lightning arrester in operation is achieved, which can ensure the healthy operation of the lightning arrester and the safety of the distribution line.

[0023] Figure 1 It is a schematic diagram of an embodiment of the method for monitoring the quality of lightning arresters disclosed in the present invention. Figure 1 The embodiments may be executed by a remote monitoring terminal (such as a computer).

[0024] like Figure 1 As shown, in step 1 of the embodiment, if the lightning arrester is not struck by lightning at the current moment, obtain the leakage current on the lightning arrester at the current moment, the lightning arrester temperature at the current moment, the ambient temperature of the lightning arrester at the current moment, and the remaining life of the lightning arrester after the most recent lightning strike; wherein the remaining life of the lightning arrester after the most recent lightning strike is obtained based on the lightning current flowing through the lightning arrester during the most recent lightning strike.

[0025] It should be noted that the leakage current on the lightning arrester is the leakage current of the lightning arrester. Taking the common zinc oxide lightning arrester as an example, the leakage current is also considered to be the total leakage current of the lightning arrester.

[0026] Under normal rated power frequency voltage, the arrester can be regarded as an insulator. Taking into account the voltage fluctuation range, the indicator is set at a leakage of no more than 50μA at 0.75U1mA. In principle, the smaller the better. The leakage current can reflect the insulation condition of the arrester and is an important parameter for judging the quality of the arrester during operation.

[0027] The leakage current can be collected online by using an ED0403 zinc oxide lightning arrester characteristic tester. Of course, the structure of the present invention (see subsequent description for details) can also be used to periodically collect the leakage current during the period when the lightning arrester is not struck by lightning.

[0028] It should be noted that the resistive degradation of the arrester will cause the resistive current in the leakage current to change. Directly measuring the resistive current at the arrester requires the introduction of distribution network voltage measurement, that is, the resistive current in the leakage current can only be calculated through the voltage. However, it is unsafe to directly introduce the distribution network voltage line at the arrester, which may itself become a lightning strike path and endanger the safety of the distribution network. Therefore, the embodiment replaces the active property of the resistive current with temperature, specifically the arrester temperature and the ambient temperature. Both temperatures can be measured using common temperature sensors, or dual temperature measuring probes can be used to measure the two temperatures separately, such as one attached to the arrester resistor and the other directly exposed to the air around the arrester.

[0029] It should be noted that lightning current is the current that is discharged into the earth through the struck object when lightning strikes. Let's take the zinc oxide arrester as an example. The main component inside the arrester is the zinc oxide resistor. First, there is a potential barrier difference between the zinc oxide grains inside the zinc oxide resistor. Under the action of the external electric field, some zinc ions will migrate, causing the zinc oxide resistor to gradually lose its varistor characteristics. This is the inherent characteristic of the zinc oxide resistor. Its length is the natural life of the arrester. The lightning strike will accelerate its migration and evolution; secondly, the zinc oxide resistor is pressed from powder, and microcracks are inevitable inside. Lightning will flow along the microcracks along the easiest path, and each lightning strike will cause the microcracks to change. In other words, lightning strikes will affect the remaining life of the arrester, so lightning current is also an important parameter for judging the quality of the arrester during operation.

[0030] Generally speaking, the more times the lightning strikes, the shorter the remaining life of the lightning arrester, and the stronger the intensity of the lightning current, the shorter the remaining life of the lightning arrester. In order to intuitively understand the quality of the lightning arrester, the remaining life of the lightning arrester can be evaluated. In some embodiments, in order to facilitate the evaluation, the intensity of the lightning current can be converted into the number of lightning strikes. For example, a lightning current of 20% of the current carrying capacity corresponds to 1 lightning strike, 50% of the current carrying capacity corresponds to 5 lightning strikes, 100% of the current carrying capacity corresponds to 15 lightning strikes, and so on. Of course, this number is determined based on experience, so a mapping table can be pre-constructed, in which the mapping relationship between the number of lightning strikes and the lightning current generated by the lightning strike is defined.

[0031] Taking the most recent lightning strike at the current moment as an example, the formula for evaluating the remaining life of the arrester based on the number of lightning strikes can be as follows: ΔS=Sa×(∑+L); Where ΔS is the remaining life of the arrester after the most recent lightning strike, S is the initial life of the arrester, which is generally 15, a is the parameter that affects the life of the arrester due to the accumulated number of lightning strikes, which is generally 0.5, ∑ is the accumulated number of lightning strikes before the most recent lightning strike, and L is the number of lightning strikes caused by the most recent lightning strike.

[0032] It should be noted that the lightning current can be collected by using a common current transformer. When lightning strikes, the lightning current can be obtained by sensing the current on the grounding line of the lightning arrester through the current transformer.

[0033] In order to reveal the law of lightning activity, in some embodiments, the lightning current per unit time can be further calculated based on the lightning current, that is, the lightning current generated per unit time during the lightning strike. After the lightning current per unit time is calculated, Figure 2 It can be displayed to clearly know when and how strong the lightning arrester was struck by lightning. It can be used to reveal the laws of lightning activity and remind operation and maintenance personnel to pay attention to the safety of the lightning arrester under what lightning strike intensity.

[0034] return Figure 1 , step 2 of the embodiment, determines the quality of the arrester at the current moment according to the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike.

[0035] In some embodiments, the process of step 2 above may be as follows: 21) A temperature curve is obtained according to the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, the arrester temperature at the historical moment, and the ambient temperature of the arrester at the historical moment; wherein, in the temperature curve, the temperature at each moment is the difference between the arrester temperature and the ambient temperature.

[0036] It should be noted that the arrester temperature is actually a combination of two temperatures, namely the arrester temperature and the ambient temperature. In order to reduce the influence of the ambient temperature, the difference between the two temperatures at the same time can be calculated to construct a temperature curve. Figure 3 .

[0037] 22) If the remaining life is equal to 0 or a negative value, and the leakage current and / or internal temperature curve of the arrester are abnormal at the current moment, it is determined that there is a quality problem with the arrester at the current moment. It should be noted that for leakage current, it can be defined that if the leakage current deviates from the factory data by 20%~50%, it indicates a slight abnormality in leakage, reflecting that the arrester has deteriorated; if the leakage current deviates from the factory data by 50%~95%, it indicates a serious abnormality in leakage, reflecting that the arrester has seriously deteriorated; if the leakage current deviates from the factory data by 95%~100%, it indicates that the arrester is about to collapse.

[0038] It should be noted that if the quality of the lightning arrester is normal, then the temperature of the lightning arrester itself is generally normal. Figure 3 , the curve close to the 0-axis appears to be a straight line and changes slowly. When the temperature in the temperature curve always exceeds the threshold value (that is, the temperature is not on the 0-axis, the curve deviates significantly and cannot return to the vicinity of the 0-axis) from any moment, such as exceeding 5 degrees Celsius, the curve is judged to be abnormal; of course, the temperature deviation may also be the injection of lightning energy, but this is a short-term phenomenon and will return after a certain period of time.

[0039] The remaining life, leakage current and temperature curve are comprehensively considered as follows: If the remaining life is 0 or even a negative number, it is suggested that you need to consider replacing the arrester. However, the arrester is not necessarily bad at this time. Only when the leakage current is abnormal and / or the temperature curve is abnormal, it indicates that there is a problem with the quality of the arrester and you need to replace the arrester immediately.

[0040] The above method collects lightning current, leakage current, arrester temperature and ambient temperature during lightning strike, uses lightning current to evaluate the remaining life of the arrester, and based on the remaining life, leakage current, arrester temperature and ambient temperature, realizes quality monitoring of the arrester in operation, which can ensure the healthy operation of the arrester and the safe and reliable operation of the distribution line, and has great economic value and social benefits; and this method abandons the traditional resistive current and introduces the arrester temperature and ambient temperature as monitoring parameters, which can realize the quality monitoring of the arrester without changing the safety properties of the arrester.

[0041] Figure 4 A schematic diagram of an embodiment of a lightning arrester quality monitoring system disclosed in the present invention is shown in FIG. Figure 4 An embodiment of the present invention is a virtual device, such as software, which can be loaded and executed by a remote monitoring terminal (such as a computer), including a data acquisition module and a quality determination module.

[0042] The data acquisition module of the embodiment is configured to obtain, if the lightning arrester is not struck by lightning at the current moment, the leakage current on the lightning arrester, the temperature of the lightning arrester at the current moment, the ambient temperature of the lightning arrester at the current moment, and the remaining life of the lightning arrester after the most recent lightning strike; wherein the remaining life of the lightning arrester after the most recent lightning strike is obtained based on the lightning current flowing through the lightning arrester during the most recent lightning strike.

[0043] The quality determination module of the embodiment is configured to determine the quality of the arrester at the current moment based on the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike.

[0044] Similar to the above method, the system collects lightning current, leakage current, arrester temperature and ambient temperature during lightning strike, uses lightning current to evaluate the remaining life of the arrester, and based on the remaining life, leakage current, arrester temperature and ambient temperature, realizes quality monitoring of the arrester in operation, which can ensure the healthy operation of the arrester and the safe and reliable operation of the distribution line, and has great economic value and social benefits; and the system abandons the traditional resistive current and introduces the arrester temperature and ambient temperature as monitoring parameters, which can realize the quality monitoring of the arrester without changing the safety properties of the arrester.

[0045] In order to adapt to the above method, the present disclosure also discloses a hardware structure corresponding to the method, a device for monitoring the quality of an operating lightning arrester, including a separate collection device, a first temperature collection device, a second collection device and a terminal. The separate collection device collects the lightning current flowing through the lightning arrester when the lightning arrester is struck by lightning, and collects the leakage current on the lightning arrester when the lightning arrester is not struck by lightning; the first temperature collection device and the second temperature collection device collect the temperature of the lightning arrester and the ambient temperature respectively; the terminal uses the above-mentioned operating lightning arrester quality monitoring method to monitor the quality of the lightning arrester.

[0046] It should be noted that the first temperature acquisition device and the second temperature acquisition device are both temperature sensors. Dual temperature measuring probes can also be used to measure two temperatures respectively. The same type of temperature measuring heads, one is close to the zinc oxide part of the lightning arrester, and the other is exposed to the air near the lightning arrester.

[0047] It should be noted that there are currently two common structures of lightning arresters, one is that the resistor is connected to the distribution line through an insulator, and the other is that the resistor is directly connected to the distribution line.

[0048] See also Figure 5 , the insulator is connected to the distribution line, and the resistor is connected to the insulator. In order to adapt to the leakage current and lightning current collection of this structure, see Figure 6 The separate collection device includes a lightning current sensing device L1, a varistor RR1, a resistor RR2 and a current limiting circuit; one end of the varistor RR1 is respectively connected to the resistor and one end of the resistor RR2, and the other end of the varistor RR1 is grounded. The lightning current sensing device L1 senses the lightning current on the discharge gap and the varistor RR1 line, and a current transformer can be used specifically; the other end of RR2 is connected to the ground with a current limiting circuit; wherein the resistor RR2 and the varistor RR1 constitute a leakage current sampling device to sample the leakage current on the arrester.

[0049] When collecting leakage current, the resistance value of the varistor RR1 will not change. When the leakage current flows through the varistor RR1, a voltage drop will occur. At this time, the current signal is converted into a voltage signal and sent to the subsequent circuit through the resistor RR2. After the subsequent circuit is shaped, it is sent to the CPU for analog-to-digital conversion measurement. When the lightning current strikes, the voltage on the varistor RR1 will increase rapidly and exceed the varistor value, and the resistance value of the varistor RR1 will decrease to leak current.

[0050] The above circuit uses the same line to collect lightning current and leakage current in a time-sharing manner. In order to prevent the leakage current collection circuit from being impacted by large current from lightning strikes, a current limiting circuit is used to limit the current.

[0051] Although Figure 6 The structure can effectively realize the collection of lightning current and leakage current, but the two use the same line, it is difficult to avoid the influence of lightning current, so for further reference Figure 7 , the resistor is connected to the distribution line, the insulator is connected to the resistor, and the disconnector is connected to the insulator. In order to adapt to the leakage current and lightning current collection of this structure, refer to Figure 8 The separate collection device includes a discharge gap, a lightning current sensing device L1, a varistor RR1, a resistor RR2 and a current limiting circuit; one end of the discharge gap is connected to an end of the resistor away from the distribution line, and the other end of the discharge gap is grounded. The lightning current sensing device L1 senses the lightning current on the line between the discharge gap and the ground, and a current transformer can be used specifically; one end of the varistor RR1 is grounded, and the other end of the varistor RR1 is respectively connected to one end of the disconnector and the resistor RR2, and the other end of RR2 is connected to the current limiting circuit between the ground; wherein the resistor RR2 and the varistor RR1 constitute a leakage current sampling device to sample the leakage current on the arrester.

[0052] The lightning current is collected at the kA level, while the leakage current is collected at the uA level, which is 1 billion times different. In order to protect the leakage current collection, two collection lines are used here and the collection is performed in time sharing. The current limiting circuit is also used for current limiting. The lightning current collection has less impact on the leakage current collection, and the numerical accuracy of the collection is better than Figure 6 structure.

[0053] It should be noted that Figure 6 and Figure 8 The current limiting circuit in the circuit has the same structure, specifically including a transformer T1, one end of the primary winding of the transformer T1 is connected to the resistor RR2 through the first current limiting device, the other end of the primary winding of the transformer T1 is grounded through the second current limiting device, and both ends of the secondary winding of the transformer T1 are connected to the third current limiting device; wherein, the first current limiting device and the second current limiting device have the same structure, including a plurality of parallel current limiting branches, and the larger the current carrying capacity of the arrester, the greater the number of current limiting branches. A two-stage current limiting method is used here to further ensure the current limiting effect.

[0054] For the specific structure of the current limiting circuit, please refer to Fig. 9, taking a current limiting branch as an example, the diode D1 and the diode D2 connected with the positive poles constitute the current limiting branch, one end of the primary winding of the transformer T1 is connected to the resistor RR2 through the current limiting branch, and the other end is grounded through the current limiting branch of the same structure, the third current limiting device includes a diode D3, a diode D4, a diode D5, a diode D6, a diode D7, a diode D8, a diode D9, a resistor R1 and a resistor R2, and the two ends of the secondary winding of the transformer T1 are respectively connected to the positive pole of the diode D4 and the positive pole of the diode D5, The cathode of diode D3 is connected to the anode of diode D4, the anode of diode D3 is grounded, the cathode of diode D6 is connected to the anode of diode D5, the anode of diode D6 is grounded, the cathode of diode D4 is respectively connected to the cathode of diode D5 and the anode of diode D7, the cathode of diode D7 is respectively connected to the cathode of diode D9, the anode of diode D8 and one end of resistor R1, the cathode of diode D8 is connected to a 3.3V power supply, the anode of diode D9 is grounded, and the other end of resistor R1 is grounded through resistor R2.

[0055] On the primary winding side of transformer T1, the diodes of the current limiting branch form a current limiting array to achieve front-end current limiting. When lightning strikes, the current limiting array will quickly exhaust the carriers to prevent the sudden rise of lightning voltage. However, there will still be a small spike pulse voltage on the secondary side of transformer T1. The subsequent current limiting circuit will consume this energy, and the varistor RR1 will simultaneously become less resistant to discharge current, which can effectively protect the circuit from being struck by lightning and high current. When there is no lightning strike, the varistor restores its original resistance, and the current limiting array also restores the carriers, so that normal leakage current detection can be performed.

[0056] It should be noted that the terminal can be a computer or a mobile phone. The data collected on the arrester side will be periodically sent to the terminal, which can display the collected data, the data calculated during the quality monitoring process (such as the number of lightning strikes, etc.), and the monitoring results, and give certain prompts in the event of anomalies or failures, such as alarms, red displays, etc.

[0057] The above-mentioned device creatively changes the leakage current monitoring circuit that is easily damaged by lightning strikes, and introduces other parameters that characterize lightning and resistive degradation for the first time. Without changing the safety properties of the lightning arrester, it can remotely monitor the parameters of the operating lightning arrester in real time and judge the quality of the lightning arrester. This allows maintenance personnel to perform fast, accurate and targeted maintenance, ensure the healthy operation of the line lightning arrester, and ensure the safe and reliable operation of the distribution network lines. It has great economic value and social benefits.

[0058] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0059] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0060] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0061] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0062] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A method for monitoring the quality of a lightning arrester in operation, characterized in that: include: If the arrester is not struck by lightning at the current moment, obtain the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike; wherein the remaining life of the arrester after the most recent lightning strike is obtained based on the lightning current flowing through the arrester during the most recent lightning strike; The quality of the arrester at the current moment is determined based on the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike.

2. The method according to claim 1, characterized in that The remaining life of the arrester after the most recent lightning strike is obtained based on the lightning current flowing through the arrester during the most recent lightning strike. The formula is: ΔS=Sa×(∑+L); Wherein, ΔS is the remaining life of the arrester after the most recent lightning strike, S is the initial life of the arrester, a is the parameter that affects the life of the arrester due to the accumulated number of lightning strikes, ∑ is the accumulated number of lightning strikes before the most recent lightning strike, and L is the number of lightning strikes generated by the most recent lightning strike. The number of lightning strikes generated by a lightning strike is determined based on the lightning current and a preset mapping table, which defines the mapping relationship between the number of lightning strikes generated by a lightning strike and the lightning current.

3. The method according to claim 1, characterized in that Determine the quality of the arrester at the current moment based on the current arrester leakage current, the current arrester temperature, the current arrester ambient temperature, and the remaining life of the arrester after the most recent lightning strike, including: According to the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, the arrester temperature at the historical moment, and the ambient temperature of the arrester at the historical moment, a temperature curve is obtained; wherein the temperature at each moment in the temperature curve is the difference between the arrester temperature and the ambient temperature; If the remaining life is equal to 0 or a negative value, and the leakage current and / or temperature curve on the arrester at the current moment is abnormal, it is determined that there is a quality problem with the arrester at the current moment.

4. The method according to claim 3, characterized in that The abnormal condition of the temperature curve is: starting from any moment, the temperature in the temperature curve always exceeds the threshold.

5. A system for monitoring the quality of operating lightning arresters, characterized in that: include: A data acquisition module, if the arrester is not struck by lightning at the current moment, acquires the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike; wherein the remaining life of the arrester after the most recent lightning strike is acquired based on the lightning current flowing through the arrester during the most recent lightning strike; The quality determination module determines the quality of the arrester at the current moment according to the leakage current on the arrester at the current moment, the arrester temperature at the current moment, the ambient temperature of the arrester at the current moment, and the remaining life of the arrester after the most recent lightning strike.

6. A device for monitoring the quality of an operating lightning arrester, characterized in that: It includes a separation collection device, a first temperature collection device, a second collection device and a terminal; Separate the collection device to collect the lightning current flowing through the lightning arrester when the lightning arrester is struck by lightning, and collect the leakage current on the lightning arrester when the lightning arrester is not struck by lightning; The first temperature collecting device and the second temperature collecting device collect the temperature of the arrester and the ambient temperature respectively; The terminal uses the method described in any one of claims 1 to 4 to monitor the quality of the lightning arrester.

7. The device according to claim 6, characterized in that If the arrester resistor is directly connected to the distribution line, the separate collection device includes a discharge gap, a lightning current sensing device, a varistor RR1, a resistor RR2 and a current limiting circuit; One end of the discharge gap is connected to the end of the resistor away from the power distribution line, the other end of the discharge gap is grounded, and the lightning current sensing device senses the lightning current on the line between the discharge gap and the ground; One end of the varistor RR1 is grounded, the other end of the varistor RR1 is respectively connected to the disconnector and one end of the resistor RR2, and the other end of RR2 is connected to the ground with a current limiting circuit; wherein the resistor RR2 and the varistor RR1 constitute a leakage current sampling device to sample the leakage current on the arrester.

8. The device according to claim 6, characterized in that If the arrester resistor is connected to the distribution line through an insulator, The separate collection device includes a lightning current sensing device, a varistor RR1, a resistor RR2 and a current limiting circuit; One end of the varistor RR1 is connected to the resistor sheet and one end of the resistor RR2 respectively, the other end of the varistor RR1 is grounded, and the lightning current sensing device senses the lightning current on the discharge gap and the varistor RR1 line; A current limiting circuit is connected between the other end of RR2 and the ground; wherein the resistor RR2 and the varistor RR1 constitute a leakage current sampling device to sample the leakage current on the arrester.

9. The device according to claim 7 or 8, characterized in that The current limiting circuit includes a transformer, one end of the primary winding of the transformer is connected to the resistor RR2 through a first current limiting device, the other end of the primary winding of the transformer is grounded through a second current limiting device, and both ends of the secondary winding of the transformer are connected to a third current limiting device.

10. The device according to claim 9, characterized in that The first current limiting device and the second current limiting device have the same structure and include a plurality of parallel current limiting branches. The larger the current carrying capacity of the arrester is, the greater the number of current limiting branches is.

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