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

Abstract

This invention discloses a test system for the lightning current characteristics of forest standing trees, as well as a method for testing and analyzing lightning current characteristics. The test system includes a lightning pulse current source, forest standing trees, a clamping mechanism, and a unit for controlling the lightning current and measuring and analyzing its electrical parameters. By dividing and segmenting forest standing trees with approximately the same structure into regions, lightning current tests are conducted on forest standing tree modules with radial and axial structures under the action of lightning current. The correlation between the dynamic electrical characteristics of forest standing tree modules and factors such as moisture content, temperature, and humidity under different lightning current injection methods is obtained, forming a database of lightning current characteristics of forest standing tree modules simulating the characteristics of forest lightning-induced fires in different regions. At the same time, a complex topological circuit network of forest standing trees is established to explain the mechanism of lightning conduction in forest standing trees, laying the foundation for the research on multi-physics modeling of lightning strikes on forest combustibles, lightning-induced fire mechanisms, and prediction algorithms.

Description

Technical Field

[0001] This invention relates to a test method for the characteristics of forest lightning fires, and particularly to a test system for the lightning current characteristics of standing trees in forests, as well as a test and analysis method for lightning current characteristics. Background Technology

[0002] Lightning is a multiple, continuous, time-series discharge process. In this process, the first lightning strike plays a crucial role, involving the adhesion process between the lightning strike and combustible materials such as forest vegetation and standing trees. It directly affects the lightning current characteristics in these materials, including vegetation, standing trees, and humus layers, and is of great significance for theoretical research on the smoldering or ignition mechanisms of forest lightning strikes. Existing research on lightning-induced fires mainly relies on predictive models built from historical lightning-induced fire data. These models predict the probability and location of lightning-induced fires based on meteorological conditions and forest conditions. However, there is a dearth of literature on the generation and development of lightning-induced fires, focusing on the physical processes or mechanisms of lightning adhesion and lightning current to forest combustibles. Therefore, the accuracy of existing predictive models for lightning strike warnings is difficult to guarantee. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a test system for the lightning current characteristics of standing trees in forests, as well as a test and analysis method for lightning current characteristics. This system obtains the correlation between the dynamic characteristics of standing trees in forests under lightning strikes and the climate environment, the mode of lightning current action, and electrical parameters. It also provides the distribution law of dynamic characteristics of combustible standing trees in forests for multi-physics field modeling and calculation of smoldering and ignition mechanisms caused by lightning strikes.

[0004] This invention is achieved through the following technical solution:

[0005] A test system for lightning current characteristics of standing trees in forests includes a lightning pulse current source, standing trees in forests, a clamping mechanism, and a unit for controlling the lightning current and measuring and analyzing its electrical parameters.

[0006] The lightning pulse current source includes a controllable high-voltage DC charging power supply and a lightning pulse current generating unit. The charging voltage of the lightning pulse current generating unit is monitored by a charging voltage monitoring sensor, and the analog charging voltage is transmitted to the control unit of the lightning current control and its electrical parameter measurement and analysis unit.

[0007] The standing trees in the forest are installed and fixed by a clamping mechanism, which includes a high-voltage electrode HV and a low-voltage electrode LV. The standing tree module is installed between the high-voltage electrode HV and the low-voltage electrode LV according to the axial and radial injection of lightning current. The high-voltage electrode HV is electrically connected to the output high-voltage port of the lightning pulse current generating unit, and the low-voltage electrode LV is electrically connected to the low-voltage port of the lightning pulse current generating unit.

[0008] The lightning current control and its electrical parameter measurement and analysis unit realizes the control of the lightning current test of standing trees in the forest and the measurement and analysis of the electrical parameters of the lightning pulse current, including the control unit 31 and the lightning pulse current measurement and analysis unit control circuit.

[0009] Furthermore, the controllable high-voltage DC charging power supply consists of an electronically controlled voltage regulator T1, a transformer T2, and a voltage multiplier capacitor C. B The system consists of rectifier silicon stacks D1 and D2 and a 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 connected in series, and the forest standing tree under test and its clamping mechanism are connected in series in the circuit of the energy storage capacitor, the discharge switch, the waveform forming inductor and the resistor.

[0010] Furthermore, the clamping mechanism includes a metal plate and a quadrilateral movable clamp with adjustable size mounted on the metal plate. The movable clamp consists of four stop bars connected by bolts. A current induction coil L1 for measuring the lightning current flowing through forest trees is sleeved on the wire electrically connected to the low-voltage output port of the lightning pulse current generating unit. This coil is used to measure the lightning current waveform flowing through the forest tree module sample.

[0011] Furthermore, the high-voltage electrode HV is a rectangular, square, or circular electrode that matches the end face of the forest standing tree specimen, and the low-voltage electrode LV is a metal electrode with the same structural dimensions as the high-voltage electrode HV.

[0012] Furthermore, the control unit includes a charging voltage monitoring circuit, a programmable logic controller (PLC) and related control circuits;

[0013] The charging voltage monitoring circuit receives the signal transmitted from the charging voltage monitoring sensor, and after processing 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 switch of the lightning pulse current generating unit. The programmable controller and its related control circuits are also combined with the industrial control computer of the lightning pulse current measurement and analysis unit control circuit to control the connection / disconnection, high voltage rise / fall, and discharge control of the discharge switch G in the charging process of the forest standing tree lightning current characteristic test, so as to realize the automatic control of the forest standing tree lightning current characteristic test process.

[0014] Furthermore, the control circuit of the lightning pulse current measurement and analysis unit includes a pulse current sensor, a pulse voltage sensor, a digital oscilloscope, and an industrial control computer;

[0015] The pulse current sensor, pulse voltage sensor, and digital oscilloscope are combined to obtain the dynamic impedance characteristics of the forest standing tree specimen under the action of lightning current based on the current flowing through the forest standing tree module specimen and the voltage across its two ends. The industrial control computer processes and analyzes the data transmitted by the digital oscilloscope to obtain the correlation between the dynamic impedance characteristics of the forest standing tree module and the electrical parameters including moisture content, ambient temperature and humidity, and lightning current.

[0016] A test and analysis method for the lightning strike diversion characteristics of standing trees in forests includes the following steps:

[0017] (1) Sample selection and treatment: Forest standing tree module specimens with different moisture contents, temperature and humidity were prepared, and radial and axial forest standing tree module specimens were treated.

[0018] (2) Select the first forest standing tree module specimen S1 with the highest moisture content for the test;

[0019] 1) Connect the test sample to the output terminal of the lightning pulse current generating unit, apply lightning current pulses with different peak values ​​to the forest tree module in the radial and axial directions, and measure the lightning current characteristic data of the forest tree module through a pulse current sensor, a pulse voltage sensor, an oscilloscope and a computer.

[0020] 2) Change the discharge voltage of the lightning pulse current generating unit. The lightning pulse current generating unit outputs the preset first discharge current point I1, and record the voltage U1 across the forest tree module. Change the charging voltage of the controllable high voltage DC charging power supply to the energy storage capacitor of the lightning pulse current generating unit until the lightning pulse current generating unit outputs the preset current point data Im, and obtain the lightning current data Im and impulse voltage data Um of the forest tree module.

[0021] 3) Analyze the lightning current data I1, I2, ..., Im and the impulse voltage data U1, U2, ..., Um of the forest standing tree module to obtain the lightning dynamic characteristics of the forest standing tree module under a set moisture content.

[0022] 4) Select the next forest standing tree module sample with different moisture content and repeat steps 1) to 3) until the lightning dynamic characteristic test of all samples with different moisture contents is completed.

[0023] (3) The above test process can be repeated for forest standing tree module specimens with different temperatures and humidity. If there are other influencing factors such as air pressure, repeat steps 1) to 3) above to obtain the lightning dynamic characteristics of forest standing tree modules with different temperatures and humidity.

[0024] (4) Statistical analysis of all forest standing tree module lightning current test data was conducted to establish a forest standing tree topology circuit network and to clearly explain the mechanism of lightning conduction in forest standing trees. At the same time, the correlation between the lightning characteristics of forest standing trees and the moisture content and temperature and humidity of forest standing trees was obtained, forming a forest standing tree lightning current database and characteristic laws.

[0025] This invention focuses on the lightning current characteristics of forest standing trees struck by lightning, a test system for the lightning current characteristics of forest standing trees, and a test and analysis method for lightning current characteristics. By dividing and segmenting forest standing trees with approximately the same structure into regions, lightning current tests are conducted on forest standing tree modules with radial and axial structures under the action of lightning current. The correlation between the dynamic electrical characteristics of forest standing tree modules and factors such as moisture content, temperature, and humidity under different lightning current injection methods is obtained, forming a database of lightning current characteristics of forest standing tree modules simulating the characteristics of forest lightning-induced fires in different regions. At the same time, a complex topological circuit network of forest standing trees is established to explain the mechanism of lightning conduction in forest standing trees, laying the foundation for the research on multi-physics modeling of forest combustibles struck by lightning, lightning-induced fire mechanism, and prediction algorithms. Attached Figure Description

[0026] Figure 1 This is a structural block diagram of the lightning current characteristic test system of the present invention;

[0027] Figure 2 This is a circuit block diagram of the lightning current characteristic test system of the present invention;

[0028] Figure 3 This invention relates to a forest standing tree module test specimen and a lightning characteristic test clamping mechanism.

[0029] Among them, (a) is an exploded view of the forest standing tree structure; (b) is a schematic diagram of current injection along the axial direction of the forest standing tree; (c) is a schematic diagram of current injection along the radial direction of the forest standing tree; and (d) is a three-dimensional view of the clamping mechanism.

[0030] Figure 4 A flowchart for the experimental and analytical methods of lightning current characteristics of standing trees in forests. Detailed Implementation

[0031] The present invention will be further described in detail below with reference to specific embodiments. These descriptions are for explanation purposes only and are not intended to limit the scope of the invention.

[0032] join Figure 1 , Figure 2 The forest standing tree lightning current characteristic test system of the present invention consists of a lightning pulse current source 1, forest standing trees 2, clamping mechanism, lightning current control and its electrical parameter measurement and analysis unit 3.

[0033] The lightning pulse current source 1 mainly consists 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 analog charging voltage is transmitted to the control unit 31 of the lightning current control and its electrical parameter measurement and analysis unit 3.

[0034] See Figure 2 The principle circuit of the lightning pulse current source 1 for testing the lightning current characteristics of standing trees in forests according to this invention mainly consists of two parts: a controllable high-voltage DC charging power supply 1-1 and a lightning pulse current generating unit 1-2. Given the extremely high amplitude and high voltage environment during actual lightning strikes, the operating voltage of the lightning pulse power supply in this application cannot be too low, at least 50kV-100kV or even higher. Therefore, the controllable high-voltage DC charging power supply 1-1 can adopt a conventional rectification and filtering charging method, but it is best to use a voltage multiplier charging method to avoid corona discharge during the experiment, which would affect the reliability and stability of the lightning pulse current source. The controllable high-voltage DC charging power supply 1-1 mainly consists of an electronically controlled voltage regulator T1, a transformer T2, and a voltage multiplier capacitor C. B The system consists of rectifier silicon stacks D1 and D2 and a current-limiting resistor Rc. The function of the lightning pulse current generating unit 1-2 is to generate lightning pulse current waves. The lightning pulse current generating unit mainly consists of a pulse energy storage capacitor C, a high-voltage discharge switch G, a waveform forming inductor L, and a resistor R. They are electrically connected in series, and the forest standing trees under test and their clamping mechanism are connected in series in the circuit of the energy storage capacitor, the discharge switch, the waveform forming inductor, and the resistor.

[0035] like Figure 3 As shown, the clamping mechanism for the forest standing tree lightning current test involves mounting the forest standing tree 2 onto a special clamp with a pair of high-voltage electrodes HV and low-voltage electrodes LV, as follows. Figure 3 In (b) and (c), the forest standing module is installed between the high-voltage electrode HV and the low-voltage electrode LV according to the axial and radial injection of lightning current, respectively. 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 low-voltage electrode LV is electrically connected to the low-voltage port (or return electrode) of the lightning pulse current generating unit 1-2.

[0036] like Figure 3As shown in (a), the forest standing tree sample is a specimen prepared from rectangular or circular forest standing tree modules with certain length, width, and height, taken from the heartwood, sapwood, cambium, phloem, and epidermis of the forest standing tree, based on the natural structural characteristics of the forest standing tree. The tested forest standing tree specimen is installed between a high-voltage electrode and a low-voltage electrode, wherein the high-voltage electrode is a rectangular, square, or circular electrode that matches the end face of the forest standing tree specimen, and the low-voltage electrode can be a metal electrode with the same structural dimensions as the high-voltage electrode or a large metal electrode plate can be used as the low-voltage electrode.

[0037] like Figure 3 As shown in (d), the clamping mechanism is used to fix the standing trees 2. It includes a metal plate a1 and a movable quadrilateral clamp a2 with adjustable dimensions, mounted on the metal plate a1. The movable clamp a2 consists of four bolted bars. By adjusting the installation position of each bar, trees of different diameters can be clamped. The metal plate can also serve as the low-voltage electrode of the standing tree clamping mechanism. A current induction coil L1 for measuring the lightning current flowing through the standing trees is sleeved on the wire electrically connected to the low-voltage output port of the lightning pulse current generating unit on the metal plate low-voltage electrode LV. The current Im is represented by m (≥5) in the table below, which indicates the number of data points of the lightning current, used to measure the lightning current waveform flowing through the standing tree module sample.

[0038] The function of the lightning current control and electrical parameter measurement and analysis unit 3 is to control the lightning current test of standing trees in the forest and to measure and analyze the electrical parameters of the lightning pulse current. It mainly consists of a control unit 31 and a lightning pulse current measurement and analysis unit 32. The control unit 31 mainly consists of a charging voltage monitoring circuit 31-1 and a programmable logic controller (PLC) and its related control circuits 31-2. The charging voltage monitoring circuit 31-1 receives the signal transmitted from the charging voltage monitoring sensor 1-3, and after processing by the PLC and its related control circuits 31-2, it can output a control signal to the PLC and its related control circuits 31-2 to control the discharge switch of the lightning pulse current generating unit 1-2. Furthermore, the PLC and its related control circuits 31-2, in conjunction with the industrial control computer 32-4 of the lightning pulse current measurement and analysis unit 32, control the connection / disconnection of the charging process, the rise / fall of the high voltage, and the discharge control of the discharge switch G in the lightning current characteristic test of standing trees in the forest, realizing the automatic control of the lightning current characteristic test process of standing trees in the forest.

[0039] The lightning pulse current measurement and analysis unit 32 mainly consists of a pulse current sensor 32-1, a pulse voltage sensor 32-2, a digital oscilloscope 32-3, and an industrial control computer 32-4. The pulse voltage sensor 32-2 measures the pulse voltage across the sample when current flows through it. The pulse current sensor 32-1, pulse voltage sensor 32-2, and digital oscilloscope 32-3 work together to obtain the dynamic impedance characteristics of the forest tree module sample under lightning current based on the current flowing through it and the voltage across it. The industrial control computer 32-4 processes and analyzes the data transmitted from the digital oscilloscope 32-3 to obtain the correlation between the dynamic impedance characteristics of the forest tree module and parameters including moisture content, ambient temperature and humidity, and lightning current.

[0040] See Figure 4 Experimental and analytical methods for lightning current characteristics of standing trees in forests. The specific experimental and analytical procedures are as follows:

[0041] (1) Sample selection and treatment: Prepare forest standing tree module specimens with different moisture contents, and treat the radial and axial forest standing tree module specimens. There are at least 5 specimens with different moisture contents (denoted as S1 to S5).

[0042] The test samples can be selected from typical forests with different climatic characteristics (such as the Greater Khingan Mountains and Liangzhou). The data also includes moisture content, temperature, and humidity to simulate the actual environment of different plants under different seasons and climatic conditions.

[0043] (2) Select the first forest standing tree module specimen S1 with the highest moisture content for the test;

[0044] 1) Connect the test sample to the output terminal of the lightning pulse current generating unit, apply lightning current pulses with different peak values ​​to the forest tree module in the radial and axial directions, and measure the lightning current characteristic data of the forest tree module through the pulse current sensor, pulse voltage sensor, oscilloscope and computer; select m (≥5) discharge current (or discharge voltage) points, and realize the output of the preset discharge current peak value through the discharge voltage of lightning pulse current generating unit 1-2.

[0045] To improve the reliability and credibility of lightning current characteristic data for forest trees under repeated lightning strikes, the lightning pulse current source should ensure that the amplitude of the pulse current flowing through the forest trees is not too large, preferably in the range of several kA. Otherwise, the trees may burst and it will be impossible to obtain flow characteristic data of no less than m (≥5) data points.

[0046] 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 of the lightning pulse current generating unit 1-2. The lightning pulse current generating unit 1-2 outputs the preset first discharge current point I1, and the voltage U1 across the forest tree module is recorded. 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 current point Im, corresponding to the lightning current data Im and impulse voltage data Um of the forest tree module.

[0047] 3) Analyze the lightning current data I1, I2, ..., Im and the impulse voltage data U1, U2, ..., Um of the forest standing tree module to obtain the lightning dynamic characteristics of the forest standing tree module under a set moisture content.

[0048] 4) Select the next forest standing tree module sample with different moisture content and repeat steps 1) to 3) until all samples with different moisture contents have been tested for lightning dynamic characteristics.

[0049] (3) For forest standing tree module specimens with different temperatures and humidity, the test method is the same as that for module specimens with different moisture contents. The above test process can be repeated to obtain the results. If there are other influencing factors such as air pressure, the above process can also be repeated to obtain the laws relating to the lightning dynamic characteristics of forest standing tree modules.

[0050] (4) Statistical analysis was conducted on all forest standing tree module lightning current test data to establish a forest standing tree topology circuit network and elucidate the mechanism of lightning conduction in forest standing trees. Simultaneously, the correlation between forest standing tree lightning characteristics and factors such as forest standing tree moisture content and forest standing tree climate environment (temperature, humidity, wind speed, etc.) was obtained, forming a forest standing tree lightning current database and characteristic patterns. A multi-factor regression method was adopted to form an analytical method for the dynamic resistance characteristics of wood, laying the foundation for lightning strike or model establishment and lightning fire prediction.

Claims

1. A test system for the lightning current characteristics of standing trees in a forest, characterized in that: Includes a lightning pulse current source (1), standing trees in the forest (2), a clamping mechanism, and a lightning current control and electrical parameter measurement and analysis unit (3); The lightning pulse current source (1) includes a controllable high voltage DC charging power supply (1-1) and a lightning pulse current generating unit (1-2). 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 by a charging voltage monitoring sensor (1-3), and the analog quantity of the charging voltage is transmitted to the control unit (31) of the lightning current control and its electrical parameter measurement and analysis unit (3). The standing trees (2) are installed and fixed by a clamping mechanism, which includes a high-voltage electrode HV and a low-voltage electrode LV. The standing tree module is installed between the high-voltage electrode HV and the low-voltage electrode LV according to the axial and radial injection of lightning current. 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 low-voltage electrode LV is electrically connected to the low-voltage port of the lightning pulse current generating unit (1-2). The lightning current control and its electrical parameter measurement and analysis unit (3) realizes the control of the lightning current test of standing trees in the forest and the measurement and analysis of the electrical parameters of the lightning pulse current, including the control unit (31) and the lightning pulse current measurement and analysis unit (32).

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

3. The forest standing tree lightning current characteristic test system according to claim 1, characterized in that: The clamping mechanism includes a metal plate (a1) and a movable quadrilateral clamp (a2) with adjustable size mounted on the metal plate (a1). The movable clamp (a2) consists of four stop bars connected by bolts. A current induction coil L1 for measuring the lightning current flowing through forest trees is sleeved on the wire electrically connected to the low-voltage output port of the lightning pulse current generating unit. This coil is used to measure the lightning current waveform flowing through the forest tree module sample.

4. The forest standing tree lightning current characteristic test system according to claim 1, characterized in that: The high-voltage electrode HV is a rectangular, square, or circular electrode that matches the end face of the forest standing tree specimen, and the low-voltage electrode LV is a metal electrode with the same structural dimensions as the high-voltage electrode HV.

5. The forest standing tree lightning current characteristic test system according to claim 1, characterized in that: The control unit (31) includes 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 the signal transmitted from the charging voltage monitoring sensor (1-3), and after processing by the programmable controller and its related control circuit (31-2), outputs a control signal to the programmable controller and its related control circuit (31-2) to control the discharge switch of the lightning pulse current generating unit (1-2) for discharge control; the programmable controller and its related control circuit (31-2) also work together with the industrial control computer (32-4) of the lightning pulse current measurement and analysis unit (32) to control the connection / disconnection, high voltage rise / fall and discharge control of the charging process of the forest standing tree lightning current characteristic test, and realize the automatic control of the forest standing tree lightning current characteristic test process.

6. The forest standing tree lightning current characteristic test system according to claim 1, characterized in that: The lightning pulse current measurement and analysis unit (32) includes a pulse current sensor (32-1), a pulse voltage sensor (32-2), a digital oscilloscope (32-3), and an industrial control computer (32-4); The pulse current sensor (32-1), pulse voltage sensor (32-2), and digital oscilloscope (32-3) are combined to obtain the dynamic impedance characteristics of forest standing tree specimens under lightning current based on the current flowing through the specimens with different moisture contents, temperatures, and humidity levels and the voltage across them. The industrial control computer (32-4) processes and analyzes the data transmitted by the digital oscilloscope (32-3) to obtain the correlation between the dynamic impedance characteristics of the forest standing tree module and electrical parameters including moisture content, ambient temperature and humidity, and lightning current.

7. A test and analysis method for the lightning strike diversion characteristics of standing trees in forests based on the test system of claim 6, characterized in that... Includes the following steps: (1) Sample selection and treatment: Forest standing tree module specimens with different moisture contents, temperature and humidity were prepared, and radial and axial forest standing tree module specimens were treated. (2) Select the first forest standing tree module specimen S1 with the highest moisture content for the test; 1) Connect the test sample to the output terminal of the lightning pulse current generating unit, apply lightning current pulses with different peak values ​​to the forest tree module in the radial and axial directions, and measure the lightning current characteristic data of the forest tree module through a pulse current sensor, a pulse voltage sensor, an oscilloscope and a computer. 2) Change the discharge voltage 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. Record the voltage U1 across the forest standing tree module. 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 current point data Im, and obtain the lightning current data Im and impulse voltage data Um of the forest standing tree module. 3) Analyze the lightning current data I1, I2, ..., Im and the impulse voltage data U1, U2, ..., Um of the forest standing tree module to obtain the lightning dynamic characteristics of the forest standing tree module under a set moisture content. 4) Select the next forest standing tree module sample with different moisture content and repeat steps 1) to 3) until the lightning dynamic characteristic test of all samples with different moisture contents is completed. (3) Repeat steps 1) to 3) above for forest standing tree module samples with different temperatures and humidity to obtain the lightning dynamic characteristics of forest standing tree modules with different temperatures and humidity. (4) Statistical analysis of all forest standing tree module lightning current test data was conducted to establish a forest standing tree topology circuit network and to clearly explain the mechanism of lightning conduction in forest standing trees. At the same time, the correlation between the lightning characteristics of forest standing trees and the moisture content and temperature and humidity of forest standing trees was obtained, forming a forest standing tree lightning current database and characteristic laws.

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