Lightning arrester resistor disc impact characteristic detection system and method under multiple lightning strokes

Abstract

The invention discloses a lightning arrester resistor disc impact characteristic detection system under multiple lightning strokes. The lightning arrester resistor disc impact characteristic detection system comprises a pulse current discharge device and an impact characteristic analyzer, the pulse current discharge device is connected in series with a to-be-tested lightning arrester resistor disc through an electric lead to form a loop, simulates active discharge of lightning current under multiple lightning strokes and subsequent n times of return strokes under a discharge working condition, and loads the active discharge and the subsequent n times of return strokes on the to-be-tested lightning arrester resistor disc in sequence according to n discharge time intervals; the impact characteristic analyzer is connected with an electric lead through a current transformer to acquire current in real time, and identifies impact current waves when lightning current is loaded on the to-be-tested lightning arrester resistor disc, so as to determine the impact characteristics of the to-be-tested lightning arrester resistor disc, including the maximum impact bearing frequency. The current peak value of each impact current wave from the first impact time to the maximum impact bearing time and the time interval between every two adjacent impact current waves are obtained. According to the invention, the impact characteristics of the resistor disc of the lightning arrester under the condition of multiple lightning strokes are analyzed, and the fault reason of the lightning arrester is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of computer simulation, and in particular to a system and method for detecting impulse characteristics of arrester resistors under multiple lightning strikes. Background Art

[0002] The south is a thunderstorm-prone area, so there are often multiple lightning strikes when thunderclouds discharge to the ground. When the first charge center completes the above discharge process, there may be a second, third or even multiple charge centers that start a new discharge process along the original discharge channel, which is a subsequent return stroke (also known as secondary return stroke, tertiary return stroke, etc.). In particular, there is no mandatory requirement to install lightning arresters at the line entrance in 220kV and below substations. After the first lightning strike causes the circuit breaker to trip, the line side of the circuit breaker break will lose the protection of the lightning arrester. If it is struck by lightning again, it may cause damage to the line side equipment, seriously threatening the safe operation of key equipment such as circuit breakers.

[0003] Therefore, China Southern Power Grid Company proposed anti-accident measures: lightning arresters should be installed on the line side of normal hot standby lines in substations and areas with frequent lightning activities. At present, some scholars have analyzed the ability of lightning arresters to withstand lightning impulse current based on the impulse characteristics of lightning arrester resistors, but this method is limited to single lightning strikes.

[0004] However, there have been many incidents and problems of equipment failures caused by multiple continuous lightning strikes in substations. Therefore, it is necessary to analyze the impact characteristics of arrester resistors under multiple lightning strikes, which is of great significance for analyzing the causes of arrester failures and formulating countermeasures. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a system and method for detecting the impulse characteristics of arrester resistors under multiple lightning strikes, which can analyze the impulse characteristics of arrester resistors under multiple lightning strikes, and is conducive to further studying the causes of arrester failures.

[0006] In order to solve the above technical problems, an embodiment of the present invention provides a lightning arrester resistor impulse characteristic detection system under multiple lightning strikes, including a pulse current discharge device and an impulse characteristic analyzer; wherein,

[0007] The pulse current discharge device is connected in series with the resistor of the arrester to be tested through an electric conductor to form a loop, and is used to simulate the active discharge of lightning current under multiple lightning strikes and its subsequent n return strikes under the discharge condition, and sequentially load the simulated n+1 lightning currents on the resistor of the arrester to be tested according to the discharge time intervals between n preset adjacent lightning currents; n is a positive integer greater than or equal to 1;

[0008] The impulse characteristic analyzer is connected to the electric conductor through a current transformer, and is used to obtain the current collected by the current transformer on the electric conductor in real time, so as to further identify the impulse current waves corresponding to the simulated n+1 lightning currents when they are respectively loaded on the resistor of the lightning arrester to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, the impulse characteristic of the lightning arrester resistor to be tested is determined; wherein, the impulse characteristic includes the maximum number of impulses to be borne, the current peak value of each impulse current wave from the first to the maximum number of impulses to be borne, and the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne; the current peak value of the first impulse current wave is the same as the current peak value of the active discharge of the lightning current, and the current peak values ​​of other impulse currents except the first one are sequentially the same as the current peak value of each lightning current return stroke discharge; the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne forms a mapping relationship with the discharge time interval between adjacent lightning currents.

[0009] Wherein, the pulse current discharge device is composed of a main discharge branch and n return branches, and the main discharge branch and each return branch are connected in parallel; wherein,

[0010] The main discharge branch and the n return stroke branches all include chargeable and dischargeable capacitors and discharge spherical gaps; each capacitor is used to store the discharge voltage of the discharge branch and discharge under discharge conditions to simulate the release of lightning current; each discharge spherical gap is used to set the discharge time interval of the lightning current between the discharge branch and its next adjacent discharge branch.

[0011] In which, the pulse current discharge device is also connected to the AC power supply through a preset DC charging unit, and is used to provide AC power from the AC power supply and convert it into DC power through the DC charging unit under charging conditions to charge the capacitors on each discharge branch until the voltage of the capacitors on each discharge branch reaches their respective discharge voltages.

[0012] The discharge voltage is calculated based on the peak current of the lightning current expected to be released on each discharge branch and combined with the corresponding discharge circuit parameters.

[0013] Among them, the impact characteristic analyzer is connected to the arrester resistor to be tested through a temperature sensor, and is also used to obtain the temperature on the arrester resistor to be tested collected by the temperature sensor in real time, so as to further identify the corresponding withstand temperature when the impact current is from the first to the maximum number of impacts, and further select the maximum value from the identified multiple withstand temperatures as the maximum temperature of the arrester resistor to be tested.

[0014] The embodiment of the present invention further provides a method for detecting the impulse characteristics of a lightning arrester resistor under multiple lightning strikes, which is implemented on the aforementioned lightning arrester resistor impulse characteristics detection system under multiple lightning strikes. The method comprises the following steps:

[0015] The pulse current discharge device simulates the active discharge of lightning current under multiple lightning strikes and its subsequent n return strikes under the discharge condition, and sequentially loads the simulated n+1 lightning currents on the resistor of the arrester to be tested according to the discharge time intervals between n preset adjacent lightning currents; n is a positive integer greater than or equal to 1;

[0016] The impulse characteristic analyzer obtains the current collected by the current transformer in real time to further identify the impulse current waves corresponding to the simulated n+1 lightning currents when they are respectively loaded on the arrester resistor to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, the impulse characteristic of the arrester resistor to be tested is determined; wherein, the impulse characteristic includes the maximum number of impulses to be borne, the current peak value of each impulse current wave from the first to the maximum number of impulses to be borne, and the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne; the current peak value of the first impulse current wave is the same as the current peak value of the active discharge of the lightning current, and the current peak value of other impulse currents except the first one is sequentially the same as the current peak value of each lightning current return discharge; the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne forms a mapping relationship with the discharge time interval between adjacent lightning currents.

[0017] Wherein, the method further comprises:

[0018] The pulse current discharge device obtains the temperature on the resistor of the lightning arrester to be tested, which is collected in real time by the temperature sensor, so as to further identify the corresponding withstand temperature when the impact current is subjected to the impact times from the first time to the maximum time, and further selects the maximum value from the identified multiple withstand temperatures as the maximum temperature of the resistor of the lightning arrester to be tested.

[0019] Wherein, the method further comprises:

[0020] In the charging condition, the pulse current discharge device is provided with AC power by the AC power supply and converted into DC power by the DC charging unit to charge the capacitors on each discharge branch until the voltage of the capacitors on each discharge branch reaches the respective discharge voltage.

[0021] The discharge voltage is calculated based on the peak current of the lightning current expected to be released on each discharge branch and combined with the corresponding discharge circuit parameters.

[0022] The implementation of the embodiments of the present invention has the following beneficial effects:

[0023] The present invention simulates active discharge of lightning current under multiple lightning strikes and subsequent n return strikes by means of a pulse current discharge device under discharge conditions, and sequentially loads the simulated n+1 lightning currents on the arrester resistor to be tested according to the discharge time intervals between n preset adjacent lightning currents, further utilizes an impulse characteristic analyzer to obtain the current collected in real time by a current transformer, identifies the impulse current wave loaded on the arrester resistor to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, determines the impulse characteristic of the arrester resistor to be tested, thereby realizing analysis of the impulse characteristic of the arrester resistor under multiple lightning strikes, which is beneficial to further study the cause of the arrester failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still belong to the scope of the present invention.

[0025] Figure 1 A schematic diagram of the structure of a system for detecting impulse characteristics of arrester resistors under multiple lightning strikes provided by an embodiment of the present invention;

[0026] Figure 2 A circuit connection diagram of a pulse current discharge device in a lightning arrester resistor impulse characteristic detection system under multiple lightning strikes provided by an embodiment of the present invention;

[0027] Figure 3 A flow chart of a method for detecting impulse characteristics of arrester resistors under multiple lightning strikes provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] like Figure 1 As shown, in an embodiment of the present invention, a lightning arrester resistor impulse characteristic detection system under multiple lightning strikes is proposed, comprising a pulse current discharge device 1 and an impulse characteristic analyzer 2; wherein,

[0030] The pulse current discharge device 1 is connected in series with the arrester resistor T to be tested through the electric conductor L to form a loop, and is used to simulate the active discharge of lightning current under multiple lightning strikes and its subsequent n return strikes under the discharge condition, and sequentially load the simulated n+1 lightning currents on the arrester resistor T to be tested according to the discharge time interval between n preset adjacent lightning currents; n is a positive integer greater than or equal to 1;

[0031] The impulse characteristic analyzer 2 is connected to the electric conductor L through the current transformer CT, and is used to obtain the current collected by the current transformer CT on the electric conductor L in real time, so as to further identify the impulse current waves corresponding to the simulated n+1 lightning currents when they are respectively loaded on the arrester resistor T to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, the impulse characteristic of the arrester resistor T to be tested is determined; wherein the impulse characteristic includes the maximum number of impulses to be borne, the current peak value of each impulse current wave from the first to the maximum number of impulses to be borne, and the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne; the current peak value of the first impulse current wave is the same as the current peak value of the active discharge of the lightning current, and the current peak value of other impulse currents except the first one is sequentially the same as the current peak value of each lightning current return stroke discharge; the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne forms a mapping relationship with the discharge time interval between adjacent lightning currents (for example, a one-to-one correspondence and equal relationship).

[0032] It should be noted that the lightning impulse limit condition can be designed as the amplitude of the impulse current wave drops to a certain threshold or other. At this time, if the impulse current wave does not meet the lightning impulse limit condition, the impulse characteristics of the arrester resistor T to be tested can also be determined, but the maximum number of impulses and its corresponding impulse current wave are not included.

[0033] It is understandable that the impulse characteristic analyzer 1 can also be connected to the arrester resistor T to be tested through the temperature sensor S, and is also used to obtain the temperature of the arrester resistor T to be tested collected by the temperature sensor S in real time, so as to further identify the corresponding withstand temperature when the impulse current is from the first to the maximum withstand impulse times, and further select the maximum value from the identified multiple withstand temperatures as the maximum temperature of the arrester resistor T to be tested. Of course, if the impulse current wave does not meet the lightning impulse limit condition, the maximum temperature of the arrester resistor T to be tested can also be determined.

[0034] In the embodiment of the present invention, Figure 2As shown, the pulse current discharge device 1 is composed of a main discharge branch and n return stroke branches, and the main discharge branch is connected in parallel with each return stroke branch; wherein the main discharge branch and the n return stroke branches include chargeable and dischargeable capacitors and discharge spherical gaps; each capacitor is used to store the discharge voltage of the discharge branch, and discharges under discharge conditions to simulate the release of lightning current; each discharge spherical gap is used to set the discharge time interval of the lightning current between the discharge branch and its next adjacent discharge branch. Among them, the discharge voltage is calculated based on the current peak value of the lightning current expected to be released on each discharge branch, combined with the corresponding discharge circuit parameters. In an example, taking the discharge circuit parameters as loop impedance 2Ω and main discharge current peak 32.5kA as an example, the discharge voltage of the main discharge branch is 65kV.

[0035] In the embodiment of the present invention, the pulse current discharge device 1 is also connected to an AC power source (not shown) through a preset DC charging unit (not shown), and is used to charge the capacitors on each discharge branch by providing AC power from the AC power source and converting it into DC power through the DC charging unit under charging conditions, until the voltage of the capacitors on each discharge branch reaches the respective discharge voltage. It should be noted that charging a storage container with a DC power storage function through an AC power source through a sorting unit or a DC charging unit is a conventional technical means in the art, which will not be described in detail here.

[0036] In one embodiment, the arrester resistor impulse characteristic detection system is mainly composed of a high voltage power supply (ie, an AC power supply), a DC charging unit, a pulse current discharge device, a test piece (ie, the arrester resistor to be tested), and an impulse characteristic analyzer.

[0037] First, the discharge voltage of multiple discharge branches is selected on the pulse current discharge device. At this time, the alternating current provided by the high voltage power supply is rectified by the DC charging unit and then charged in parallel to the capacitors of each branch in the pulse current discharge device until the discharge voltage of each branch is reached.

[0038] Secondly, set the number of discharges (i.e. the value of n+1), the time interval between group discharges, and the peak current of the lightning current expected to be released by each branch, and set the scale factor of the measuring sensor (such as current transformer, temperature sensor);

[0039] Taking the actual six-fold lightning strike as an example, the time intervals for discharges of each branch are shown in Table 1 below.

[0040] Table 1

[0041]

[0042]

[0043] Then, the impulse characteristic analyzer collects the current flowing through the test product and the temperature of the test product through the current transformer and temperature sensor, and selects the data analysis and processing of the arrester impulse current test special software.

[0044] Finally, after the pulse current discharge device is charged, the main discharge branch, the first return stroke branch, the second return stroke branch, ..., the nth return stroke branch are used to discharge in sequence according to the above-set time intervals and load on the test product. The test can generate impact current waves such as 8 / 20μs, 4 / 10μs, 5 / 50μs, 10 / 50μs, etc., and the impact characteristics are analyzed by the impact characteristics analyzer.

[0045] In order to simulate the effect of multi-pulse discharge on the performance degradation of the arrester during the actual lightning strike, the inventor designed a lightning strike test with the same number of lightning strike pulses, different time intervals and different lightning current peak values. At this time, the number of lightning currents is selected as quadruple waves, the time interval between pulses is designed to be 50ms, and the time intervals of different test pieces (i.e., the arrester resistor to be tested) are designed to be 10min and 2min, as shown in Table 2. After a certain number of groups or a certain number of impacts, the test piece is placed at room temperature, the small current volt-ampere characteristics of the test piece are measured, and then the impact test is continued, and the above steps are repeated until the test piece is damaged.

[0046] Table 2

[0047] Sample No. Current peak / kA Test time interval / min Maximum temperature of test sample / ℃ Maximum number of impacts DLI-S1 40 10 103.2 323 DLI-S2 40 2 210 996 DLI-S3 50 2 229.2 210

[0048] like Figure 3 As shown, a method for detecting the impulse characteristics of a lightning arrester resistor under multiple lightning strikes is provided in an embodiment of the present invention. The method is implemented on a system for detecting the impulse characteristics of a lightning arrester resistor under multiple lightning strikes in an embodiment of the present invention. The method comprises the following steps:

[0049] Step S1, the pulse current discharge device simulates the active discharge of lightning current under multiple lightning strikes and its subsequent n return strikes under the discharge condition, and sequentially loads the simulated n+1 lightning currents on the resistor of the arrester to be tested according to the discharge time intervals between n preset adjacent lightning currents; n is a positive integer greater than or equal to 1;

[0050] Step S2, the impulse characteristic analyzer obtains the current collected by the current transformer in real time to further identify the impulse current waves corresponding to the simulated n+1 lightning currents when they are respectively loaded on the arrester resistor to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, the impulse characteristics of the arrester resistor to be tested are determined; wherein the impulse characteristics include the maximum number of impulses to be borne, the current peak value of each impulse current wave from the first to the maximum number of impulses to be borne, and the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne; the current peak value of the first impulse current wave is the same as the current peak value of the active discharge of the lightning current, and the current peak value of other impulse currents except the first one is sequentially the same as the current peak value of each lightning current return discharge; the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne forms a mapping relationship with the discharge time interval between adjacent lightning currents.

[0051] Wherein, the method further comprises:

[0052] The pulse current discharge device obtains the temperature on the resistor of the lightning arrester to be tested, which is collected in real time by the temperature sensor, so as to further identify the corresponding withstand temperature when the impact current is subjected to the impact times from the first time to the maximum time, and further selects the maximum value from the identified multiple withstand temperatures as the maximum temperature of the resistor of the lightning arrester to be tested.

[0053] Wherein, the method further comprises:

[0054] In the charging condition, the pulse current discharge device is provided with AC power by the AC power supply and converted into DC power by the DC charging unit to charge the capacitors on each discharge branch until the voltage of the capacitors on each discharge branch reaches the respective discharge voltage.

[0055] The discharge voltage is calculated based on the peak current of the lightning current expected to be released on each discharge branch and combined with the corresponding discharge circuit parameters.

[0056] The implementation of the embodiments of the present invention has the following beneficial effects:

[0057] The present invention simulates active discharge of lightning current under multiple lightning strikes and subsequent n return strikes by means of a pulse current discharge device under discharge conditions, and sequentially loads the simulated n+1 lightning currents on the arrester resistor to be tested according to the discharge time intervals between n preset adjacent lightning currents, further utilizes an impulse characteristic analyzer to obtain the current collected in real time by a current transformer, identifies the impulse current wave loaded on the arrester resistor to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, determines the impulse characteristic of the arrester resistor to be tested, thereby realizing analysis of the impulse characteristic of the arrester resistor under multiple lightning strikes, which is beneficial to further study the cause of the arrester failure.

[0058] A person skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, such as ROM / RAM, disk, CD-ROM, etc.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A lightning arrester resistor impulse characteristic detection system under multiple lightning strikes, characterized in that: It includes a pulse current discharge device and an impact characteristic analyzer; wherein, The pulse current discharge device is connected in series with the resistor of the arrester to be tested through an electric conductor to form a loop, and is used to simulate the active discharge of lightning current under multiple lightning strikes and its subsequent n return strikes under the discharge condition, and sequentially load the simulated n+1 lightning currents on the resistor of the arrester to be tested according to the discharge time intervals between n preset adjacent lightning currents; n is a positive integer greater than or equal to 1; The impulse characteristic analyzer is connected to the electric conductor through a current transformer, and is used to obtain the current collected by the current transformer on the electric conductor in real time, so as to further identify the impulse current waves corresponding to the simulated n+1 lightning currents when they are respectively loaded on the resistor of the lightning arrester to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, the impulse characteristic of the lightning arrester resistor to be tested is determined; wherein, the impulse characteristic includes the maximum number of impulses to be borne, the current peak value of each impulse current wave from the first to the maximum number of impulses to be borne, and the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne; the current peak value of the first impulse current wave is the same as the current peak value of the active discharge of the lightning current, and the current peak values ​​of other impulse currents except the first one are sequentially the same as the current peak value of each lightning current return stroke discharge; the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne forms a mapping relationship with the discharge time interval between adjacent lightning currents.

2. The arrester resistor impulse characteristic detection system under multiple lightning strikes as claimed in claim 1, characterized in that: The pulse current discharge device is composed of a main discharge branch and n return branches, and the main discharge branch and each return branch are connected in parallel; wherein, The main discharge branch and the n return stroke branches all include chargeable and dischargeable capacitors and discharge spherical gaps; each capacitor is used to store the discharge voltage of the discharge branch and discharge under discharge conditions to simulate the release of lightning current; each discharge spherical gap is used to set the discharge time interval of the lightning current between the discharge branch and its next adjacent discharge branch.

3. The arrester resistor impulse characteristic detection system under multiple lightning strikes as claimed in claim 2, characterized in that: The pulse current discharge device is also connected to an AC power source through a preset DC charging unit, and is used to, under charging conditions, provide AC power from the AC power source and convert it into DC power through the DC charging unit to charge the capacitors on each discharge branch until the voltage of the capacitors on each discharge branch reaches their respective discharge voltages.

4. The arrester resistor impulse characteristic detection system under multiple lightning strikes as claimed in claim 3, characterized in that: The discharge voltage is calculated based on the current peak value of the lightning current expected to be released on each discharge branch and combined with the corresponding discharge circuit parameters.

5. The arrester resistor impulse characteristic detection system under multiple lightning strikes as described in claim 4, characterized in that: The impact characteristic analyzer is connected to the arrester resistor to be tested via a temperature sensor, and is also used to obtain the temperature on the arrester resistor to be tested collected by the temperature sensor in real time, so as to further identify the corresponding withstand temperature when the impact current is from the first to the maximum number of impacts, and further select the maximum value from the identified multiple withstand temperatures as the maximum temperature of the arrester resistor to be tested.

6. A method for detecting the impulse characteristics of arrester resistors under multiple lightning strikes, characterized in that: The method is implemented on the arrester resistor impulse characteristic detection system under multiple lightning strikes as described in claim 5, and the method comprises the following steps: The pulse current discharge device simulates the active discharge of lightning current under multiple lightning strikes and its subsequent n return strikes under the discharge condition, and sequentially loads the simulated n+1 lightning currents on the resistor of the arrester to be tested according to the discharge time intervals between n preset adjacent lightning currents; n is a positive integer greater than or equal to 1; The impulse characteristic analyzer obtains the current collected by the current transformer in real time to further identify the impulse current waves corresponding to the simulated n+1 lightning currents when they are respectively loaded on the arrester resistor to be tested, and when it is determined that a certain impulse current wave meets the preset lightning impulse limit condition, the impulse characteristic of the arrester resistor to be tested is determined; wherein, the impulse characteristic includes the maximum number of impulses to be borne, the current peak value of each impulse current wave from the first to the maximum number of impulses to be borne, and the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne; the current peak value of the first impulse current wave is the same as the current peak value of the active discharge of the lightning current, and the current peak value of other impulse currents except the first one is sequentially the same as the current peak value of each lightning current return discharge; the time interval between two adjacent impulse currents from the first to the maximum number of impulses to be borne forms a mapping relationship with the discharge time interval between adjacent lightning currents.

7. The method for detecting the impulse characteristics of arrester resistors under multiple lightning strikes as claimed in claim 6, characterized in that: The method further comprises: The pulse current discharge device obtains the temperature on the resistor of the lightning arrester to be tested, which is collected in real time by the temperature sensor, so as to further identify the corresponding withstand temperature when the impact current is subjected to the impact times from the first time to the maximum time, and further selects the maximum value from the identified multiple withstand temperatures as the maximum temperature of the resistor of the lightning arrester to be tested.

8. The method for detecting the impulse characteristics of arrester resistors under multiple lightning strikes as claimed in claim 7, characterized in that: The method further comprises: In the charging condition, the pulse current discharge device is provided with AC power by the AC power supply and converted into DC power by the DC charging unit to charge the capacitors on each discharge branch until the voltage of the capacitors on each discharge branch reaches the respective discharge voltage.

9. The method for detecting the impulse characteristics of arrester resistors under multiple lightning strikes as claimed in claim 8, characterized in that: The discharge voltage is calculated based on the current peak value of the lightning current expected to be released on each discharge branch and combined with the corresponding discharge circuit parameters.

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