A forest overhead line electrical fire comprehensive test platform and method

Abstract

This invention relates to the field of electrical fire simulation testing technology, and discloses a comprehensive testing platform and method for electrical fires on overhead power lines in forests. The platform includes a high-voltage testing unit, a low-voltage testing unit, a fault simulation and control unit, a data acquisition and recording unit, an environmental control unit, and a central control and protection unit. The high-voltage testing unit supports single-phase tree contact, conductor drooping grounding, smoke grounding, and phase-to-phase tree contact short-circuit tests at 35kV and 10kV voltage levels. The low-voltage testing unit supports 380V phase-to-phase metallic short-circuit tests. The fault simulation and control unit uses a PID closed-loop controlled robotic arm tree-controlling system to simulate tree swaying. The environmental control unit can adjust temperature and humidity and actively exhaust smoke. This invention solves the problems of incomplete voltage level coverage, limited fault types, low control accuracy, limited data acquisition dimensions, and insufficient safety protection in existing technologies. It can be used for research on the mechanism of forest electrical fires, accident investigation, and the development of prevention and control technologies.

Description

Technical Field

[0001] This invention relates to the field of electrical fire simulation testing technology, specifically to a comprehensive testing platform and method for electrical fires on forest overhead power lines. Background Technology

[0002] Overhead power transmission lines are widely distributed in forests, and electrical faults along their routes can easily trigger forest fires, causing significant casualties and property damage. In recent years, many major forest fires have been closely related to electrical faults in overhead power transmission lines. Therefore, researching the mechanisms, prevention and control technologies, and accident investigation methods for electrical fires caused by overhead power lines in forests is of significant practical importance.

[0003] In the existing technology, there are some electrical fault simulation test devices. For example, the patent "A Low-Voltage Fire Test System and Method in Forest and Pastoral Areas" (202310506602.3) discloses a 380V / 400V low-voltage fire test system that can simulate faults such as single-phase grounding and single-phase open circuit. Another example is the patent "A System and Method for Simulating Wildfire Flame Fault Data under Overhead Lines" (202410831391.5), which discloses a test system simulating wildfire flames bridging with lines at a 10kV voltage level. In addition, research institutions such as Chengdu University of Technology have also published relevant research on a 400V overhead line vegetation contact fault simulation test platform.

[0004] However, the aforementioned existing technologies still have the following technical defects:

[0005] 1) Incomplete voltage level coverage. Existing technologies are either limited to low voltage levels of 380V / 400V, which cannot simulate the discharge characteristics and ignition mechanism of high voltage (10kV and above) electrical faults; or they only cover a single high voltage level (such as 10kV), lacking the ability to simulate higher voltage levels (such as 35kV), making it difficult to fully reflect the fault characteristics of different voltage levels of actual transmission lines.

[0006] 2) Limited Fault Types and Lack of System Integration. Existing technologies typically simulate only single fault types, such as single-phase grounding, open circuits, or wildfire flames, lacking system integration for multiple fault types such as single-phase tree contact, single-phase conductor drooping to ground, single-phase smoke grounding, and phase-to-phase tree contact short circuits. The causes of forest electrical fires are complex and diverse, and existing single-fault simulation devices are insufficient to meet the needs of comprehensive research.

[0007] 3) Low precision in variable control. Current technologies for controlling key physical variables such as conductor height, phase spacing, and the degree of contact between trees and conductors mostly rely on manual or simple mechanical adjustments. This results in low precision and automation, making it difficult to meet the needs of refined testing. In particular, existing technologies lack effective methods for dynamically simulating the swaying of trees under wind conditions.

[0008] 4) Limited data acquisition dimensions. Existing technologies typically only collect electrical parameters (voltage, current, waveform) or perform video recordings alone. This makes it difficult to perform high-precision synchronous correlation analysis between changes in electrical parameters and the arc discharge process, vegetation temperature rise, and ignition moment, resulting in a lack of in-depth research on the mechanisms of electrical fire incubation, occurrence, and development.

[0009] 5) Lack of environmental control capabilities. Most existing experimental devices are conducted in ordinary indoor environments, which cannot simulate the effects of different temperature and humidity conditions on electrical faults and vegetation ignition, nor can they effectively handle the smoke generated during the experiments.

[0010] Therefore, there is an urgent need to provide an integrated test platform that can realistically, safely, and controllably simulate various electrical faults of overhead power transmission lines and their entire process of igniting vegetation in complex forest environments, in order to solve the above-mentioned technical problems. Summary of the Invention

[0011] The purpose of this invention is to provide a comprehensive testing platform and method for electrical fires on overhead power lines in forests, addressing the technical problems in existing technologies such as incomplete voltage level coverage, limited fault types, low variable control accuracy, single data acquisition dimension, insufficient safety protection, and lack of environmental control capabilities. The technical solution is as follows:

[0012] A comprehensive test platform for electrical fires on overhead power lines in forests includes: a high-voltage test unit, a low-voltage test unit, a power supply and distribution unit, a fault simulation and control unit, a data acquisition and recording unit, an image acquisition unit, an environmental control unit, and a central control and protection unit.

[0013] High voltage test unit: used to conduct electrical fault simulation tests at voltage levels of 35kV and 10kV, including single-phase ground fault test and phase-to-phase short circuit fault test, wherein the single-phase ground fault test includes single-phase tree contact test, single-phase conductor drooping ground test and single-phase flue gas grounding test;

[0014] Low-voltage test unit: used to conduct electrical fault simulation tests at a voltage level of 380V, including phase-to-phase metallic short-circuit tests;

[0015] The output terminals of the high-voltage test unit and the low-voltage test unit are respectively connected to the test leads in the fault simulation and control unit;

[0016] Power supply and distribution unit: including multi-voltage level transformer group and switch cabinet group, used to provide test power supply with different voltage levels and different neutral point grounding methods for the high voltage test unit and the low voltage test unit;

[0017] Fault simulation and control unit: including a robotic arm tree control system and a wire lifting and spacing adjustment mechanism, used to automatically control variable parameters during the test process and simulate electrical faults under different working conditions. The robotic arm tree control system adopts PID closed-loop control to control the contact state between the tree and the wire and simulate the swaying of the tree under the action of wind.

[0018] Data acquisition and recording unit: includes a multi-channel waveform recording device and a waveform analysis system, used to acquire, record and analyze voltage and current waveforms and electrical parameters during the test in real time; the input terminal of the data acquisition and recording unit is connected to the voltage and current sampling terminals of the high voltage test unit and the low voltage test unit respectively, and its output terminal is communicatively connected to the data input terminal of the central control and protection unit.

[0019] Image acquisition unit: includes a high-speed camera system and a dual-spectrum monitoring system, used to capture visible light and infrared images of electrical faults, arc breakdowns, and vegetation ignition processes; the output of the image acquisition unit is communicatively connected to the data input of the central control and protection unit;

[0020] Environmental control unit: includes temperature and humidity control system and smoke exhaust device, used to regulate the temperature and humidity of the test environment and remove smoke generated by combustion; its sensors are connected to the input terminal of the central control and protection unit.

[0021] Central control and protection unit: includes a multi-functional console and centralized control software, used to centrally monitor the operating status of each unit, remotely control the test process, and has multiple safety protection functions; the control signal output terminal of the central control and protection unit is connected to the control terminals of the power supply and distribution unit, high voltage test unit, low voltage test unit, fault simulation and control unit, and environmental control unit respectively, for sending control commands.

[0022] A comprehensive test method for electrical fires on forest overhead power lines, applied to the aforementioned comprehensive test platform for electrical fires on forest overhead power lines, includes the following steps:

[0023] Step S1: According to the test requirements, set the test parameters through the central control and protection unit, including selecting the voltage level, fault type, and ambient temperature and humidity;

[0024] Step S2: Adjust the temperature and humidity of the test area to the set values ​​using the environmental control unit;

[0025] Step S3: Adjust the conductor height, phase spacing, and relative position of trees and conductors through the fault simulation and control unit;

[0026] Step S4: The central control and protection unit controls the power supply and distribution unit to supply power to the high-voltage test unit or the low-voltage test unit;

[0027] Step S5: Perform a fault simulation test by controlling the tree to contact the wire through the robotic arm tree control system to trigger a single-phase grounding or phase-to-phase short circuit fault;

[0028] Step S6: The voltage and current waveforms during the fault process are acquired in real time through the data acquisition and waveform recording unit, and the visible light image and infrared thermal image of the fault process are acquired synchronously through the image acquisition unit.

[0029] Step S7: Upon detecting a fault or vegetation ignition, the central control and protection unit automatically cuts off the power supply, thus ending the test.

[0030] Step S8: Remove the smoke from the test area using the smoke extraction device.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. This invention covers three voltage levels simultaneously: 35kV high voltage, 10kV medium voltage, and 380V low voltage. It can comprehensively simulate the electrical fault characteristics of overhead lines at different voltage levels, filling the gap in high voltage level test platforms. It also integrates multiple fault types such as single-phase tree contact, single-phase conductor drooping to ground, single-phase smoke grounding, phase-to-phase tree contact short circuit, and phase-to-phase metallic short circuit, which can comprehensively cover all possible causes of forest electrical fires and meet the needs of comprehensive research.

[0033] 2. This invention employs a PID closed-loop control robotic arm tree control system, which can simulate the swaying of trees under wind force, achieving refined and automated control of the dynamic contact process of "conductor trees," thus improving the repeatability and accuracy of the experiment. It also integrates high-speed electrical waveform recording, 4K high-speed imaging, and dual-spectrum infrared thermometry, enabling high-precision synchronous correlation analysis of electrical parameter changes, arc discharge processes, vegetation temperature rise, and ignition moments, providing strong data support for the study of electrical fire mechanisms.

[0034] 3. This invention integrates a temperature and humidity control system and a smoke exhaust device, which can simulate electrical fault tests under different environmental conditions and effectively handle the smoke generated during the test, ensuring the safety of the test environment. Attached Figure Description

[0035] Figure 1 The system structure block diagram of the comprehensive test platform for electrical fires on forest overhead power lines provided in the embodiments of the present invention.

[0036] Figure 2 This is a flowchart illustrating the comprehensive test method for electrical fires on overhead power lines in forests, provided in an embodiment of the present invention. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in further detail below with reference to the accompanying drawings and specific embodiments. However, it should be understood that the specific embodiments of this invention are only for explaining the invention and are not intended to limit the scope of protection of this invention.

[0038] Example 1:

[0039] This embodiment provides a comprehensive test platform for electrical fires on forest overhead power lines.

[0040] I. Overall Structure

[0041] like Figure 1 As shown, the comprehensive test platform for electrical fires on overhead power lines in forests in this embodiment includes: a high-voltage test unit 100, a low-voltage test unit 200, a power supply and distribution unit 300, a fault simulation and control unit 400, a data acquisition and waveform recording unit 500, an image acquisition unit 600, an environmental control unit 700, and a central control and protection unit 800.

[0042] The connections between the units are as follows:

[0043] The input terminal of the power supply and distribution unit 300 is connected to the external power grid, and its output terminal is electrically connected to the input terminals of the high voltage test unit 100 and the low voltage test unit 200, respectively, to provide test power supplies of different voltage levels.

[0044] The output terminals of the high-voltage test unit 100 and the low-voltage test unit 200 are respectively connected to the test leads in the fault simulation and control unit 400.

[0045] The control signal output terminal of the central control and protection unit 800 is communicatively connected to the control terminals of the power supply and distribution unit 300, the high voltage test unit 100, the low voltage test unit 200, the fault simulation and control unit 400, and the environmental control unit 700, respectively, for sending control commands.

[0046] The input terminals of the data acquisition and recording unit 500 are connected to the voltage and current sampling terminals of the high-voltage test unit 100 and the low-voltage test unit 200, respectively, and its output terminal is communicatively connected to the data input terminal of the central control and protection unit 800.

[0047] The output of the image acquisition unit 600 is communicatively connected to the data input of the central control and protection unit 800.

[0048] The actuator of the environmental control unit 700 is located in the test area, and its sensors are communicatively connected to the input terminal of the central control and protection unit 800.

[0049] II. Specific structure of each unit:

[0050] (1) High-voltage test unit 100:

[0051] The high-voltage test unit 100 is used to conduct electrical fault simulation tests at voltage levels of 35kV and 10kV. It includes:

[0052] The 35kV test area and the 10kV test area are set up in isolated test rooms.

[0053] Single-phase ground fault simulation module: Supports single-phase tree contact test, single-phase conductor drooping ground test, and single-phase flue gas grounding test.

[0054] Phase-to-phase short-circuit fault simulation module: Supports phase-to-phase tree short-circuit test.

[0055] Grounding resistance adjustment device: including an adjustable grounding resistance box, used to simulate different grounding conditions.

[0056] (2) Low-pressure test unit 200:

[0057] The low-voltage test unit 200 is used to conduct electrical fault simulation tests at a voltage level of 380V. It includes:

[0058] 380V test area.

[0059] Phase-to-phase metallic short-circuit test module: includes adjustable fault resistor, replaceable metal connecting piece, and replaceable circuit breaker.

[0060] Metal molten droplet ignition test device: used to collect and observe the process of short-circuit splashed metal molten droplets igniting vegetation.

[0061] (3) Power supply and distribution unit 300:

[0062] The power supply and distribution unit 300 includes:

[0063] The first three-phase power transformer: 1000kVA, 10kV / 0.4kV, Dyn11 connection, is used to power the low-voltage test unit.

[0064] Second and third phase power transformer: 1000kVA, 10kV / 10kV, YNd11 connection, used for power supply of 10kV high voltage test unit.

[0065] The third three-phase power transformer: 1000kVA, 35kV / 10kV, YNd11 connection, is used for power supply of the 35kV high-voltage test unit.

[0066] High-voltage switchgear group: including 10kV incoming / outgoing line cabinets (6 units, rated current 630A, rated short-circuit breaking current 25kA), 10kV PT cabinet (1 unit), 10kV capacitor cabinet (1 unit, 12kvar), 10kV reactor cabinet (1 unit, 6kvar), 35kV outgoing line cabinet (1 unit, rated current 630A, rated short-circuit breaking current 25kA), 35kV capacitor cabinet (1 unit, 200kvar), 35kV reactor cabinet (1 unit, 100kvar).

[0067] 380V low-voltage outgoing switchgear (1 unit, rated current 2000A, rated short-circuit breaking current 55kA).

[0068] Neutral point grounding mode adjustment device: including grounding switch group and replaceable arc suppression coil, which can switch between four modes: neutral point ungrounded, small current grounded, large current grounded, and grounded through arc suppression coil.

[0069] (4) Fault simulation and control unit 400:

[0070] The fault simulation and control unit 400 includes:

[0071] 1) Robotic arm tree control system:

[0072] The robotic arm tree control system includes: a base, a multi-degree-of-freedom articulated arm, a gripper, servo drive motors, displacement sensors, and a PID controller. The base is fixed to the ground in the test area. One end of the multi-degree-of-freedom articulated arm is connected to the base, and the other end is connected to the gripper. The gripper is used to hold the tree sample. The servo drive motors drive the movement of each joint of the multi-degree-of-freedom articulated arm. The displacement sensors detect the position of the gripper in real time. The PID controller receives feedback signals from the displacement sensors and controls the servo drive motors to achieve closed-loop control with a control accuracy of ±0.5cm.

[0073] Driven by a servo motor, the multi-degree-of-freedom articulated arm can achieve swinging motion with an adjustable swing amplitude of 0-60° and an adjustable swing frequency of 0-10Hz, which is used to simulate the swaying state of trees under natural wind.

[0074] 2) Conductor lifting and spacing adjustment mechanism:

[0075] The conductor lifting and spacing adjustment mechanism is used to automatically adjust test variables such as phase spacing, conductor height, distance between conductor and tree, and distance between conductor and ground.

[0076] (5) Data acquisition and waveform recording unit 500:

[0077] The data acquisition and waveform recording unit 500 includes the GDLB-2023 power fire accident waveform and analysis device, which has 32-96 analog input channels and 32-256 digital input channels, with sampling rates of 1K, 5K, and 10KHz selectable. This device can automatically record the changes in electrical quantities before and after the fault, and supports fault diagnosis, protection, and evaluation of switch action behavior.

[0078] (6) Image acquisition unit 600:

[0079] The image acquisition unit 600 includes:

[0080] High-speed camera system: It shoots at 120fps in 4K resolution, using a BIONZ XR image processor and an Exmor R CMOS sensor to capture the instantaneous process of discharge ignition.

[0081] Dual-spectrum monitoring system: Integrating visible light and thermal imaging sensors, with a temperature measurement range of -20℃ to 550℃ and a measurement accuracy of ±2℃. This system supports intelligent fire detection, abnormal temperature alarms, and smoke / fire detection functions.

[0082] (7) Environmental control unit 700:

[0083] The environmental control unit 700 includes:

[0084] Temperature and humidity control system: including air conditioning unit and humidification device, temperature adjustment range 10℃~55℃, humidity adjustment range 5%~95%.

[0085] Smoke exhaust device: including smoke detector, air valve, pressurized fan and smoke exhaust duct. During or after the test, when the smoke detector detects that the smoke concentration exceeds the set value, the pressurized fan will be automatically started to exhaust the smoke through the air valve and smoke exhaust duct.

[0086] (8) Central Control and Protection Unit 800:

[0087] The central control and protection unit 800 includes:

[0088] Multifunctional control console: It has manual control mode and automatic control mode, and can control the closing and opening of the switch cabinet, control the conductor lifting and spacing adjustment mechanism 420 and the robotic arm tree control system 410. It is equipped with a large screen to display multiple monitoring screens at the same time.

[0089] Centralized control software: used to monitor the voltage and current signal waveforms and alarm information of each phase and neutral point in real time, record, display and print test data, and has event log query function.

[0090] The safety protection subsystem includes a local control switch, a remote control module, an emergency manual power cut-off button, a grounding rod discharge device, an audible and visual alarm, and a multi-stage circuit breaker group. This subsystem connects to the controller of the central control and protection unit 800. When an abnormal situation is detected (such as overcurrent, overvoltage, equipment failure, or unauthorized personnel entry), it can automatically or manually cut off the power supply. The test platform is designed to withstand a maximum fault current of no more than 60A for a duration of no more than 10 seconds.

[0091] Example 2:

[0092] This embodiment provides a comprehensive test method for electrical fires on forest overhead power lines, applied to the platform described in Embodiment 1. For example... Figure 2 As shown, the method includes the following steps:

[0093] Step S1: Parameter settings:

[0094] Test requirements are set through the central control and protection unit, including selecting voltage level, fault type, and ambient temperature and humidity.

[0095] Operators set test parameters on the multi-functional control console 810 using the centralized control software 820. For example, they select a voltage level of 10kV, a fault type of single-phase tree contact test, a target temperature of 25℃, and a target humidity of 60%.

[0096] Step S2: Environmental adjustment:

[0097] The environmental control unit adjusts the temperature and humidity of the test area to the set values.

[0098] The central control and protection unit 800 sends instructions to the temperature and humidity control system to adjust the temperature and humidity of the test area to the set values ​​(25℃, 60%). After the temperature and humidity stabilize, the system indicates that it is ready.

[0099] Step S3: Position Adjustment

[0100] The fault simulation and control unit adjusts the conductor height, phase spacing, and the relative positions of trees and conductors.

[0101] The central control and protection unit 800 sends instructions to the conductor lifting and spacing adjustment mechanism 420 to adjust the conductor height to a set value (e.g., 5m from the ground) and the phase spacing to a set value (e.g., 0.5m). At the same time, it sends instructions to the robotic arm tree control system to move the tree sample to a predetermined position (e.g., 0.1m from the conductor).

[0102] Step S4: Power supply:

[0103] The central control and protection unit controls the power supply and distribution unit to supply power to the high-voltage test unit or the low-voltage test unit.

[0104] After confirming that all parameters are correct on the multi-function control panel 810, the operator clicks the "Ready" button. The central control and protection unit 800 controls the power supply and distribution unit 300 to close, supplying power to the high-voltage test unit 100.

[0105] Step S5: Fault Simulation

[0106] A fault simulation test was conducted by controlling the tree to contact the wire through the robotic arm tree control system, triggering a single-phase grounding or phase-to-phase short-circuit fault.

[0107] During the fault simulation test, the tree control system of the robotic arm simulates the swaying of trees under the action of wind. The swaying amplitude and swaying frequency are set according to the test requirements to study the characteristics of faults caused by dynamic contact between the conductor and the tree under different wind conditions.

[0108] The central control and protection unit 800 sends an "execute" command to the robotic arm tree control system 410. The robotic arm tree control system 410 begins to swing at a preset swing amplitude (e.g., 30°) and swing frequency (e.g., 2Hz), causing the tree sample to come into dynamic contact with the live wire, triggering a single-phase ground fault.

[0109] Step S6: Data Acquisition

[0110] The data acquisition and waveform recording unit collects voltage and current waveforms during the fault process in real time, while the image acquisition unit simultaneously collects visible light images and infrared thermal images of the fault process.

[0111] At the moment the fault occurs, the data acquisition and recording unit 500 begins acquiring and recording voltage and current waveforms before and after the fault at a sampling rate of 10kHz. Simultaneously, the high-speed camera system 610 captures visible light images of the fault process at 120fps, while the dual-spectrum monitoring system 620 simultaneously captures infrared thermal images, recording changes in vegetation surface temperature and the ignition process. All data is transmitted to the data storage module of the central control and protection unit 800.

[0112] Step S7: End of experiment:

[0113] The central control and protection unit automatically cuts off the power supply and ends the test upon detecting a fault or vegetation ignition.

[0114] When the centralized control software 820 detects relay protection activation or vegetation ignition, it automatically sends a trip command to the power supply and distribution unit 300 to cut off the power. Operators can also press the emergency manual power cut-off button to end the test, depending on the site conditions.

[0115] Step S8: Smoke extraction:

[0116] The smoke in the test area is removed by the smoke extraction device.

[0117] After the test, the smoke exhaust device automatically starts, the smoke detector detects the smoke concentration, controls the opening of the air valve and the speed of the pressurized fan to exhaust the smoke from the test area.

[0118] Example 3:

[0119] This embodiment is basically the same as Embodiment 2, except that step S5 performs a 380V phase-to-phase metallic short-circuit test. Specifically, it includes:

[0120] In step S3, there is no need to adjust the height of the guide wire and the position of the tree.

[0121] In step S5, a phase-to-phase metallic short circuit is directly performed through the low-voltage test unit 200. Different fault circuit resistances can be set, different metal connecting pieces and circuit breakers can be replaced, and the situation of the short-circuit splashed metal beads igniting the vegetation below can be observed.

[0122] Example 4:

[0123] This embodiment is basically the same as Embodiment 2, except that the fault type selected in step S1 is "single-phase flue gas grounding test". Specifically, it includes:

[0124] In step S3, there is no need to adjust the position of the trees.

[0125] In step S5, the vegetation or combustibles in the test area are first ignited using an external ignition device to generate smoke. Then, the single-phase conductor is moved to the smoke area by the robotic arm tree control system 410 to observe the continuity between the conductor and the grounding conductor through the smoke, and to monitor the composition and concentration of the smoke.

[0126] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A forest overhead line electrical fire comprehensive test platform, characterized in that, include: High voltage test unit (100), low voltage test unit (200), power supply and distribution unit (300), fault simulation and control unit (400), data acquisition and waveform recording unit (500), image acquisition unit (600), environmental control unit (700) and central control and protection unit (800). High voltage test unit (100): used to conduct electrical fault simulation tests at voltage levels of 35kV and 10kV, including single-phase ground fault test and phase-to-phase short circuit fault test, wherein the single-phase ground fault test includes single-phase tree contact test, single-phase conductor drooping ground test and single-phase flue gas grounding test; Low-voltage test unit (200): used to conduct electrical fault simulation tests at a voltage level of 380V, including phase-to-phase metallic short-circuit tests; The output terminals of the high-voltage test unit (100) and the low-voltage test unit (200) are respectively connected to the test leads in the fault simulation and control unit (400); Power supply and distribution unit: including multi-voltage level transformer group and switch cabinet group, used to provide test power supply with different voltage levels and different neutral point grounding methods for the high voltage test unit (100) and low voltage test unit (200); Fault simulation and control unit (400): includes a robotic arm tree control system and a wire lifting and spacing adjustment mechanism, used to automatically control variable parameters during the test process and simulate electrical faults under different working conditions. The robotic arm tree control system adopts PID closed-loop control to control the contact state between the tree and the wire and simulate the swaying of the tree under the action of wind. Data acquisition and recording unit (500): includes a multi-channel recording device and a waveform analysis system, used to acquire, record and analyze voltage and current waveforms and electrical parameters during the test in real time; the input terminal of the data acquisition and recording unit (500) is connected to the voltage and current sampling terminals of the high voltage test unit (100) and the low voltage test unit (200) respectively, and its output terminal is connected to the data input terminal of the central control and protection unit (800) in communication. Image acquisition unit (600): includes a high-speed camera system and a dual-spectrum monitoring system, used to capture visible light and infrared images of electrical fault occurrence, arc breakdown and vegetation ignition process; the output end of the image acquisition unit (600) is communicatively connected to the data input end of the central control and protection unit (800); Environmental control unit: including temperature and humidity control system and smoke exhaust device, used to regulate the temperature and humidity of the test environment and remove smoke produced by combustion; Its sensors are communicatively connected to the input of the central control and protection unit (800); Central control and protection unit (800): includes a multi-functional console and centralized control software, used to centrally monitor the operating status of each unit, remotely control the test process, and has multiple safety protection functions; the control signal output terminal of the central control and protection unit (800) is connected to the control terminals of the power supply and distribution unit (300), high voltage test unit (100), low voltage test unit (200), fault simulation and control unit (400), and environmental control unit (700) respectively, and is used to send control commands.

2. The forest overhead line electrical fire comprehensive test platform according to claim 1, characterized in that, The high-voltage test unit supports the following single-phase ground fault test modes: Single-phase tree contact test: The robotic arm tree control system controls the tree to contact the live wire, simulating a single-phase wire grounding fault through the tree. It supports changing the tree type, changing the wire specification, adjusting the wire height, and adjusting the distance between the tree and the wire. Single-phase conductor drop ground test: simulates the dynamic process of a conductor dropping through shrubs, leaves or soil after a single-phase wire break, causing a ground fault. It supports changing the grounding vegetation type and adjusting the distance between the conductor and the ground. Single-phase flue gas grounding test: simulates a fault in which a single-phase conductor is connected to a grounding conductor by flue gas generated during combustion, supporting the monitoring of flue gas composition and concentration; In the single-phase ground fault test, the grounding resistance can be adjusted.

3. The forest overhead line electrical fire comprehensive test platform according to claim 1, characterized in that, The high-voltage test unit supports phase-to-phase tree short-circuit tests, simulating a fault where two phase conductors short-circuit through a tree. It also supports switching voltage levels, changing tree types, changing conductor specifications, adjusting the phase spacing, and adjusting the distance between the tree and the conductor.

4. The forest overhead line electrical fire comprehensive test platform according to claim 1, characterized in that, The power supply and distribution unit supports adjustment of the neutral point grounding method, including neutral point ungrounded, low current grounded, high current grounded, and grounded through an arc suppression coil. The arc suppression coil can be replaced with different specifications.

5. The forest overhead line electrical fire comprehensive test platform according to claim 1, characterized in that, The low-voltage test unit supports phase-to-phase metallic short-circuit testing, can adjust the resistance of the fault circuit, can change the type of connection metal, can change the circuit breaker specifications, and can conduct tests on the ignition of vegetation by metal droplets splashed during short circuits.

6. The forest overhead line electrical fire comprehensive test platform according to claim 1, characterized in that, The fault simulation and control unit includes: The robotic arm tree control system adopts PID closed-loop control with a control accuracy of ±0.5cm. The swing amplitude is adjustable from 0 to 60° and the swing frequency is adjustable from 0 to 10Hz. It is used to simulate the swaying state of trees under natural wind force and trigger changes in the distance between the trees and high-voltage lines. Conductor lifting and spacing adjustment mechanism: used to automatically adjust phase spacing, conductor height, distance between conductor and trees, and distance between conductor and ground.

7. The forest overhead line electrical fire comprehensive test platform according to claim 1, characterized in that, The environmental control unit includes: Temperature and humidity control system, with a temperature adjustment range of 10℃~55℃ and a humidity adjustment range of 5%~95%; The smoke exhaust device, including a smoke detector, a damper, and a pressurized fan, is used to remove the smoke generated during or after the test.

8. The comprehensive test platform for electrical fires on forest overhead power lines according to claim 1, characterized in that, The central control and protection unit includes: Multifunctional control console: It has manual control mode and automatic control mode, can control the closing and opening of switch cabinet, control the lifting and spacing adjustment mechanism of conductor, and is equipped with a large screen to display multiple monitoring screens at the same time; Centralized control software: used to monitor the voltage and current signal waveforms and alarm information of each phase and neutral point in real time, record, display and print test data, and has event log query function; Safety protection subsystem: includes local and remote control test circuit switching function, emergency manual power cut-off function, grounding rod discharge device, audible and visual hazard warning system, and multi-level switch control and protection function.

9. A comprehensive test method for electrical fires on forest overhead power lines, applied to the comprehensive test platform for electrical fires on forest overhead power lines as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Step S1: According to the test requirements, set the test parameters through the central control and protection unit, including selecting the voltage level, fault type, and ambient temperature and humidity; Step S2: Adjust the temperature and humidity of the test area to the set values ​​using the environmental control unit; Step S3: Adjust the conductor height, phase spacing, and relative position of trees and conductors through the fault simulation and control unit; Step S4: The central control and protection unit controls the power supply and distribution unit to supply power to the high-voltage test unit or the low-voltage test unit; Step S5: Perform a fault simulation test by controlling the tree to contact the wire through the robotic arm tree control system to trigger a single-phase grounding or phase-to-phase short circuit fault; Step S6: The voltage and current waveforms during the fault process are acquired in real time through the data acquisition and waveform recording unit, and the visible light image and infrared thermal image of the fault process are acquired synchronously through the image acquisition unit. Step S7: Upon detecting a fault or vegetation ignition, the central control and protection unit automatically cuts off the power supply, thus ending the test. Step S8: Remove the smoke from the test area using the smoke extraction device.

10. The comprehensive test method for electrical fires on forest overhead power lines according to claim 9, characterized in that, In step S5, when performing the fault simulation test, the tree control system of the robotic arm simulates the swaying of trees under the action of wind. The swaying amplitude and swaying frequency are set according to the test requirements to study the characteristics of faults caused by dynamic contact between the conductor and the tree under different wind conditions.

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