Forest standing tree lightning shunting characteristic test system and lightning shunting characteristic test and analysis method

Abstract

The invention discloses a forest stumpage lightning shunting characteristic test system and a lightning shunting characteristic test and analysis method, and the system comprises a lightning pulse current source, a forest stumpage, a clamping mechanism, and a lightning current control and electrical parameter measurement and analysis unit. According to natural structure characteristics of the forest stumpage, partition characteristics of the forest stumpage and correlation between distribution characteristics of lightning current in different partitions and factors such as moisture content, temperature and humidity of a forest stumpage sample are finally obtained by applying a data statistical method through distribution test data of partition areas of the forest stumpage under the action of the lightning current. A forest standing tree lightning shunting characteristic database simulating forest lightning fire characteristics of different regional characteristics is formed, and a foundation is laid for multi-physics field modeling of forest combustible lightning stroke and research of a lightning fire mechanism and a prediction algorithm.

Description

Technical Field

[0001] The invention relates to a forest lightning fire characteristic test technology, and in particular to a forest standing tree lightning shunt characteristic test system and a lightning shunt characteristic test and analysis method. Background Art

[0002] With global warming and the increase in extreme weather, lightning activities are frequent and the frequency of lightning fires has increased significantly, which not only seriously damages forest resources and the ecological environment, but also poses great harm to people's lives, property and public safety, and poses a huge threat to the sustainable development of the national economy and ecological security. In the past 10 years, the proportion of lightning fires in major forest fires in my country has increased from 5% to more than 60%. The cause mechanism of lightning fires is complex, and it is difficult to monitor and detect, and difficult to extinguish and deal with. The monitoring, early warning and prevention and control of lightning fires have become a global problem.

[0003] Lightning is a multiple continuous time-series discharge process. In the process of multiple lightning strikes, the first lightning component plays a vital role, involving the attachment process of lightning strikes to forest vegetation, forest standing trees and other combustibles, which directly affects the lightning shunting characteristics of lightning current in vegetation, forest standing trees, humus layers and other combustibles, and is of great significance for the theoretical study of forest lightning smoldering or ignition mechanisms. Existing research on lightning fires is mainly based on the establishment of prediction models based on historical lightning fire data, and the probability and area of ​​lightning fires are predicted according to meteorological conditions and forest conditions. There are very few research literature reports on the generation and development of lightning fires based on the physical process or mechanism of lightning attachment to forest combustibles and lightning shunting. Therefore, it is difficult to guarantee the accuracy of existing prediction models for lightning warnings. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a forest standing tree lightning shunt characteristic test system and a lightning shunt characteristic test and analysis method, so as to provide dynamic electrical characteristic laws for multi-physics field modeling and calculation of smoldering and ignition mechanisms caused by lightning strikes on forest standing trees.

[0005] The present invention is achieved through the following technical solutions:

[0006] A forest standing tree lightning shunt characteristic test system, comprising a lightning pulse current source, forest standing trees, a clamping mechanism, a lightning current control and an electrical parameter measurement and analysis unit;

[0007] The lightning pulse current source is used to generate lightning pulse current, including a controllable high-voltage DC charging power supply and a lightning pulse current generating unit. The controllable high-voltage DC charging power supply monitors the charging voltage of the lightning pulse current generating unit online through a charging voltage monitoring sensor, and transmits the charging voltage analog quantity to the control unit of the lightning current control and its electrical parameter measurement and analysis unit;

[0008] The forest standing trees are installed through a clamping mechanism and are electrically connected to the lightning pulse current generating unit;

[0009] The clamping mechanism is a mounting fixture having a high-voltage electrode HV and a plurality of low-voltage electrodes LV, the high-voltage electrode HV is a circular electrode having a size consistent with the end face of a forest tree, the plurality of low-voltage electrodes are circular or annular electrodes corresponding to the texture of the other end face of the forest tree, the high-voltage electrode HV is electrically connected to the output high-voltage port of the lightning pulse current generating unit, and the plurality of low-voltage electrodes are electrically connected to the low-voltage ports of the lightning pulse current generating unit respectively;

[0010] The lightning current control and electrical parameter measurement and analysis unit are used to realize the control of the forest standing tree lightning current shunting test and the measurement and analysis of the electrical parameters of the lightning pulse current, and include a control unit and a lightning pulse current measurement and analysis unit.

[0011] Furthermore, the controllable high-voltage DC charging power supply is composed of an electronically controlled voltage regulator T1, a transformer T2, a voltage-doubling capacitor C B , rectifier silicon stack D1, rectifier silicon stack D2 and current limiting resistor Rc; the lightning pulse current generating unit is composed of a pulse energy storage capacitor C, a high-voltage discharge switch G, a waveform forming inductor L and a resistor R, and the forest standing trees to be tested and their clamping mechanism are connected in series in the loop of the energy storage capacitor C, the discharge switch G, the waveform forming inductor L and the resistor R.

[0012] Furthermore, the clamping mechanism includes an insulating plate and a quadrilateral movable clamp installed on the insulating plate with adjustable clamping size, the movable clamp is composed of four retaining bars connected by bolts, the movable clamp is installed in a slide groove opened on the insulating plate, a circular hole with a diameter not less than the diameter of the forest tree is opened in the center of the insulating plate, and a plurality of low-voltage electrodes LV1 to LVN in close contact with the bottom end surface of the forest tree are led out through the circular hole, wherein N is the number of partitions of the forest tree pattern;

[0013] The conductors electrically connecting multiple low-voltage electrodes LV1~LVN to the low-voltage output ports of the lightning pulse current generating units are provided with current sensing coils L1, L2, ..., LN for measuring lightning current in each partition of the forest standing trees, and are used to measure lightning current shunt data Im1, Im2, ..., ImN in each area of ​​the forest standing trees.

[0014] Furthermore, the control unit includes a charging voltage monitoring circuit, a programmable controller and its related control circuits; the charging voltage monitoring circuit receives the signal transmitted by the charging voltage monitoring sensor, and after being processed by the programmable controller and its related control circuits, outputs a control signal to the programmable controller and its related control circuits to control the discharge of the high-voltage discharge switch G of the lightning pulse current generating unit; the programmable controller and its related control circuits also jointly control the connection / disconnection, high-voltage increase / decrease and discharge control of the discharge switch G of the charging process of the forest standing tree lightning shunt characteristic test with the industrial control computer of the lightning pulse current measurement and analysis unit, so as to realize the automatic control of the forest standing tree lightning shunt characteristic test process.

[0015] Furthermore, the lightning pulse current parameter measurement and analysis unit includes pulse current sensors 32-1, 32-2, ..., 32-N, a digital oscilloscope and an industrial control computer; the pulse current sensors 32-1, 32-2, ..., 32-N and the digital oscilloscope jointly measure the lightning shunt characteristics of different areas of the forest standing trees; the industrial control computer processes and analyzes the lightning shunt signals of different areas of the forest standing trees measured by the digital oscilloscope to obtain the forest standing tree lightning zoning including parameters such as forest standing tree moisture content, environmental temperature and humidity, and lightning current point electrical parameters, as well as the shunt characteristics of different zoning areas.

[0016] A method for testing and analyzing the lightning current diversion characteristics of forest standing trees, comprising the following steps:

[0017] (1) Sample selection and processing: Select forest standing tree samples from typical forest areas and process the samples to obtain multiple forest standing tree samples with different temperatures, humidity and moisture contents;

[0018] (2) Select the first forest tree sample S1 with the highest moisture content for testing; the electrodes of the clamping mechanism are electrically connected to the lightning pulse current generating unit, the high-voltage electrode HV is in close contact with the top surface of the forest tree, and the multiple low-voltage electrodes LV1 to LVN are in close contact with the partitions with different textures on the bottom surface of the forest tree;

[0019] 1) Applying lightning current pulses with different peak values ​​to the standing trees in the forest, the lightning pulse current generating unit outputs a preset first discharge current point I1, and correspondingly obtains the shunt data I11, I12, ..., I1N of the standing trees in the forest;

[0020] 2) gradually changing the output current of the lightning pulse current generating unit so that the preset discharge current point changes from I1 to Im, and correspondingly obtaining the diversion data Im1, Im2, ..., ImN of the standing trees in the forest;

[0021] 3) Analyze the lightning current shunt data of forest standing trees I11, I12, ..., I1N to Im1, Im2, ..., ImN. If the deviation between two adjacent shunt data of forest standing trees is less than the required value under the action of lightning current pulses of not less than 5 data points, merge the two adjacent partitions;

[0022] 4) Repeat the test from step 2) to step 4) for the lightning current partition after the forest standing trees are merged, until the lightning current partition of the forest standing tree sample S1 is determined;

[0023] 5) Select the next sample with different moisture content and repeat steps 1) to 5) until the lightning zoning test of all samples with different moisture content is completed;

[0024] (3) Repeat the test process of step (2) for forest standing tree specimens with different temperatures and humidities to obtain lightning current shunting data for each area of ​​the forest standing tree specimens with different temperatures and humidities;

[0025] (4) Statistical analysis was performed on all the lightning diversion test data of standing forest trees to obtain the intrinsic relationship between the lightning diversion zones of standing forest trees, the diversion characteristics, the moisture content of standing forest trees, the temperature and humidity of the climate environment of standing forest trees, and the lightning parameters, thus forming a database of lightning diversion of standing forest trees and its characteristic rules.

[0026] The present invention focuses on the lightning shunt characteristics of lightning struck forest trees, establishes a lightning shunt characteristics test system for forest trees, proposes a lightning shunt characteristics test and analysis method, and according to the natural structural characteristics of forest trees, through the test data of shunt in forest tree partitions under the action of lightning current, uses data statistical methods to finally obtain the zoning characteristics of forest trees and the correlation between the shunt characteristics of lightning current in different partitions and factors such as moisture content, temperature and humidity of forest tree specimens, to form a forest tree lightning shunt characteristics database that simulates the characteristics of forest lightning fires in different regional characteristics, laying a foundation for the research on multi-physics field modeling of lightning strikes on forest combustibles, lightning fire mechanisms and prediction algorithms.

[0027] The present invention adopts an electrode structure of a single integral high-voltage electrode and multiple circular or annular low-voltage electrodes, wherein the structural dimensions of the multiple annular low-voltage electrodes correspond to the structural parameters of forest trees, and by injecting lightning current pulses with different peak values ​​into forest trees, the shunt data of forest trees under the action of lightning current pulses with different peak values ​​can be obtained. The correlation between the shunt characteristics of forest trees under lightning strikes and the climate environment, lightning current action mode and electrical parameters is obtained, providing dynamic electrical characteristics for the multi-physics field modeling calculation of the smoldering and ignition mechanisms caused by lightning strikes on forest trees. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural block diagram of the lightning current shunting characteristic test system of the present invention;

[0029] Figure 2 The circuit principle block diagram of the lightning current shunt characteristic test system of the present invention;

[0030] Figure 3 A clamping mechanism for the lightning current shunting characteristic test of forest standing trees of the present invention;

[0031] Among them, (a) is a stereogram, and (b) is a schematic diagram of the electrode setting on the forest standing trees;

[0032] Figure 4 This is a flow chart of the test and analysis method for lightning current diversion characteristics of standing trees in forests. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0034] join Figure 1 , Figure 2 The forest standing tree lightning shunt characteristic test system of the present invention is composed of a lightning pulse current source 1, forest standing trees 2, a clamping mechanism, a lightning current control and an electrical parameter measurement and analysis unit 3.

[0035] The lightning pulse current source 1 is mainly composed of a controllable high-voltage DC charging power supply 1-1 and a lightning pulse current generating unit 1-2. In actual tests, the charging voltage of the controllable high-voltage DC charging power supply 1-1 to the lightning pulse current generating unit 1-2 is monitored online by the charging voltage monitoring sensor 1-3, and the charging voltage analog quantity is transmitted to the control unit 31 of the lightning current control and electrical parameter measurement and analysis unit 3. The function of the lightning pulse current generating unit 1-2 is to generate a lightning pulse current wave.

[0036] See also Figure 2 , which is the principle circuit of the lightning pulse current source 1. In view of the high voltage environment with extremely high amplitude when the actual lightning strike occurs, the working voltage of the lightning pulse power supply in this application cannot be too low, at least 50kV-100kV or even higher. For this reason, the controllable high-voltage DC charging power supply 1-1 can adopt the usual rectification and filtering charging method, but it is best to adopt the voltage doubling charging method to avoid corona discharge during the experiment, which affects the reliability and stability of the lightning pulse current source.

[0037] like Figure 2 As shown, the controllable high-voltage DC charging power supply 1-1 is mainly composed of an electronically controlled voltage regulator T1, a transformer T2, and a voltage-doubling capacitor C B, rectifier silicon stacks D1 and D2 and current limiting resistor Rc. The lightning pulse current generating unit 1-2 is mainly composed of a pulse energy storage capacitor C, a high-voltage discharge switch G, a waveform forming inductor L and a resistor R, which are electrically connected in series, and the forest standing tree 2 to be tested and its clamping mechanism are connected in series in the loop of the energy storage capacitor C, the discharge switch G, the waveform forming inductor L and the resistor R.

[0038] In order to improve the reliability and credibility of lightning shunt characteristic data of forest standing trees under repeated lightning discharges, the lightning pulse current source ensures that the amplitude of the pulse current flowing through the forest standing trees is not too large. It is recommended to be on the order of several kA. Otherwise, explosion may occur and shunt characteristic data of no less than m (≥5) data points cannot be obtained.

[0039] The function of the lightning current control and electrical parameter measurement and analysis unit 3 is to realize the control of the forest standing tree lightning shunt test and the measurement and analysis of the lightning pulse current electrical parameters. It is mainly composed of a control unit 31 and a lightning pulse current measurement and analysis unit 32. Among them, the control unit 31 is mainly composed of a charging voltage monitoring circuit 31-1, a programmable controller and its related control circuit 31-2. The charging voltage monitoring circuit 31-1 of the control unit 31 receives the signal transmitted by the charging voltage monitoring sensor 1-3, and after being measured and processed by the programmable controller and its related control circuit 31-2, it can output a control signal to the programmable controller and its related control circuit 31-2, so as to discharge the high-voltage discharge switch G of the lightning pulse current generating unit 1-2. In addition, the programmable controller and its related control circuit 31-2 are also combined with the industrial control computer 32-4 of the lightning pulse current measurement and analysis unit 32 to control the connection / disconnection of the charging process of the forest standing tree lightning shunt characteristic test, the high voltage rise / fall and the discharge control of the discharge switch G, so as to realize the automatic control of the forest standing tree lightning shunt characteristic test process.

[0040] The lightning pulse current parameter measurement and analysis unit 32 is mainly composed of pulse current sensors 32-1, 32-2, ..., 32-N, a digital oscilloscope 32-3 and an industrial control computer 32-4. The pulse current sensors 32-1, 32-2, ..., 32-N are combined with the digital oscilloscope 32-3 to measure the lightning shunt characteristics of different areas of forest standing trees; the industrial control computer 32-4 processes and analyzes the lightning shunt signals of different areas of forest standing trees measured by the digital oscilloscope 32-2, so as to obtain the lightning zoning of forest standing trees including parameters such as forest standing tree moisture content, environmental temperature and humidity, and lightning current point electrical parameters, as well as the shunt characteristics of different zonings. In particular, if the number of forest standing tree lightning current zonings is greater than 4, two sets of oscilloscopes or multi-channel data acquisition systems can be used in conjunction with industrial computers for acquisition, recording and analysis.

[0041] See also Figure 3 The clamping mechanism of the forest tree lightning shunting test is to install the forest tree on a mounting fixture having a high-voltage electrode HV and multiple low-voltage electrodes LV, wherein the high-voltage electrode HV is electrically connected to the output high-voltage port of the lightning pulse current generating unit 1-2, and the multiple low-voltage electrodes are respectively electrically connected to the low-voltage ports (or called return electrodes) of the lightning pulse current generating unit 1-2.

[0042] The clamping mechanism of the forest tree is used to fix the forest tree 2, and is composed of an electrode unit and a fixed insulating support mechanism, wherein the electrode unit includes a high-voltage electrode HV and a plurality of circular or annular low-voltage electrodes corresponding to the end surface texture of the forest tree. For a forest tree specimen with a certain end surface structure, the high-voltage electrode HV is a circular electrode with the same size as the end surface of the forest tree, and the size of the plurality of circular or annular low-voltage electrodes corresponding to the end surface texture of the forest tree changes with the change of the lightning partition of the forest tree. The fixed insulating support mechanism includes an insulating plate a1 and a quadrilateral movable clamp a2 installed on the insulating plate a1 and with adjustable clamping size. The movable clamp a2 is composed of four baffles connected by bolts. By adjusting the installation position of each baffle, the clamping of standing trees with different diameters can be achieved. A slide groove is opened on the insulating plate a1, and the movable clamp a2 is installed in the slide groove to change its position to achieve the movement of the movable clamp a2 on the insulating plate. A circular hole with a diameter not less than the diameter of the forest standing trees is opened in the center of the insulating plate. The purpose is to lead out multiple low-voltage electrodes LV1~LVN that are in close contact with the bottom end surface of the forest standing trees, where N is the number of partitions of the forest standing tree texture.

[0043] The wires electrically connected to the low-voltage output ports of the lightning pulse current generating units 1-2 are provided with multiple low-voltage electrodes LV1~LVN in close contact with the bottom ends of the forest trees. Current sensing coils L1, L2, ..., LN for measuring lightning current in each partition of the forest trees are installed to measure lightning current shunt data Im1, Im2, ..., ImN in each area of ​​the forest trees respectively.

[0044] See also Figure 4 , the test and analysis method of forest standing tree lightning diversion characteristics is as follows:

[0045] (1) Sample selection and processing: Select forest standing tree samples from typical forest areas and process the samples, including temperature, humidity, moisture content, etc., to simulate the actual environment of different plants in different seasons and climatic conditions. Prepare forest standing tree samples with different moisture contents, at least 5 samples with different moisture contents (recorded as S1 to S5). The samples can be selected from typical forest areas with different climatic and environmental characteristics (such as Daxinganling, Liangzhou, etc.).

[0046] (2) Select / reselect the forest standing tree sample S1 with the first moisture content for testing;

[0047] Install the forest tree in the clamping mechanism, connect the electrodes of the clamping mechanism to the lightning pulse current generating unit, the high-voltage electrode HV is in close contact with the top surface of the forest tree, and the multiple low-voltage electrodes LV1 to LVN are in close contact with the partitions with different patterns on the bottom surface of the forest tree;

[0048] 1) Apply lightning current pulses with different peak values ​​to standing trees in the forest, select m (≥5) discharge current (or discharge voltage) points, and achieve the output of a preset discharge current peak value through the discharge voltage of the lightning pulse current generating unit 1-2.

[0049] In order to improve the reliability and credibility of lightning shunt characteristic data of forest standing trees under repeated lightning discharges, the lightning pulse current source ensures that the amplitude of the pulse current flowing through the forest standing trees is not too large. It is recommended to be on the order of several kA. Otherwise, explosion may occur and shunt characteristic data of no less than m (≥5) data points cannot be obtained.

[0050] 2) Change the charging voltage of the controllable high-voltage DC charging power supply 1-1 to the energy storage capacitor of the lightning pulse current generating unit 1-2. When the control unit 31 detects that the charging voltage of the energy storage capacitor is greater than or equal to the preset discharge voltage U1, the control unit 31 outputs a discharge pulse to the controllable high-voltage discharge switch G of the lightning pulse current generating unit 1-2, and the lightning pulse current generating unit 1-2 outputs the preset first discharge current point I1, corresponding to the shunt data I11, I12, ..., I1N of the standing trees in the forest. Similarly, change the charging voltage of the controllable high-voltage DC charging power supply 1-1 to the energy storage capacitor of the lightning pulse current generating unit 1-2 until the lightning pulse current generating unit 1-2 outputs the preset first discharge current point Im, corresponding to the shunt data Im1, Im2, ..., ImN of the standing trees in the forest.

[0051] 3) Analyze the lightning current diversion data of standing trees in the forest I11, I12, ..., I1N to Im1, Im2, ..., ImN. If the deviation between two adjacent data points of standing trees in the forest is very small (for example, less than 5%) under the action of lightning current pulses of not less than 5 data points, the two adjacent partitions can be merged.

[0052] 4) Repeat the tests from step 2) to step 4) on the lightning current zones after the forest trees are merged until the lightning current zones of the forest tree specimen S1 are determined.

[0053] 5) Select the next sample with a different moisture content and repeat steps 1) to 5) until the lightning zoning test for all samples with different moisture contents is completed.

[0054] (3) For forest standing tree specimens with different temperatures and humidity, the test method is the same as that for specimens with different moisture contents. The above test process can be repeated to obtain the results.

[0055] (4) Statistical analysis was performed on all the lightning diversion test data of standing forest trees to obtain the intrinsic correlation between the lightning diversion zones and diversion characteristics of standing forest trees and the moisture content of standing forest tree specimens, the temperature and humidity of the forest tree climate environment, and lightning parameters, thus forming a database of lightning diversion of standing forest trees and its characteristic rules.

Claims

1. A forest standing tree lightning current diversion characteristics test system, characterized by: It comprises a lightning pulse current source (1), a forest standing tree (2), a clamping mechanism, a lightning current control unit and an electrical parameter measurement and analysis unit (3); The lightning pulse current source (1) is used to generate lightning pulse current, and comprises a controllable high-voltage direct current charging power supply (1-1) and a lightning pulse current generating unit (1-2); the controllable high-voltage direct current charging power supply (1-1) performs online monitoring of the charging voltage of the lightning pulse current generating unit (1-2) via a charging voltage monitoring sensor (1-3), and transmits the charging voltage analog quantity to a control unit (31) of a lightning current control and electrical parameter measurement and analysis unit (3); The forest standing tree (2) is installed through a clamping mechanism and is electrically connected to the lightning pulse current generating unit (1-2); The clamping mechanism is a mounting fixture having a high-voltage electrode HV and a plurality of low-voltage electrodes LV, the high-voltage electrode HV being a circular electrode having the same size as the end face of a forest tree, the plurality of low-voltage electrodes being circular or annular electrodes corresponding to the texture of the other end face of the forest tree, the high-voltage electrode HV being electrically connected to the output high-voltage port of the lightning pulse current generating unit (1-2), and the plurality of low-voltage electrodes being electrically connected to the low-voltage ports of the lightning pulse current generating unit (1-2); The lightning current control and electrical parameter measurement and analysis unit (3) is used to control a forest standing tree lightning current shunting test and measure and analyze lightning pulse current electrical parameters, and comprises a control unit (31) and a lightning pulse current measurement and analysis unit (32).

2. The forest standing tree lightning current shunting characteristic test system according to claim 1, characterized in that: The controllable high-voltage DC charging power supply (1-1) is composed of an electronically controlled voltage regulator T1, a transformer T2, a voltage multiplier capacitor C B , a rectifier silicon stack D1, a rectifier silicon stack D2 and a current limiting resistor Rc; the lightning pulse current generating unit (1-2) is composed of a pulse energy storage capacitor C, a high-voltage discharge switch G, a waveform forming inductor L and a resistor R, and the forest standing tree (2) to be tested and its clamping mechanism are connected in series in a loop of the energy storage capacitor C, the discharge switch G, the waveform forming inductor L and the resistor R.

3. The forest standing tree lightning current shunting characteristic test system according to claim 1, characterized in that: The clamping mechanism comprises an insulating plate (a1) and a quadrilateral movable clamp (a2) installed on the insulating plate (a1) with an adjustable clamping size, the movable clamp (a2) being composed of four retaining bars connected by bolts, the movable clamp (a2) being installed in a slide groove provided on the insulating plate (a1), a circular hole having a diameter not less than the diameter of a forest tree being provided at the center of the insulating plate, a plurality of low-voltage electrodes LV1 to LVN being in close contact with the bottom end surface of the forest tree being led out through the circular hole, wherein N is the number of partitions of the forest tree grain; Current sensing coils L1, L2, ..., LN for measuring lightning current in each partition of forest standing trees are mounted on the wires electrically connected to the low voltage output ports of the lightning pulse current generating units (1-2) and are used to measure lightning current shunt data Im1, Im2, ..., ImN in each area of ​​the forest standing trees.

4. The forest standing tree lightning current shunting characteristic test system according to claim 1, characterized in that: The control unit (31) comprises a charging voltage monitoring circuit (31-1), a programmable controller and its related control circuit (31-2); the charging voltage monitoring circuit (31-1) receives a signal transmitted by a charging voltage monitoring sensor (1-3), processes the signal through the programmable controller and its related control circuit (31-2), and outputs a control signal to the programmable controller and its related control circuit (31-2) to control the discharge of a high-voltage discharge switch G of a lightning pulse current generating unit (1-2); the programmable controller and its related control circuit (31-2) also work with an industrial control computer (32-4) of a lightning pulse current measuring and analyzing unit (32) to control the connection / disconnection, high-voltage increase / decrease, and discharge control of the discharge switch G during the charging process of a forest standing tree lightning current shunt characteristic test, thereby realizing automatic control of the forest standing tree lightning current shunt characteristic test process.

5. The forest standing tree lightning current shunting characteristic test system according to claim 1, characterized in that: The lightning pulse current parameter measurement and analysis unit (32) comprises pulse current sensors (32-1), (32-2), ..., (32-N), a digital oscilloscope (32-3) and an industrial control computer (32-4); the pulse current sensors (32-1), (32-2), ..., (32-N) and the digital oscilloscope (32-3) jointly measure the lightning shunt characteristics of different areas of forest standing trees; the industrial control computer (32-4) processes and analyzes the lightning shunt signals of different areas of forest standing trees measured by the digital oscilloscope (32-2) to obtain forest standing tree lightning zoning including parameters such as forest standing tree moisture content, environmental temperature and humidity, and lightning current point electrical parameters, and shunt characteristics of different zoning areas.

6. A test and analysis method for the lightning shunt characteristics of forest standing trees based on the test system of claim 1, characterized in that The steps include: (1) Sample selection and processing: Select forest standing tree samples from typical forest areas and process the samples to obtain multiple forest standing tree samples with different temperatures, humidity and moisture contents; (2) Select the first forest tree sample S1 with the highest moisture content for testing; the electrodes of the clamping mechanism are electrically connected to the lightning pulse current generating unit, the high-voltage electrode HV is in close contact with the top surface of the forest tree, and the multiple low-voltage electrodes LV1 to LVN are in close contact with the partitions with different textures on the bottom surface of the forest tree; 1) applying lightning current pulses with different peak values ​​to the standing trees in the forest, and the lightning pulse current generating unit (1-2) outputs a preset first discharge current point I1, and correspondingly obtains the current diversion data I11, I12, ..., I1N of the standing trees in the forest; 2) gradually changing the output current of the lightning pulse current generating unit (1-2) so that the preset discharge current point changes from I1 to Im, and correspondingly obtaining the diversion data Im1, Im2, ..., ImN of the standing trees in the forest; 3) Analyze the lightning current shunt data of forest standing trees I11, I12, ..., I1N to Im1, Im2, ..., ImN. If the deviation between two adjacent shunt data of forest standing trees is less than the required value under the action of lightning current pulses of not less than 5 data points, merge the two adjacent partitions; 4) Repeat the test from step 2) to step 4) for the lightning current partition after the forest standing trees are merged, until the lightning current partition of the forest standing tree sample S1 is determined; 5) Select the next sample with different moisture content and repeat steps 1) to 5) until the lightning zoning test of all samples with different moisture content is completed; (3) Repeat the test process of step (2) for forest standing tree specimens with different temperatures and humidities to obtain lightning current shunting data for each area of ​​the forest standing tree specimens with different temperatures and humidities; (4) Statistical analysis was performed on all the lightning diversion test data of standing forest trees to obtain the intrinsic relationship between the lightning diversion zones of standing forest trees, the diversion characteristics, the moisture content of standing forest trees, the temperature and humidity of the climate environment of standing forest trees, and the lightning parameters, thus forming a database of lightning diversion of standing forest trees and its characteristic rules.

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