Insulation material breakdown testing device and testing method based on force-electric synchronous measurement

Abstract

The application discloses an insulation material breakdown testing device and method based on force-electric synchronous measurement, and the device comprises a support rack, and mechanical puncture units, high-voltage electrical units, signal acquisition and control units and sample grounding units are arranged on the support rack respectively. The method comprises the following steps: fixing the insulation material to be tested, setting test parameters, starting dynamic puncture and synchronously applying high voltage, synchronously collecting puncture force, displacement, applied voltage, leakage current and partial discharge signals, determining the insulation failure critical point through a multi-physical quantity fusion criterion, identifying the failure mode, and finally outputting quantitative characteristic parameters and a test report. The application can realize microsecond-level synchronous force-electric-displacement collection. The application can be widely applied to the technical field of high-voltage insulation testing.

Description

Technical Field

[0001] This invention relates to the field of high-voltage insulation testing technology, and in particular to an insulation material breakdown testing device and method based on force-electric synchronous measurement. Background Technology

[0002] In high-voltage electrical equipment, new energy vehicle drive motors, aviation electrical interconnection systems, and high-end electronic packaging, soft insulating materials (such as polyimide films, epoxy coatings, and silicone rubber insulating layers) are widely used for conductor surface coating or interlayer isolation. During manufacturing, assembly, and operation, these materials may be subjected to dynamic puncture from sharp objects such as metal burrs, screw sharp edges, and conductive particles, and may experience insulation failure under high-voltage conditions.

[0003] Existing insulation material testing technologies are mainly divided into two categories: 1) Static high-voltage breakdown test: This method involves placing electrodes on both sides or the surface of the material without mechanical stress, slowly increasing the voltage until breakdown occurs, and recording the breakdown voltage. Its limitation is that it assesses the intrinsic breakdown strength of "intact, undamaged" insulation materials, and cannot simulate the composite stress scenario in actual engineering where "mechanical damage occurs first, followed by electrical failure." Numerous engineering failure cases show that insulation failure often originates from minor mechanical damage (such as scratches, indentations, and punctures) generated during manufacturing or assembly, which cannot be induced or evaluated in static testing.

[0004] 2) Mechanical puncture strength test: This type of method only focuses on the mechanical properties of the material to resist mechanical puncture (such as maximum puncture force and penetration displacement), without applying high voltage. Therefore, it cannot answer the core engineering question of "to what extent mechanical damage will lead to insulation failure", nor can it provide quantitative data on electrical safety margin. Summary of the Invention

[0005] To address the aforementioned technical problems, the purpose of this invention is to provide an insulating material breakdown test device and method based on force-electric synchronous measurement, which can achieve microsecond-level synchronous force-electric-displacement acquisition.

[0006] The first technical solution adopted in this invention is: an insulation material breakdown testing device based on force-electric synchronous measurement, comprising a support frame, on which a mechanical puncture unit, a high-voltage electrical unit, a signal acquisition and control unit, and a sample grounding unit are respectively arranged, wherein: The mechanical puncture unit includes a servo drive module, a force sensor, a displacement sensor, and a puncture probe. The servo drive module is vertically mounted on the upper part of the support frame. The force sensor is fixed to the moving output end of the servo drive module. The puncture probe is coaxially connected to the lower end of the force sensor. The displacement sensor is set to detect the vertical displacement of the puncture probe. The high-voltage electrical unit includes a programmable high-voltage source, a high-voltage probe, and a current detection module. The high-voltage output terminal of the programmable high-voltage source is electrically connected to the puncture probe. The high-voltage probe is connected in parallel in the high-voltage output circuit, and the current detection module is connected in series in the system grounding circuit. The signal acquisition and control unit includes a multi-channel synchronous data acquisition system, an industrial computer, and a synchronous control module. The multi-channel synchronous data acquisition system is connected to the force sensor, displacement sensor, high-voltage probe, and current detection module respectively. The synchronous control module is connected to the servo drive module, programmable high-voltage source, and trigger of the multi-channel synchronous data acquisition system respectively. The industrial computer is communicatively connected to the multi-channel synchronous data acquisition system and the synchronous control module. The sample grounding unit includes a grounding platform and a sample clamp. The grounding platform is located directly below the puncture probe and is electrically connected to the system grounding terminal. The sample clamp is used to fix the insulating material to be tested onto the surface of the grounding platform.

[0007] Furthermore, the support frame adopts a double-column adjustable crossbeam structure, with two support columns vertically fixed on the base. The crossbeam structure is slidably connected to the support columns via a slider for height adjustment. The servo drive module is installed on the crossbeam via a horizontal adjustment component for horizontal position adjustment.

[0008] Furthermore, the servo drive module includes a servo motor, a ball screw, and a slide table. The servo motor drives the slide table to perform vertical reciprocating motion through the ball screw. The lower end of the slide table is fixedly connected to a displacement sensor. The displacement sensor includes a grating ruler and a grating reading head. The grating ruler is fixed on the load mounting plate, and the grating reading head is fixed to the side of the slide table.

[0009] Furthermore, the programmable high-voltage source is an AC / DC switchable high-voltage source with a built-in hardware overcurrent protection module, and the control interface of the programmable high-voltage source supports analog control and digital communication connection.

[0010] Furthermore, the current detection module includes a high-frequency current transformer and a low-frequency current transformer. The high-frequency current transformer and the low-frequency current transformer are connected in parallel in the grounding circuit. The high-frequency current transformer is used to detect partial discharge signals, and the low-frequency current transformer is used to detect power frequency leakage current.

[0011] Furthermore, the multi-channel synchronous data acquisition system includes a high-speed acquisition channel and a low-speed acquisition channel. The high-speed acquisition channel is connected to the high-frequency current transformer signal, and the low-speed acquisition channel is connected to the force sensor, displacement sensor, high-voltage probe, and low-frequency current transformer signal respectively. The high-speed acquisition channel and the low-speed acquisition channel are synchronized through a unified system clock source.

[0012] Furthermore, the synchronization control module outputs a unified hardware trigger signal, which is distributed to the start-up terminal of the servo drive module, the output control terminal of the programmable high-voltage source, and the external trigger terminal of the multi-channel synchronous data acquisition system.

[0013] Furthermore, it also includes a transparent insulating protective cover that covers the high-voltage test area. The transparent insulating protective cover is equipped with a door lock interlock switch, which is connected in series with the control circuit of the programmable high-voltage source and automatically cuts off the high-voltage output when the door is opened.

[0014] Furthermore, electromagnetic shielding plates are respectively installed on both sides of the support frame, and the electromagnetic shielding plates correspond to the installation positions of the high-voltage power supply and the industrial control computer. The system operation panel of the electromagnetic shielding plate is equipped with an emergency stop button, which is connected in series in the power supply circuit of the servo drive module and the programmable high-voltage source.

[0015] The second technical solution adopted in this invention is: a test method for an insulating material breakdown test device based on force-electric synchronous measurement, comprising the following steps: The insulating material to be tested is fixed on the grounding platform. The puncture speed, high voltage output value, failure judgment threshold and acquisition parameters are set by the industrial control computer, and the system self-test is executed. After the self-test is passed, the test program is started. The servo drive module drives the puncture probe to move downward at a set speed. When the force sensor detects that the contact force exceeds the set threshold, the synchronous control module triggers the programmable high voltage source to output the set voltage, and at the same time triggers the multi-channel synchronous data acquisition system to synchronously record the puncture displacement, puncture force, applied voltage, leakage current and partial discharge signal. Based on synchronously acquired multi-channel data, the critical point of insulation failure is determined by fusing leakage current mutation criteria, partial discharge initiation criteria, and force-displacement penetration characteristic criteria, and the displacement, force value, and time parameters at the corresponding time are recorded. Based on the recorded data, and according to the timing relationship and waveform characteristics of the force and electrical signals, the system automatically identifies the failure modes and generates a test report containing test curves and failure characteristic parameters.

[0016] The beneficial effects of the method and apparatus of this invention are as follows: This invention is based entirely on electrical and mechanical signals, and is applicable to all soft insulating materials, including opaque coatings, films, rubber, etc. Furthermore, it achieves automatic and objective insulation failure determination through threshold and slope methods, eliminates human visual errors, and designs and realizes microsecond-level synchronous force-electricity-displacement acquisition, providing data support for the study of insulation failure mechanisms. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the insulation material breakdown test device based on force-electric synchronous measurement of the present invention; Figure 2 This is a schematic diagram of the test method of the insulation material breakdown test device based on force-electric synchronous measurement of the present invention; Figure 3 This is a schematic diagram of the device connections for the insulation material breakdown test device provided in a specific embodiment of the present invention; Figure 4 This is a three-dimensional structural schematic diagram of the insulation material breakdown test device provided in a specific embodiment of the present invention.

[0018] Reference numerals: 1. Probe mounting block; 2. Puncture probe; 3. Insulating base plate; 4. Sample stage; 5. Grounding copper plate; 6. Probe mounting plate; 7. Sensor bracket; 8. Grating displacement sensor; 9. Grating ruler; 10. Support column; 11. Slide table surface; 12. Rib plate; 13. L-shaped connecting plate; 14. Load mounting plate; 15. Horizontal adjustment plate; 16. Servo drive module; 17. Force sensor; 18. Rear cover; 19. U-shaped plate; 20. Flange sleeve; 21. Ceramic connecting rod. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only for ease of explanation and do not limit the order of the steps. The execution order of each step in the embodiments can be adapted according to the understanding of those skilled in the art.

[0020] First, it should be noted that this invention aims to overcome the dual shortcomings of existing insulation material testing technologies—namely, that "static high-voltage testing cannot simulate mechanical damage" and "mechanical puncture testing lacks electrical evaluation"—by providing a dynamic puncture testing system and method based on simultaneous force-electrical measurement. Its specific objectives include: 1) Simulate the failure chain of real engineering: Apply high voltage synchronously during dynamic puncture to restore the complete physical process of mechanical damage-electric field distortion-insulation failure, so that the test results are closer to the actual working conditions.

[0021] 2) Achieve quantitative and automated judgment of insulation failure: Synchronously collect puncture displacement, puncture force, leakage current and partial discharge signals, establish insulation failure criteria based on the fusion of multiple physical quantities (including leakage current mutation, partial discharge initiation, force-displacement penetration point timing alignment), eliminate human judgment error, and output quantitative parameters (such as insulation failure critical displacement, degradation initiation displacement, force-electrical hysteresis time, etc.).

[0022] 3) Supports failure mode identification and mechanism analysis: Based on the time correlation and waveform characteristics of force-electric signals, it automatically distinguishes typical failure modes such as instantaneous breakdown, progressive degradation, and mechanically dominated failure, providing data support for material optimization, process improvement and fault analysis.

[0023] Reference Figure 1 and Figure 3 This invention provides an insulation material breakdown testing device based on force-electric synchronous measurement, including a support frame. The support frame is equipped with a mechanical puncture unit, a high-voltage electrical unit, a signal acquisition and control unit, and a sample grounding unit. The support frame adopts a double-column adjustable crossbeam structure, with two support columns vertically fixed to a base. The crossbeam structure is height-adjustable via a slider connected to the support columns. A servo drive module is mounted on the crossbeam for horizontal position adjustment via a horizontal adjustment component. The mechanical puncture unit includes a servo drive module, a force sensor, a displacement sensor, and a puncture probe. The servo drive module is vertically mounted on the upper part of the support frame. The force sensor is fixed to the moving output end of the servo drive module. The puncture probe is coaxially connected to the lower end of the force sensor. The displacement sensor is set to detect the vertical displacement of the puncture probe. Specifically, the servo drive module includes a servo motor, a ball screw, and a slide table. The servo motor drives the slide table to perform vertical reciprocating motion through the ball screw. The lower end of the slide table is fixedly connected to a displacement sensor. The displacement sensor includes a grating ruler and a grating reading head. The grating ruler is fixed on the load mounting plate, and the grating reading head is fixed to the side of the slide table.

[0024] In this embodiment, the mechanical puncture unit specifically includes a base and support structure, a servo drive module, a force sensor, a displacement sensor, and a probe assembly.

[0025] Base and support structure: The high-strength aluminum alloy frame with anodized surface provides a stable installation foundation.

[0026] Servo Drive Module: Servo motor drive module: Mounted on a vertical bracket, it drives the moving platform via a high-precision ball screw (C3 grade or higher, recommended lead 2-5 mm) to achieve displacement control or force control. Movement speed range: 0.1~100 mm / min; positioning accuracy: ≤±0.01 mm; feedback is achieved through a fully closed-loop optical encoder. Using a servo motor with a rated torque of not less than 1.27 N·m (400W class), coupled with a 2 mm lead ball screw, it can output a theoretical thrust exceeding 2000 N, sufficient to meet the puncture requirements of various insulating materials, and ensuring stability and control accuracy during low-force testing.

[0027] Force sensor: fixed to the end of the probe assembly, measuring range 0–3 kN, accuracy ±0.1% FS, outputting an analog voltage signal.

[0028] Displacement sensor: A high-precision optical grating ruler or laser displacement sensor is used, which is installed between the slide table and the load mounting plate to directly measure the vertical displacement of the probe with a resolution of ≤1μm.

[0029] Probe assembly: Replaceable metal probes are available in three types with tip radii of 0.1mm, 0.3mm, and 0.5mm. Probes with different parameters can also be customized to meet specific requirements. The probes are made of tungsten carbide or cemented carbide and connect to the lower end of the force sensor via threads.

[0030] like Figure 4 As shown, the test platform uses a double-column supported adjustable beam structure as its main frame, which is installed on the insulating base plate 3. Tracks and sliders are installed on the sides of the support columns 10, and the vertical height adjustment of the entire puncture assembly is controlled by connecting plates to the beam. The adjustable beam is connected to the load mounting plate 14 via a horizontal adjustment plate 15, an L-shaped connecting plate 13, and a pair of reinforcing ribs 12, to control the horizontal position adjustment of the entire puncture device. The servo drive module 16 is vertically installed on the load mounting plate 14. The probe assembly is assembled and fixed via a U-shaped plate 19 and then combined with the probe mounting plate 6 and installed on the slide table 11. The puncture action is completed under the drive of the servo drive module 16. The grating displacement sensor 8 is installed on the side of the slide table 11 via a sensor bracket 7, and a grating ruler 9 is installed at the corresponding position on the load mounting plate 14. The two work together to complete the real-time monitoring and recording of displacement during the puncture process. Force sensor 17 is connected to rear cover 18, and rear cover 18 is connected to flange sleeve 20 via U-shaped plate 19. The three are connected by the same set of bolts and nuts to ensure coaxiality. Puncture probe 2 is mounted on probe mounting block 1. Ceramic connecting rod 21 directly connects the entire rear cover 18 and flange sleeve 20, rigidly connecting probe mounting block 1 and force sensor 17 to ensure real-time measurement of puncture force during puncture. Grounding copper plate 5 is installed at the center of insulating base plate 3 to ensure a stable and safe testing environment. Sample stage 4 is mounted above grounding copper plate 5.

[0031] The high-voltage electrical unit includes a programmable high-voltage source, a high-voltage probe, and a current detection module. The high-voltage output terminal of the programmable high-voltage source is electrically connected to the puncture probe. The high-voltage probe is connected in parallel in the high-voltage output circuit, and the current detection module is connected in series in the system grounding circuit. Specifically, the programmable high-voltage source is an AC / DC switchable high-voltage source with a built-in hardware overcurrent protection module, and the control interface of the programmable high-voltage source supports analog control and digital communication connection.

[0032] The current detection module includes a high-frequency current transformer and a low-frequency current transformer. The high-frequency current transformer and the low-frequency current transformer are connected in parallel in the grounding circuit. The high-frequency current transformer is used to detect partial discharge signals, and the low-frequency current transformer is used to detect power frequency leakage current.

[0033] In this embodiment, the high-voltage electrical unit includes a programmable high-voltage source, a high-voltage probe, and a current detection module.

[0034] The programmable high-voltage source utilizes an AC / DC switchable high-voltage source module with an continuously adjustable output voltage of 0–10 kV. It features fast hardware overcurrent protection (response time ≤ 1 ms), as well as short-circuit withstand, arcing protection, and overvoltage / overtemperature protection, capable of withstanding frequent discharge conditions. Output ripple is ≤ 0.01% pp, and stability is ≤ 0.01% / 8h. The control interface supports analog control (0–10 V / 0–5 V) and digital communication (RS-485 / Modbus) for connection to the main control system, and supports external trigger signals to control the start and stop of the high-voltage output.

[0035] High-voltage probe: Installed in the high-voltage output circuit, it adopts a high-voltage differential probe with a bandwidth ≥100 MHz, attenuation ratio 1000:1, and rise time ≤3.5 ns. It is used to monitor the actual applied voltage waveform, attenuating the 0-10 kV high voltage to a ±10 V low-voltage analog signal. The output impedance is 50Ω, and it is connected to the high-speed acquisition channel via a BNC interface.

[0036] Current detection module: Utilizing an HFCT + low-frequency current transformer combination, it is mounted in the grounding loop. The HFCT monitors partial discharge signals, with a detection bandwidth of 100 kHz–50 MHz, transmission impedance ≥5 mV / mA, detection sensitivity ≤5 pC, and output impedance of 50Ω. It connects to the high-speed acquisition channel via a BNC interface. The sensor employs a fully metal shielded structure, providing resistance to external electromagnetic interference. For power frequency leakage current, a low-frequency current transformer (such as a Rogowski coil) is connected in parallel, and its output signal is connected to the low-speed acquisition channel.

[0037] The signal acquisition and control unit includes a multi-channel synchronous data acquisition system, an industrial computer, and a synchronous control module. The multi-channel synchronous data acquisition system is connected to the force sensor, displacement sensor, high-voltage probe, and current detection module respectively. The synchronous control module is connected to the servo drive module, programmable high-voltage source, and trigger of the multi-channel synchronous data acquisition system respectively. The industrial computer is communicatively connected to the multi-channel synchronous data acquisition system and the synchronous control module. Specifically, the multi-channel synchronous data acquisition system includes a high-speed acquisition channel and a low-speed acquisition channel. The high-speed acquisition channel is connected to a high-frequency current transformer signal, and the low-speed acquisition channel is connected to a force sensor, a displacement sensor, a high-voltage probe, and a low-frequency current transformer signal, respectively. The high-speed acquisition channel and the low-speed acquisition channel are synchronized through a unified system clock source.

[0038] The synchronization control module outputs a unified hardware trigger signal, which is distributed to the start-up terminal of the servo drive module, the output control terminal of the programmable high-voltage source, and the external trigger terminal of the multi-channel synchronous data acquisition system.

[0039] In this embodiment, the signal acquisition and control unit includes a multi-channel synchronous data acquisition system and a synchronous control and triggering system. The multi-channel synchronous data acquisition system includes a high-speed acquisition channel, a low-speed acquisition channel, a synchronization mechanism, and an industrial control computer.

[0040] For high-speed acquisition channels: used for partial discharge signal acquisition, with a sampling rate ≥100 MS / s and an analog bandwidth ≥50MHz.

[0041] For low-speed acquisition channels: used for acquiring slowly changing signals such as force, displacement, and voltage (RMS), with a sampling rate ≥100kS / s.

[0042] Regarding the synchronization mechanism: High-speed and low-speed acquisition cards are installed in the same PXI / PXIe chassis, and inter-board synchronization is achieved through the backplane clock bus or an external reference clock to ensure that all channels align the sampled data under the same time base. The sampling clock synchronization error between channels within the acquisition system is ≤1μs.

[0043] For industrial PCs: Installed in the electrical control cabinet, they run host computer software to achieve parameter setting, data recording, real-time waveform display, and automatic judgment functions. The industrial PC connects to the acquisition system via PXIe / PCIe bus to complete high-speed data throughput and real-time processing.

[0044] For synchronous control and triggering systems, the specific components include: Hardware trigger synchronization: A unified hardware trigger signal is generated by the synchronization control module and synchronously distributed to the servo motor driver start input terminal, the high voltage power supply output control terminal, and the external trigger input terminal of the acquisition card to ensure the electrical synchronization accuracy of event triggering.

[0045] Synchronization accuracy definition: The electrical time difference between the output of the trigger signal from the synchronization control module and the receipt of the effective trigger edge by each subsystem is ≤1 μs.

[0046] Clock synchronization architecture: A unified system clock source is used to provide a common time base for the acquisition system, motion controller and trigger module, avoiding long-term synchronization drift caused by independent clocks of each subsystem.

[0047] High-voltage safety interlock and delay compensation: Electrical isolation devices and safety interlock circuits must be configured between the synchronous control module and the high-voltage power supply; during system integration, the rise / fall time delay of the high-voltage power supply response should be measured and compensated to ensure that the actual applied high voltage and the acquisition and recording window strictly correspond in physical time.

[0048] Servo motion synchronization explanation: The mechanical motion response of the servo motor after receiving the trigger signal has an inherent inertial delay. Its mechanical motion start time lags behind the trigger signal. This is a normal response characteristic of the servo system and is not used as a synchronization accuracy assessment indicator.

[0049] External trigger input and synchronization clock: All acquisition channels have independent external trigger input ports and synchronous clock interfaces, supporting pre / post trigger modes and adjustable trigger delay, facilitating accurate event alignment acquisition under a unified triggering system.

[0050] Overall time synchronization error requirements: Under a unified clock source and hardware triggering architecture, the electrical edge arrival time error of the trigger event from the synchronization module to each subsystem (acquisition card, servo driver enable, high-voltage output control) is ≤1 μs. After system integration, this synchronization accuracy must be verified by actual measurement using an oscilloscope or time interval measuring instrument.

[0051] The sample grounding unit includes a grounding platform and a sample clamp, with the grounding platform positioned directly below the puncture probe.

[0052] The grounding platform is electrically connected to the system grounding terminal, and the sample clamp is used to fix the insulating material to be tested onto the surface of the grounding platform.

[0053] The sample fixing and grounding unit includes: Grounding platform: Made of copper plate with a flat surface, it is connected to the system grounding busbar through copper braided tape to ensure low impedance grounding.

[0054] Sample clamps: The clamps and fixing screws are made of insulating materials (such as polytetrafluoroethylene) to ensure that the sample does not slip during the puncture process and does not interfere with the electric field distribution.

[0055] Furthermore, the embodiments of the present invention also include a transparent insulating protective cover, which covers the high-voltage test area. The transparent insulating protective cover is equipped with a door lock interlock switch, which is connected in series with the control circuit of the programmable high-voltage source and automatically cuts off the high-voltage output when the door is opened.

[0056] Electromagnetic shielding plates are respectively installed on both sides of the support frame. The electromagnetic shielding plates correspond to the installation positions of the high-voltage power supply and the industrial control computer. The system operation panel of the electromagnetic shielding plate is equipped with an emergency stop button, which is connected in series in the power supply circuit of the servo drive module and the programmable high-voltage source.

[0057] For safety protection structures, including: Transparent insulating protective cover: Made of polycarbonate material, it covers the high-voltage area and is equipped with a door lock interlock switch that automatically cuts off the high-voltage output when the door is opened.

[0058] Electromagnetic shielding: Electromagnetic shielding plates were added to both sides of the high-voltage power supply and the industrial control computer to minimize interference to various sensitive devices and data during high-voltage testing.

[0059] Emergency stop button: Located on the control panel and remotely, pressing it immediately cuts off the motor power and high voltage output.

[0060] In summary, compared with the prior art, the embodiments of the present invention have the following advantages: 1) Not dependent on material transparency: Based entirely on electrical and mechanical signals, it is applicable to all soft insulating materials, including opaque coatings, films, rubber, etc.

[0061] 2) Quantitative judgment: Automatic and objective insulation failure judgment is achieved through threshold method and slope method, eliminating human visual error.

[0062] 3) Multi-physics synchronization: Design and realize microsecond-level synchronized force-electric-displacement acquisition to provide data support for the study of insulation failure mechanism.

[0063] 4) Strong instrument compliance: All sensors and high-voltage equipment are selected and laid out according to standards to meet the safety and accuracy requirements of high-voltage testing.

[0064] 5) Simple structure: No optical system required, low system complexity, high reliability, and easy maintenance.

[0065] 6) Design is feasible: All structural components use standard parts or custom-made parts, the assembly relationship is clear, and it can be reproduced based on the three-dimensional structural diagram.

[0066] Reference Figure 2 The test method for an insulation material breakdown test device based on force-electric synchronous measurement includes the following steps: S100. Fix the insulation material to be tested onto the grounding platform, set the puncture speed, high voltage output value, failure judgment threshold and acquisition parameters through the industrial control computer, and perform system self-test. S200 After the self-test is passed, the test program is started. The servo drive module drives the puncture probe to move downward at a set speed. When the force sensor detects that the contact force exceeds the set threshold, the synchronous control module triggers the programmable high voltage source to output the set voltage. At the same time, it triggers the multi-channel synchronous data acquisition system to synchronously record the puncture displacement, puncture force, applied voltage, leakage current and partial discharge signal. S300, based on synchronously acquired multi-channel data, determines the critical point of insulation failure by fusing leakage current mutation criteria, partial discharge initiation criteria and force-displacement penetration characteristic criteria, and records the displacement, force value and time parameters at the corresponding time. S400: Based on recorded data, according to the timing relationship and waveform characteristics of force and electrical signals, it automatically identifies failure modes and generates a test report containing test curves and failure characteristic parameters.

[0067] In this embodiment, the sample is first prepared and the system is configured. The insulating material to be tested (such as a coated metal plate or an insulating film) is placed on a grounded platform and fixed with a clamp to ensure good electrical contact between the material and the platform.

[0068] Set the test parameters in the host computer software: puncture speed (e.g., 1 mm / min), high voltage source output voltage (e.g., 5 kVDC), overcurrent protection threshold (e.g., 5 mA), leakage current sudden change threshold, and partial discharge detection sensitivity.

[0069] Perform a system self-test: confirm that all sensor signals are normal, the high-voltage source output is normal, and the safety interlock is closed.

[0070] Further dynamic puncture and synchronous data acquisition are performed. The test program is started, and the servo motor drives the probe to move toward the material surface at a set speed.

[0071] After the probe contacts the material, if the force sensor signal exceeds the contact threshold (e.g., 0.1 N), the system automatically triggers the high-voltage source to output the set voltage and simultaneously starts data acquisition.

[0072] The data acquisition system continuously records the following parameters: Puncture displacement puncture force Actual voltage Leakage current Partial discharge quantity All signals are recorded using the same time base, with a time synchronization error ≤ 1. .

[0073] The system then performs data processing and insulation failure determination. It automatically determines insulation failure based on the following fusion criteria: Criterion 1: Sudden change in leakage current; Set insulation failure current threshold (e.g. 10) and duration threshold (e.g., 100) ).when And continue to exceed When this occurs, insulation failure is determined. Alternatively, the slope method can be used: when... When the speed reaches 1 mA / ms, insulation failure is considered to have occurred. Record the displacement at this time. with force .

[0074] This threshold is much lower than the system hardware overcurrent protection threshold (e.g., 5 mA), and is used to sensitively detect the first degradation or failure of insulation performance.

[0075] Criterion 2: Partial discharge initiation; Calculate background noise PDnoise. When... Furthermore, when repetitive pulses (more than 3 consecutive pulses) occur, insulation degradation is considered to have begun. Record the displacement at this point. with force .

[0076] Criterion 3: Force-displacement characteristic auxiliary criterion; Force-displacement curves Perform smoothing and calculate the first derivative. .when When a value rapidly changes from a positive value to near zero or negative, and the change exceeds a set threshold (such as 50% of a large slope), it is identified as a penetration point Dpunc.

[0077] like or If the time difference with Dpunc is less than a set threshold (e.g., 10 ms), then the point is confirmed as an insulation failure point, thus improving the reliability of the judgment.

[0078] Criterion 4: Failure Mode Identification; The system according to and Based on waveform characteristics, failure modes are automatically classified: Instantaneous breakdown: The current rises rapidly to the overcurrent protection threshold, and partial discharge occurs briefly (duration <1 ms).

[0079] Gradual degradation: Partial discharge continues to increase (duration > 100 ms), and the current rises slowly and then jumps abruptly.

[0080] Mechanically driven failure: The force-displacement penetration point occurs before the electrical signal abrupt change (Dpunc occurs earlier than...). (More than 10 ms) indicates that the material fractures first and then breaks down.

[0081] Finally, the test report is generated. After the test is completed, the system automatically generates a report, which includes: Test parameter settings, force-displacement curves, leakage current-time curves, partial discharge-time curves, coordinates of insulation failure points (displacement, force, time), failure mode classification results, and data export (CSV format).

[0082] Finally, the embodiments of the present invention will be explained and illustrated with reference to specific examples: Specific Implementation Example 1: Progressive Degradation Test of Polyimide Film under AC Voltage.

[0083] Sample: Polyimide film, 125 μm thick, opaque.

[0084] Test parameter settings: 1) Puncture speed: 0.5 mm / min; 2) High-voltage source output: AC 2 kV (50 Hz); 3) Leakage current failure threshold: 10 μA, duration threshold: 100 μs; 4) Partial discharge detection enabled; background noise threshold: 5 pC; 5) Threshold for the change of the first derivative of the force-displacement curve: 50% of the maximum slope.

[0085] Test Procedure and Expected Results: The thin film sample was fixed on the grounded platform, and the test program was started. The servo motor drove the probe to move downwards at a speed of 0.5 mm / min.

[0086] After the probe contacts the thin film surface, if the force sensor signal exceeds the 0.1 N contact threshold, the system automatically triggers a high-voltage source to output a 2 kV AC voltage and simultaneously starts data acquisition. The acquisition system continuously records the displacement. ,force ,Voltage Leakage current and partial discharge .

[0087] Theoretical derivation: The AC dielectric strength of the polyimide film is approximately 520 Vrms / μm. The 2 kV voltage applied in this embodiment corresponds to an initial electric field strength of 16 kV / mm. According to the formula for calculating the electric field of a parallel plate capacitor, E = U / d, when the probe is pressed in, causing the film to be locally compressed to 30% of its original thickness, the estimated local electric field strength is approximately 53 kV / mm, which exceeds the partial discharge initiation field strength of some common polyimides. Therefore, it can be reasonably predicted that when the probe is pressed into the film but has not yet fully penetrated (the displacement is approximately 70%~90% of the film thickness), a partial discharge signal will begin to appear.

[0088] expected When the amplitude reaches 15 pC or more (greater than 3 times the background noise of 5 pC) and continuous repetitive pulses appear, the system automatically determines that insulation degradation has begun based on criterion two and records the initial displacement of degradation. harmony .

[0089] As the probe continues to press down, the partial discharge intensifies. When the probe tip completely penetrates the film, the first derivative of the force-displacement curve... The value rapidly decreases from positive to near zero (criterion three identifies the penetration point). Simultaneously, the leakage current suddenly increases from the nanoampere level to the milliampere level, triggering criterion one and recording the breakdown displacement. .

[0090] The system automatically compares and The time difference between the two is less than 10 ms, confirming this point as the insulation failure point.

[0091] Failure Mode Identification: Sustained enhancement time greater than 100 ms The failure mode exhibits a slow increase followed by a sudden jump, and the system automatically determines it as "gradual degradation".

[0092] Test report output: The system generates a report including force-displacement curves, leakage current-time curves, and partial discharge-time curves, and outputs the insulation degradation start point (…). (corresponding to displacement X.XX mm) and the point of complete breakdown ( The corresponding displacement (X.XX mm) and the failure mode classification results.

[0093] Specific Implementation Example 2: Mechanically Dominant Failure Test of Silicone Rubber Insulation Layer under DC Voltage.

[0094] Sample: Silicone rubber sheet, 1 mm thick, opaque, applied to the surface of a copper plate.

[0095] Test parameter settings: 1) Puncture speed: 2 mm / min; 2) High-voltage source output: DC 5 kV; 3) Leakage current failure threshold: 10 μA, slope threshold: 1 mA / ms; 4) Partial discharge detection enabled; 5) Force-displacement feature auxiliary criterion threshold: 40% of the maximum slope.

[0096] Test process and expected results: Fix the silicone rubber sample to the grounded platform (copper plate facing down, making good contact with the platform). Start the test, and move the probe downwards at a speed of 2 mm / min.

[0097] Theoretical derivation basis: Silicone rubber has high elasticity and large deformation characteristics (elongation at break can reach 300%~600%), and its volume resistivity is extremely high (> The dielectric strength is approximately 20-30 kV / mm (Ω·cm). Before the probe fully penetrates the rubber layer, due to the material's high dielectric strength and high resistance, the leakage current and partial discharge signal remain at the background noise level. Once the probe mechanically pierces the rubber layer, if it has not yet contacted the copper plate, the circuit remains open, and the electrical signal remains unchanged. Only when the probe makes ohmic contact with the copper plate does the high-voltage circuit close, and the current surge.

[0098] Expected Process: After the probe makes contact, the force-displacement curve shows a non-linear increase, with the force gradually increasing. Before the probe fully penetrates the rubber layer, the electrical signal remains unchanged. Once the force-displacement curve reaches its peak, the first derivative rapidly decreases, and criterion three identifies the penetration point. (The probe tip has physically pierced the rubber layer). At this point, the leakage current still shows no significant change (<1nA).

[0099] After the probe continued to move downwards by approximately 0.2 mm, the probe tip made electrical contact with the copper plate, and the leakage current instantly jumped from <1 nA to >10 μA. Once the criterion is triggered, the breakdown displacement is recorded. .

[0100] The system automatically compares and The time difference. Due to Earlier If the failure time exceeds 10 ms, the system determines the failure mode as "mechanically dominated failure" based on criterion four: the material first undergoes physical fracture, and then electrical breakdown occurs.

[0101] Test report output: The report shows that there is a significant hysteresis between the force-displacement penetration point and the electrical breakdown point, outputting the hysteresis displacement (e.g., 0.2 mm) and time difference (15 ms), indicating that the insulation failure of this material is dominated by mechanical damage, and the electrical safety margin is directly related to the mechanical penetration depth.

[0102] Specific Implementation Example 3: Delamination Failure Test of Resin Layer (Multi-layer Structure) on Copper Clad Laminate Surface.

[0103] Sample: Copper-clad laminate, with a surface resin layer thickness of 100 μm and a copper layer thickness of 35 μm, and is opaque overall.

[0104] Test parameter settings: 1) Puncture speed: 0.3 mm / min; 2) High voltage source output: DC 500V (the probe is connected in series with a 10 MΩ current-limiting resistor and then connected to the positive terminal of the high voltage terminal, with the copper layer grounded). 3) Leakage current failure threshold: 5 μA; 4) Force penetration identification criterion: The force value on the force-displacement curve decreases by ≥25% from the maximum peak value, and does not reach a new high within the following 50 ms; Test process and expected results: Fix the copper-clad laminate sample onto the grounding platform (copper layer facing down in contact with the platform, resin layer facing up). Start the test, and the probe moves downwards at a speed of 0.3 mm / min.

[0105] Theoretical derivation: Copper-clad laminates are composed of an insulating resin layer and a conductive copper layer. The dielectric strength of the resin layer is approximately 20 kV / mm, and the theoretical bulk breakdown voltage for a 100 μm thickness is approximately 2 kV. A 500 V DC voltage (with a safety factor of 4) is selected to ensure the resin layer remains intact during the entire mechanical puncture process. When the probe does not contact the copper layer, the circuit is reliably open, and the leakage current is less than 1 nA. Only when the probe penetrates the resin layer and further punctures the high-resistivity oxide layer on the copper foil surface does a metallic contact form. At 500 V, the oxide layer is tunneled or transiently broken down, the circuit closes, and the current is limited to approximately 50 μA by a 10 MΩ resistor. The force-displacement curve shows a peak at resin penetration and then drops sharply, while the electrical contact event is inevitably delayed due to the presence of the interface layer, thus generating a measurable displacement difference ΔD. This embodiment utilizes this characteristic to distinguish delamination failure.

[0106] Expected Process: The probe first contacts and penetrates the resin layer. The force increases linearly with displacement, and the leakage current remains at the background noise level (<1 nA). The 500 V high-voltage source drops entirely onto the intact resin layer without premature breakdown. After reaching its peak force, the force drops sharply due to resin layer penetration. Criterion three identifies the first penetration point. (If the force value decreases by ≥25% and remains constant), the resin layer has been penetrated, but the probe has not yet formed a stable electrical contact with the copper layer, so the current is still <5 μA. At this time, since the resin layer is an insulating material and the probe has not yet formed a good electrical contact with the copper layer, the leakage current is still at the background level (<1 nA), so the failure judgment is not triggered.

[0107] As the probe continues its downward movement, the circuit resistance drops sharply after piercing the copper foil oxide layer or residual adhesive layer. At this point, a complete circuit is formed through the probe, copper layer, and grounding platform, and the leakage current instantly jumps to >10 μA. Criterion 1 is triggered, and the breakdown displacement is recorded. Meanwhile, the force-displacement curve shows a second peak followed by a falling edge due to the probe pressing against the hard copper layer; criterion three identifies the second penetration point. .

[0108] The system automatically analyzes: and The time difference is less than 10 ms, confirm. This is the point of insulation failure; and Since there was no accompanying change in electrical signal, it was determined to be a simple mechanical penetration event.

[0109] Failure Mode Identification: The system automatically outputs the "delamination failure" characteristic, which means that mechanical penetration (resin layer) and non-electrical failure occur first, followed by electrical breakdown (contact copper layer). The report records the resin layer penetration displacement, the copper layer contact breakdown displacement, and the displacement difference between the two (reflecting the relationship between insulation layer thickness and electrical safety margin).

[0110] The content of the above method embodiments is applicable to this system embodiment. The specific functions implemented in this system embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0111] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this is not intended to limit the scope of the embodiments of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the embodiments of the present application.

Claims

1. A breakdown testing device for insulating materials based on force-electric synchronous measurement, characterized in that, The system includes a support frame, on which are respectively installed a mechanical puncture unit, a high-voltage electrical unit, a signal acquisition and control unit, and a sample grounding unit, wherein: The mechanical puncture unit includes a servo drive module, a force sensor, a displacement sensor, and a puncture probe. The servo drive module is vertically mounted on the upper part of the support frame. The force sensor is fixed to the moving output end of the servo drive module. The puncture probe is coaxially connected to the lower end of the force sensor. The displacement sensor is set to detect the vertical displacement of the puncture probe. The high-voltage electrical unit includes a programmable high-voltage source, a high-voltage probe, and a current detection module. The high-voltage output terminal of the programmable high-voltage source is electrically connected to the puncture probe. The high-voltage probe is connected in parallel in the high-voltage output circuit, and the current detection module is connected in series in the system grounding circuit. The signal acquisition and control unit includes a multi-channel synchronous data acquisition system, an industrial computer, and a synchronous control module. The multi-channel synchronous data acquisition system is connected to the force sensor, displacement sensor, high-voltage probe, and current detection module respectively. The synchronous control module is connected to the servo drive module, programmable high-voltage source, and trigger of the multi-channel synchronous data acquisition system respectively. The industrial computer is communicatively connected to the multi-channel synchronous data acquisition system and the synchronous control module. The sample grounding unit includes a grounding platform and a sample clamp. The grounding platform is located directly below the puncture probe and is electrically connected to the system grounding terminal. The sample clamp is used to fix the insulating material to be tested onto the surface of the grounding platform.

2. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 1, characterized in that, The support frame adopts a double-column adjustable beam structure. The two support columns are vertically fixed on the base. The beam structure is slidably connected to the support columns by a slider for height adjustment. The servo drive module is installed on the beam for horizontal position adjustment through a horizontal adjustment component.

3. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 2, characterized in that, The servo drive module includes a servo motor, a ball screw, and a slide table. The servo motor drives the slide table to perform vertical reciprocating motion through the ball screw. The lower end of the slide table is fixedly connected to a displacement sensor. The displacement sensor includes a grating ruler and a grating reading head. The grating ruler is fixed on the load mounting plate, and the grating reading head is fixed to the side of the slide table.

4. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 3, characterized in that, The programmable high-voltage source is an AC / DC switchable high-voltage source with a built-in hardware overcurrent protection module. The control interface of the programmable high-voltage source supports analog control and digital communication connection.

5. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 4, characterized in that, The current detection module includes a high-frequency current transformer and a low-frequency current transformer. The high-frequency current transformer and the low-frequency current transformer are connected in parallel in the grounding circuit. The high-frequency current transformer is used to detect partial discharge signals, and the low-frequency current transformer is used to detect power frequency leakage current.

6. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 5, characterized in that, The multi-channel synchronous data acquisition system includes a high-speed acquisition channel and a low-speed acquisition channel. The high-speed acquisition channel is connected to a high-frequency current transformer signal, and the low-speed acquisition channel is connected to a force sensor, a displacement sensor, a high-voltage probe, and a low-frequency current transformer signal, respectively. The high-speed acquisition channel and the low-speed acquisition channel are synchronized through a unified system clock source.

7. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 6, characterized in that, The synchronization control module outputs a unified hardware trigger signal, which is distributed to the start-up terminal of the servo drive module, the output control terminal of the programmable high-voltage source, and the external trigger terminal of the multi-channel synchronous data acquisition system.

8. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 7, characterized in that, It also includes a transparent insulating protective cover that covers the high-voltage test area. The transparent insulating protective cover is equipped with a door lock interlock switch, which is connected in series with the control circuit of the programmable high-voltage source and automatically cuts off the high-voltage output when the door is opened.

9. The insulation material breakdown test device based on force-electric synchronous measurement according to claim 8, characterized in that, Electromagnetic shielding plates are respectively installed on both sides of the support frame. The electromagnetic shielding plates correspond to the installation positions of the high-voltage power supply and the industrial control computer. The system operation panel of the electromagnetic shielding plate is equipped with an emergency stop button, which is connected in series in the power supply circuit of the servo drive module and the programmable high-voltage source.

10. A test method for an insulating material breakdown test device based on force-electric synchronous measurement, characterized in that, Includes the following steps: The insulating material to be tested is fixed on the grounding platform. The puncture speed, high voltage output value, failure judgment threshold and acquisition parameters are set by the industrial control computer, and the system self-test is executed. After the self-test is passed, the test program is started. The servo drive module drives the puncture probe to move downward at a set speed. When the force sensor detects that the contact force exceeds the set threshold, the synchronous control module triggers the programmable high voltage source to output the set voltage, and at the same time triggers the multi-channel synchronous data acquisition system to synchronously record the puncture displacement, puncture force, applied voltage, leakage current and partial discharge signal. Based on synchronously acquired multi-channel data, the critical point of insulation failure is determined by fusing leakage current mutation criteria, partial discharge initiation criteria, and force-displacement penetration characteristic criteria, and the displacement, force value, and time parameters at the corresponding time are recorded. Based on the recorded data, and according to the timing relationship and waveform characteristics of the force and electrical signals, the system automatically identifies the failure modes and generates a test report containing test curves and failure characteristic parameters.

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