Automatic measurement apparatus for insulating property of thin-film material

Abstract

An automatic measurement apparatus for an insulating property of a thin-film material, which apparatus belongs to the technical field of conductive current measurement apparatuses. The automatic measurement apparatus comprises a temperature-controlled sample stage, a program-controlled switch box, a voltage sensor, a current sensor, a power source and a controller, wherein the temperature-controlled sample stage comprises a test box, a temperature sensor, a humidity sensor, a test electrode unit, an electrolytic aluminum plate, an insulating plate, a heating plate and a cover plate, the test electrode unit, the electrolytic aluminum plate, the insulating plate and the heating plate are arranged in a box cavity from bottom to top, the test electrode unit is provided with a plurality of independent test electrodes, and a plurality of positive electrodes of the test electrode unit are electrically connected to the program-controlled switch box, respectively; the program-controlled switch box is electrically connected to the controller and the power source, respectively; and the controller is electrically connected to the voltage sensor, the current sensor, the temperature sensor and the humidity sensor, respectively. The automatic measurement apparatus has the advantage that the resistance, resistivity and breakdown voltage of an insulating film in different temperature and humidity conditions can be provided, and is used for quality assessment performed on the insulating film.

Description

An automatic measuring device for insulating properties of thin film materials Technical Field

[0001] The invention belongs to the technical field of conduction and current measuring devices, and in particular relates to an automatic measuring device for the insulation performance of a thin film material. Background Art

[0002] Insulating materials, also known as dielectrics, allow only a tiny amount of current to flow under an applied voltage. In electrical product construction, insulating materials are used to separate conductors with different electrical potentials, electrically isolating the device and preventing current from flowing through it. Furthermore, materials with polarization properties are called dielectrics. Solid insulating materials are categorized into bulk and thin-film materials based on their form. Thin-film insulating materials and dielectric materials are widely used in electrical products such as motors, transformers, and capacitors, as well as in electronic components.

[0003] In addition to electrical resistance, another important characteristic of insulating materials is withstand voltage, typically measured in units of voltage per micron (electrical strength, V / µm). According to GBT / T 13542.2, DC testing of insulating materials typically uses a 50-point electrode method. For example, polypropylene film has a withstand voltage of 600 V / µm. If the film is 5 µm thick, the test voltage must be at least 3000 V. The existing single-point test method, which measures data from 50 points, is extremely inefficient.

[0004] Furthermore, the resistance and voltage resistance of insulating materials, especially at high temperatures, are also dependent on environmental conditions such as temperature and humidity, as well as the material preparation and molding processes. In particular, factors such as molding process and temperature directly affect the crystal structure and surface morphology, which in turn directly impact the film's voltage resistance, especially at high temperatures. Existing measurement devices are limited in their inability to measure resistance and voltage resistance under varying temperature and humidity conditions.

[0005] In view of the above-mentioned prior art, it is necessary to improve the structure of the existing thin film material insulation performance measurement device. To this end, the applicant has made a useful design, and the technical solution to be introduced below was produced in this context. Summary of the Invention

[0006] The purpose of the present invention is to provide an automatic measuring device for the insulation properties of thin film materials, which can provide relevant experimental data under different temperatures and humidity, thereby improving the measurement efficiency and increasing the operational safety.

[0007] The object of the present invention is achieved in this way. A device for automatically measuring the insulation properties of thin film materials includes a temperature-controlled sample stage, a programmable switch box, a voltage sensor, a current sensor, a power supply and a controller. The temperature-controlled sample stage includes a test box, a temperature sensor, a humidity sensor, a test electrode unit, an electrolytic aluminum plate, an insulating plate, a heating plate and a cover plate. The test box has a box cavity with an opening formed on the upper end surface. The temperature sensor and the humidity sensor are installed at the bottom of the box cavity. The test electrode unit, the electrolytic aluminum plate, the insulating plate and the heating plate are arranged in the box cavity from bottom to top. The cover plate covers the opening of the test box. The test electrode unit has multiple independent test electrodes. The electrolytic aluminum plate is configured as a negative electrode corresponding to the positive electrode. The multiple positive electrodes of the test electrode unit are respectively electrically connected to the programmable switch box. The programmable switch box is respectively electrically connected to the controller and the power supply. The controller is respectively electrically connected to the voltage sensor, the current sensor, the temperature sensor and the humidity sensor. The voltage sensor is connected in parallel at both ends of the power supply, and the current sensor is connected in series between the electrolytic aluminum plate and the power supply.

[0008] In a specific embodiment of the present invention, the test electrode unit includes an electrode unit mounting frame and a plurality of mounting bars arranged in parallel and at intervals on the electrode unit mounting frame, and the test electrodes are arranged at intervals on each mounting bar.

[0009] In another specific embodiment of the present invention, the electrode unit mounting frame is provided with grooves spaced apart on a set of parallel symmetrical frames along the length direction, and the mounting strip extends mounting ends at both ends, and the mounting ends are mounted in conjunction with the grooves and fastened by fasteners.

[0010] In another specific embodiment of the present invention, the test electrode includes an electrode end, a spring and a wiring terminal, the electrode end forms a connecting section at the bottom, an electrode hole is opened on the mounting bar corresponding to the test electrode, a step is formed in the middle of the electrode hole in the height direction for limiting the electrode end, the electrode end is inserted into the electrode hole, the spring is sleeved on the connecting section, and one end rests on the bottom of the electrode end, and the other end rests on the step, the wiring terminal is provided with a threaded section protruding from the top, and the threaded section extends into the electrode hole from the bottom of the mounting bar and is threadedly connected to the connecting section of the electrode end.

[0011] In another specific embodiment of the present invention, the electrode unit mounting frame is made of insulating and heat-resistant material; and the test electrode is a metal electrode made of electrolytic aluminum.

[0012] In another specific embodiment of the present invention, there are ten mounting bars, and each mounting bar is provided with five test electrodes.

[0013] In a further specific embodiment of the present invention, the planarity between the test electrodes is less than 0.2 mm.

[0014] Due to the adoption of the above-mentioned structure, the present invention has the following beneficial effects compared with the prior art: it can provide basic performance parameters such as resistance, resistivity and breakdown voltage (electric field strength) of the insulating film under different temperature and humidity conditions, which can be used for quality evaluation of the insulating film and also provide a test means for studying the resistance, withstand voltage and other characteristics of the insulating film; it not only improves the measurement efficiency but also has high operational safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] FIG1 is a block diagram of the overall circuit of the present invention;

[0016] FIG2 is an exploded view of the structure of the temperature-controlled sample stage according to the present invention;

[0017] FIG3 is a schematic structural diagram of the test electrode according to the present invention.

[0018] In the figure: 1. Temperature-controlled sample table, 11. Test chamber, 111. Chamber cavity, 112. Wire hole, 12. Temperature sensor, 13. Humidity sensor, 14. Test electrode unit, 141. Test electrode, 1411. Electrode end, 14111. Connecting section, 1412. Spring, 1413. Wiring terminal, 14131. Threaded section, 142. Electrode unit mounting frame, 1421. Groove, 143. Mounting bar, 1431. Mounting end, 1432. Electrode hole, 14321. Step, 15. Electrolytic aluminum plate, 16. Insulation plate, 17. Heating plate, 18. Cover; 2. Programmable switch box; 3. Voltage sensor; 4. Current sensor; 5. Power supply; 6. Controller. DETAILED DESCRIPTION

[0019] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. However, the description of the embodiments does not limit the technical solutions. Any changes in form rather than substance based on the concept of the present invention should be considered as the scope of protection of the present invention.

[0020] In the following description, all concepts related to directionality (or orientation) such as up, down, left, right, front and back are with respect to the position state of the figure being described. The purpose is to facilitate public understanding, and therefore it cannot be understood as a special limitation on the technical solution provided by the present invention.

[0021] Referring to Figures 1 and 2, an automatic measuring device for the insulation properties of thin film materials includes a temperature-controlled sample stage 1, a programmable switch box 2, a voltage sensor 3, a current sensor 4, a power supply 5, and a controller 6. The temperature-controlled sample stage 1 comprises a test chamber 11, a temperature sensor 12, a humidity sensor 13, a test electrode unit 14, an electrolytic aluminum plate 15, an insulating plate 16, a heating plate 17, and a cover 18. The test chamber 11 has a chamber 111 with an opening formed on its upper end. The temperature sensor 12 and humidity sensor 13 are mounted at the bottom of the chamber 111. The test electrode unit 14, the electrolytic aluminum plate 15, the insulating plate 16, and the heating plate 17 are arranged from bottom to top within the chamber 111, with the cover 18 covering the opening of the test chamber 11. The test electrode unit 14 comprises multiple independent test electrodes 141. These test electrodes 141 are metal electrodes made of electrolytic aluminum and provide positive electrodes for testing. The electrolytic aluminum plate 15 has a smooth and flat surface and provides a negative electrode for testing. During testing, the insulating film under test is placed between the test electrode unit 14 and the electrolytic aluminum plate 15, thereby connecting the positive and negative electrodes. The insulating plate 16 ensures insulation between the heating plate 17 and the negative electrode; the heating plate 17 provides a stable temperature field for testing insulation performance at high temperatures. The cover plate 18 provides safety protection, using its own weight to ensure reliable contact between the insulating film under test and the electrodes while sandwiched between the positive and negative electrodes.

[0022] Furthermore, the multiple test electrodes 141 of the test electrode unit 14 are electrically connected to the program-controlled switch box 2, which is electrically connected to the controller 6 and the power supply 5. The controller 6 is electrically connected to the voltage sensor 3, current sensor 4, temperature sensor 12, and humidity sensor 13. The voltage sensor 3 is connected in parallel across the power supply 5, and the current sensor 4 is connected in series between the electrolytic aluminum plate 15 and the power supply 5.

[0023] In order to facilitate combination and testing, in this embodiment, the test electrode unit 14 is composed of five test electrodes 141 into a group. Of course, other combinations can be made according to the size of the test material, and it is not limited to five in a group. In this embodiment, the test electrode unit 14 includes an electrode unit mounting frame 142, and ten mounting bars 143 arranged in parallel and at intervals on the electrode unit mounting frame 142. Five of the test electrodes 141 are arranged at intervals on each mounting bar 143, and automatic testing of fifty points is achieved under the control of the programmable switch box 2 and the controller 6. The electrode unit mounting frame 142 is provided with grooves 1421 at intervals on a group of symmetrical frames arranged in parallel along the length direction. The mounting bars 143 extend mounting ends 1431 at both ends. The mounting ends 1431 are installed in conjunction with the grooves 1421 and are fastened by fasteners.

[0024] Please see Figure 3. The test electrode 141 includes an electrode end 1411, a spring 1412 and a terminal 1413. The electrode end 1411 forms a connecting section 14111 at the bottom. The mounting bar 143 is provided with an electrode hole 1432 corresponding to the test electrode 141. The electrode hole 1432 is formed with a step 14321 in the middle of the height direction for limiting the electrode end 1411. The electrode end 1411 is inserted into the electrode hole 1432. The spring 1412 is sleeved on the connecting section 14111, with one end resting on the bottom of the electrode end 1411 and the other end resting on the step 14321. The terminal 1413 is provided with a threaded section 14131 at the top. The threaded section 14131 extends from the bottom of the mounting bar 143 into the electrode hole 1432 and is threadedly connected to the connecting section 14111 of the electrode end 1411. The test electrodes 141 are designed to have a flatness of less than 0.2 mm relative to each other. This ensures not only a flat and smooth top surface of the electrode ends 1411 in contact with the insulating film being tested, but also a substantially consistent pressure between each test electrode 141. The weight of the cover plate 18 and the built-in springs 1412 of the test electrodes 141 ensure good contact and consistent pressure between the positive and negative electrodes and the insulating film being tested, ensuring measurement accuracy. In this embodiment, the electrode unit mounting frame 142 is made of an insulating and heat-resistant material, such as flame-retardant FR4 epoxy board.

[0025] The fifty test electrodes 141 are tested in a preset sequence through the programmable switch box 2 under the control of the controller 6. The controller 6 is preferably a PLC, preferably model JYCL-01, and the programmable switch box 2 is preferably model JYCL-KGX. If the dimensions of the insulating film being tested meet the standard requirements, the fifty-point test can be completed in a single test. If the dimensions of the insulating film being tested do not meet the standard requirements, the number of test points and the position of the test electrodes 141 corresponding to the material can be set for each test, ultimately completing the fifty-point test required by the standard. Specifically, the test voltage is obtained by the voltage sensor 3 from both ends of the output line of the power supply 5, the leakage current is obtained by the current sensor 4 installed on the output line of the power supply 5, and the temperature and humidity data within the test box 11 are measured by the temperature sensor 12 and the humidity sensor 13. Corresponding to the fifty test electrodes 141, the programmable switch box 2 has fifty switches. One end of each switch is connected to the controller 6, and the other end is electrically connected to each of the fifty test electrodes 141 via output lines. The side walls of the test box 11 are provided with wire holes 112 for the passage of cables. Parameters such as the starting voltage, ending voltage, and voltage rise rate are set according to the relevant test requirements. Under the control of the controller 6, each time a switch in the programmable switch box 2 is turned on, the relevant test data is recorded. Based on the relevant test data, basic performance parameters of the insulating material, such as the resistance, resistivity, and breakdown voltage (electric field strength) of the tested insulating film, can be calculated. Here, resistance = test voltage / leakage current, and breakdown field strength = test voltage / film thickness. The controller 6 and programmable switch box 2 are used in this embodiment using conventional techniques, and a detailed description is omitted here.

[0026] During the test, controller 6 presets a starting voltage value U0 (e.g., 300V) and an ending voltage value (e.g., 3000V). The number of measurements, for example, is set to 10. Controller 6 then divides the voltage value for each measurement to (3000-300) / 10 = 270V. This value also serves as the test voltage step, resulting in test voltages of 300V, 570V, 840V, and so on. The leakage current measured by current sensor 4 is recorded for each measurement. The resistance value and breakdown field strength are calculated using the formula: resistance = test voltage / leakage current. If the leakage current exceeds 10mA, the test is terminated and the withstand voltage is determined to be below the test voltage at that point.

[0027]

Claims

1. An automatic measuring device for the insulation performance of thin film materials, characterized in that: The invention comprises a temperature-controlled sample platform (1), a program-controlled switch box (2), a voltage sensor (3), a current sensor (4), a power supply (5) and a controller (6); the temperature-controlled sample platform (1) comprises a test box (11), a temperature sensor (12), a humidity sensor (13), a test electrode unit (14), an electrolytic aluminum plate (15), an insulating plate (16), a heating plate (17) and a cover plate (18); the test box (11) has a box cavity (111) with an opening formed on the upper end surface; the temperature sensor (12) and the humidity sensor (13) are installed at the bottom of the box cavity (111); the test electrode unit (14), the electrolytic aluminum plate (15), the insulating plate (16) and the heating plate (17) are arranged in the box cavity (111) from bottom to top; The cover plate (18) covers the opening of the test box (11), the test electrode unit (14) has a plurality of independent test electrodes (141), the electrolytic aluminum plate (15) is configured as a negative electrode corresponding to the positive electrode, the plurality of positive electrodes of the test electrode unit (14) are respectively electrically connected to the program-controlled switch box (2), the program-controlled switch box (2) is respectively electrically connected to the controller (6) and the power supply (5), the controller (6) is respectively electrically connected to the voltage sensor (3), the current sensor (4), the temperature sensor (12) and the humidity sensor (13), the voltage sensor (3) is connected in parallel to both ends of the power supply (5), and the current sensor (4) is connected in series between the electrolytic aluminum plate (15) and the power supply (5).

2. The device for automatically measuring the insulation performance of thin film materials according to claim 1, characterized in that The test electrode unit (14) comprises an electrode unit mounting frame (142) and a plurality of mounting bars (143) arranged in parallel and at intervals on the electrode unit mounting frame (142), and the test electrodes (141) are arranged at intervals on each mounting bar (143).

3. The automatic measuring device for insulating properties of thin film materials according to claim 2, characterized in that The electrode unit mounting frame (142) is provided with grooves (1421) at intervals on a set of symmetrical frames arranged in parallel along the length direction, and the mounting strip (143) extends mounting ends (1431) at both ends, and the mounting ends (1431) are mounted in cooperation with the grooves (1421) and fastened by fasteners.

4. The device for automatically measuring the insulation performance of thin film materials according to claim 2, characterized in that The test electrode (141) comprises an electrode end (1411), a spring (1412) and a terminal (1413); the electrode end (1411) forms a connecting section (14111) at the bottom; an electrode hole (1432) is provided on the mounting bar (143) corresponding to the test electrode (141); a step (1432) is formed in the middle of the electrode hole (1432) in the height direction for limiting the position of the electrode end (1411); the electrode end (1411) ) is inserted into the electrode hole (1432), the spring (1412) is sleeved on the connecting section (14111), and one end abuts against the bottom of the electrode end (1411), and the other end abuts against the step (1432), the wiring terminal (1413) is provided with a threaded section (14131) protruding from the top, and the threaded section (14131) extends from the bottom of the mounting strip (143) into the electrode hole (1432) and is threadedly connected to the connecting section (14111) of the electrode end (1411).

5. The device for automatically measuring the insulation performance of thin film materials according to claim 4, characterized in that The electrode unit installation frame (142) is made of insulating and heat-resistant material; the test electrode (141) is a metal electrode made of electrolytic aluminum.

6. The automatic measuring device for insulating properties of thin film materials according to claim 2, characterized in that There are ten installation bars (143), and five test electrodes (141) are arranged on each installation bar (143).

7. The device for automatically measuring the insulation performance of thin film materials according to claim 1, characterized in that The flatness between the test electrodes (141) is less than 0.2 mm.

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