Motor anti-halo material corona resistance performance test device, system and method

Abstract

The application discloses a motor anti-corona material corona resistance performance test device, system and method, relates to the high-voltage motor insulation technical field, and the test device comprises a plate electrode assembly and a blade electrode, the plate electrode assembly is used for bearing a sample to be tested, and a grounding electrode is fixed to the lower surface of the plate electrode assembly; the bottom of the blade electrode has a straight line blade with a length of 50 mm+ / -0.1 mm, the main body curvature radius of the blade cross-section profile is 0.22 mm+ / -0.008 mm, the straight line blade is formed by the intersection of two inclined sides, the blade included angle is 53.14 DEG, and the corner at the length direction end has a roundness with a diameter of 3 mm+ / -0.2 mm; during the test, a uniform and spacing-adjustable discharge gap is formed between the surface of the straight line blade and the surface of the sample to be tested on the upper surface of the plate electrode assembly. The application solves the problems that the existing test device cannot simulate a real non-uniform electric field and is difficult to produce standardized corona erosion, and realizes efficient and repeatable quantitative evaluation of the corona resistance performance of the anti-corona material.

Description

Technical Field

[0001] This invention relates to the field of high-voltage motor insulation technology, and more particularly to the performance testing of motor anti-corona materials, and more specifically to a device, system and method for testing the corona resistance performance of motor anti-corona materials. Background Technology

[0002] Anti-corona structure is a key component in the stator winding of a motor used to suppress excessive local electric field strength and prevent corona discharge. With the continuous increase in unit capacity and voltage levels, anti-corona materials are required to not only have good voltage equalization capabilities but also excellent corona resistance after corona discharge occurs. Therefore, to eliminate or reduce the impact of corona discharge on anti-corona materials, it is necessary to evaluate the corona resistance performance of motor anti-corona materials.

[0003] Traditional testing methods for anti-corona materials, such as withstand voltage tests under constant voltage, have significant shortcomings in terms of technical principles. They are unable to effectively simulate the complex non-uniform electric field, high-temperature environment, and long-term corona discharge accumulation effects experienced by the stator winding ends of high-voltage motors during actual operation. Because these test conditions are severely out of sync with actual operating conditions, the test results often fail to accurately reflect the performance degradation behavior of materials under the combined effects of long-term electrical and thermal stress, resulting in a lack of effective prediction and assessment capabilities for the long-term reliability of materials in actual operation.

[0004] More importantly, the aforementioned shortcomings in the technical principles directly lead to severe challenges at the engineering application level. Firstly, the inefficiency of traditional single-point, sequential testing methods and the lengthy aging test cycles significantly lag behind the timeliness requirements of rapid material research and development iteration and large-scale quality control. Simultaneously, the industry has long lacked a standardized testing device and unified method capable of generating stable, repeatable, and quantifiable corrosion morphologies, resulting in poor comparability of test data from different institutions and batches, making it difficult to establish objective and impartial criteria for material performance evaluation and selection. Therefore, this dual deficiency in both the reliability of the technical principles and the efficiency of engineering applications jointly restricts the technological advancement of anti-corona materials and the further improvement of the insulation reliability of high-voltage motors, urgently requiring a new method that simultaneously satisfies the requirements of scientific testing, high efficiency, and standardization. Summary of the Invention

[0005] This invention provides a device, system, and method for testing the corona resistance of motor anti-corona materials, in order to solve the problems that existing tests cannot simulate real non-uniform electric fields and are difficult to generate standardized corona erosion, and to make up for the shortcomings of traditional methods such as low efficiency and poor repeatability and comparability of results.

[0006] This invention is achieved through the following technical solution: On one hand, this invention discloses a testing device for the corona resistance performance of motor anti-corona materials. The testing device includes a plate electrode assembly and a blade electrode corresponding to the plate electrode assembly and suspended directly above the plate electrode. The plate electrode assembly is made of an insulating mica substrate and is used to support the anti-corona material test sample. Copper foil or aluminum foil is pasted on the lower surface of the plate electrode assembly to form a grounding electrode for grounding. The blade electrode is made of brass and has a straight blade with a length of 50 mm ± 0.1 mm at its bottom. The cross-sectional profile of the straight blade is configured such that the main body has a radius of curvature of 0.22 mm ± 0.008 mm and the corners at both ends along the length direction have a rounded diameter of 3 mm ± 0.2 mm. The straight blade is formed by the intersection of two inclined side surfaces, forming a blade angle of 53.14°. During the test, the blade electrode is suspended and fixed directly above the plate electrode assembly, with the two perpendicular to each other. A uniform discharge gap is formed between the straight blade of the blade electrode and the surface of the test sample that is attached to the upper surface of the plate electrode assembly. The spacing of the discharge gap is adjustable.

[0007] Preferably, the blade electrode is suspended and fixed on a support adjustment screw. The two ends of the support adjustment screw are supported on gap adjustment plates provided on both sides of the plate electrode assembly. The gap adjustment plates have strip-shaped adjustment holes extending in the vertical direction. The two ends of the support adjustment screw are located in the strip-shaped adjustment holes of the gap adjustment plates on both sides and can move up and down in the vertical direction in the strip-shaped adjustment holes to adjust the discharge gap formed between the straight blade and the test sample below.

[0008] Preferably, locking nuts are fitted onto the threads at both ends of the support adjusting screw. After the end of the support adjusting screw passes through the strip-shaped adjusting hole, it is locked and fixed to the gap adjusting plate by the locking nuts.

[0009] On the other hand, the present invention also discloses a corona resistance performance testing system for motor anti-corona materials. The corona resistance performance testing system includes the aforementioned corona resistance performance testing device for motor anti-corona materials and a transformer. The testing device is fixedly set on a horizontal mounting platform. The blade electrode is connected to the transformer through a wire to conduct electricity, and the voltage of the transformer is applied to the testing device. Preferably, to facilitate systematic and batch testing of various anti-corona materials, several of the aforementioned corona resistance testing devices are sequentially and fixedly arranged on the mounting platform. Using a column or row as a reference, multiple corona resistance testing devices in each column or row constitute a column or row of motor anti-corona material corona resistance testing units. Furthermore, the discharge gap distance between the testing devices in each column or row and the surface of the sample to be tested is the same. These multiple columns or rows of motor anti-corona material corona resistance testing units constitute a multi-channel parallel testing system, achieving efficient and repeatable quantitative evaluation of the corona resistance performance of anti-corona materials.

[0010] Preferably, each column or row of corona resistance test unit has at least one gap adjustment plate at each end, and the gap adjustment plate has a strip-shaped adjustment hole. For the test device of the same column or row, the blade electrodes are all suspended on the same set of support adjustment screws, which are connected in series to form a whole. The two ends of the support adjustment screws are located in the strip-shaped adjustment holes of the gap adjustment plates at both ends and can move up and down in the vertical direction in the strip-shaped adjustment holes to uniformly adjust the discharge gap formed between the straight blade and the sample surface of the column or row. The support adjustment screws are connected to the transformer through wires to conduct electricity, and the voltage of the transformer is applied to each blade electrode. The support adjustment screws are also made of conductive metal materials such as brass.

[0011] A set of support adjustment screws typically includes two screws, which pass through the two upper corners of the blade electrode to provide stable support for the blade electrode, suspending it and fixing it directly above the plate electrode assembly, while maintaining a perpendicular relationship between the two in spatial position.

[0012] Preferably, in test devices located in the same column or row, the distance between the center lines of two adjacent blade electrodes is not less than 50 mm to prevent electrode discharge from damaging adjacent samples and interfering with the test results.

[0013] Furthermore, this invention discloses a method for testing the corona resistance performance of motor anti-corona materials. The method utilizes the aforementioned corona resistance testing apparatus and includes the following steps: Step S1: Apply the anti-corona paint to be tested evenly to the upper surface of the plate electrode assembly to form a coating sample, or fix the anti-corona tape to be tested flatly to the upper surface of the plate electrode assembly to form an anti-corona tape sample, and then set a grounding electrode on the lower surface of the plate electrode assembly. Step S2: Select a portion of each sample type as a sample, conduct a preliminary experiment using an ultraviolet imager, adjust the test voltage applied to the test device, observe and calibrate the discharge intensity of the discharge gap, and determine the voltage value corresponding to aging tests of various samples under the same discharge intensity. Step S3: Adjust the distance between the straight blade of the blade electrode and the surface of the remaining sample to the set discharge gap; then place the test device in a programmable temperature-controlled oven, raise the temperature to 120°C and stabilize it, apply the corresponding test voltage calibrated in step S2, so that the discharge gap discharges stably, and start timing to carry out the aging test. Step S4, Performance Testing and Evaluation: After each set aging cycle, the sample is removed, cooled to room temperature, and then the sample is visually inspected and its surface resistivity is tested. The performance changes with aging time are recorded and analyzed.

[0014] Preferably, the specific requirements for sample preparation in step S1 include: For the formed anti-halo paint coating sample, the coating area size is 90mm×70mm, and the anti-halo paint is applied twice on the plate electrode assembly to form the anti-halo paint coating sample. Furthermore, when the sample type is a low-resistance anti-halo paint coating sample, the average thickness of the paint film after curing is 0.1mm ± 0.01mm; Furthermore, when the sample type is a high-resistance anti-halo paint coating sample, the average thickness of the paint film after curing is 0.15mm ± 0.01mm.

[0015] Preferably, the anti-halo band sample is fixed at both ends to the plate electrode assembly using epoxy adhesive to keep it flat.

[0016] During the test, the effective number of each type of sample shall not be less than 5, and all samples shall be dried at 60°C for 2 hours before the test to remove moisture.

[0017] In this invention, the types of samples are mainly low-resistivity anti-halo paint coating samples, high-resistivity anti-halo paint coating samples, high-resistivity anti-halo tape samples, and low-resistivity anti-halo tape samples.

[0018] Preferably, in step S3, the heating rate and cooling rate of the oven are both controlled to not exceed 1℃ / min.

[0019] Preferably, in step S4, the performance testing and evaluation selectively adds specific test items for different sample types, as follows: When the sample type is an anti-splatter paint coating sample, an additional paint film adhesion test is performed on the sample. When the sample type is a high-resistance anti-halo paint coating sample or a high-resistance anti-halo tape sample, the calculation of the nonlinear coefficient of the sample is also included. β The calculation method is as follows: ; in, ρ a and ρ b Electric field strength E a and E b The surface resistivity below.

[0020] In this invention, the anti-corona paint and anti-corona tape used in step S1 to prepare the sample are both anti-corona materials applied to the outer layer of the stator bar of a high-voltage motor.

[0021] The beneficial effects of this invention are mainly reflected in the following aspects: 1. The test apparatus of the present invention achieves efficient, batch, and repeatable quantitative evaluation of the corona resistance performance of anti-corona materials through a precisely designed blade-plate electrode and multi-channel parallel testing.

[0022] 2. Based on visual inspection and surface resistivity testing, this invention adds specific tests according to the sample type: for anti-halo paint coating samples, a paint film adhesion test is added to obtain the adhesion of the sample and help judge the anti-detachment performance of the sample; for high-resistivity anti-halo paint and high-resistivity anti-halo tape samples, its nonlinear coefficient β is calculated and a specific calculation formula is provided, realizing the quantitative evaluation of the key electrical performance of anti-halo materials.

[0023] 3. This invention uses an ultraviolet imager to calibrate the discharge intensity and strictly controls the blade-plate gap size, test temperature and test voltage, which solves the problems of being unable to simulate a real non-uniform electric field and the difficulty in standardizing corona erosion. Attached Figure Description

[0024] The present invention will now be further described in detail with reference to the accompanying drawings and specific embodiments: Figure 1 This is a schematic diagram of the experimental device structure of the present invention; Figure 2 This is a front view of the blade electrode of the present invention; Figure 3 This is a side view of the blade electrode of the present invention; Figure 4 This is a schematic diagram of the experimental system of the present invention; Figure 5 This is the electrode electric field distribution curve with a gap of 2 mm in Embodiment 3 of the present invention; Figure 6 This is the electrode electric field distribution curve with a gap of 5 mm in Embodiment 3 of the present invention; Figure 7 This is the electrode electric field distribution curve with a gap of 10 mm in Embodiment 3 of the present invention; Figure 8 The results of the corona resistance test of the high-resistance anti-corona paint 1 in Example 3 of this invention. Figure 9 The results of the corona resistance test for the high-resistance anti-corona paint 2 in Example 3 of this invention; Figure 10 The results of the corona resistance test of the high-resistance anti-corona paint 3 in Example 3 of the present invention are shown.

[0025] In the attached image: 1. Blade electrode; 2. Plate electrode assembly; 3. Test sample; 11. Straight blade; 41. Mounting platform; 42. Gap adjustment plate; 43. Strip adjustment hole; 44. Adjustment support screw. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solutions of this invention, several specific embodiments will be used to further illustrate the technical solutions for achieving the objectives of this invention. It should be noted that the technical solutions claimed by this invention include, but are not limited to, the following embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort should fall within the scope of protection of this invention.

[0027] Example 1 This embodiment discloses a testing device for the corona resistance performance of motor anti-corona materials. Figure 1 This is a schematic diagram of the corona resistance testing device of the present invention. First, as shown... Figure 1 As shown, the test apparatus includes a plate electrode assembly and a blade electrode 1 corresponding to the plate electrode assembly. The blade electrode 1 is located directly above the plate electrode assembly 2, and the two are perpendicular to each other; wherein, The plate electrode assembly 2 is made of an insulating mica substrate and is used to support the anti-corona material test sample 3. More specifically, the upper surface of the plate electrode assembly 2 supports the test sample 3, and the lower surface is attached with copper foil or aluminum foil to form a grounding electrode, so that the entire plate electrode assembly 2 is grounded. The blade electrode 1 is made of brass with good electrical conductivity, such as... Figure 2 and Figure 3 As shown, the bottom of the blade electrode 1 has a straight blade 11 with a length of 50 mm ± 0.1 mm; the cross-sectional profile of the straight blade 11 is configured such that its main body has a radius of curvature of 0.22 mm ± 0.008 mm, the corners at both ends along the length direction have rounded edges with a diameter of 3 mm ± 0.2 mm, and the straight blade 11 is formed by the intersection of two inclined side surfaces, with the blade included angle of 53.14°.

[0028] During the test, the blade electrode 1 is positioned perpendicular to and directly opposite the plate electrode assembly 2, suspended above the plate electrode assembly 2 on which the test sample 3 is attached, thereby forming a uniform discharge gap between its straight blade 11 and the sample surface, and the spacing of the discharge gap is adjustable.

[0029] The blade electrode 1 can move vertically up and down relative to the plate electrode assembly to adjust the spacing of the discharge gap formed between the straight blade 11 and the sample surface. For details, please refer to the appendix to the instruction manual. Figure 4 As shown, the blade electrode 1 is fixedly mounted on the support adjustment screw 44. A gap adjustment plate 42 is provided on each side of the plate electrode assembly 2. The gap adjustment plate 42 has a vertically extending strip-shaped adjustment hole 43. The two ends of the support adjustment screw 44 are located in the strip-shaped adjustment holes 43 of the gap adjustment plates 42 on both sides, and can move up and down in the vertical direction in the strip-shaped adjustment holes 43, thereby driving the blade electrode 1 fixed on it to move up and down together, so as to adjust the size of the discharge gap formed between the straight blade 11 and the surface of the test sample 3.

[0030] Furthermore, locking nuts are respectively fitted onto the threads at both ends of the support adjusting screw 44. After the end of the support adjusting screw 44 passes through the strip-shaped adjusting hole 43, it is locked and fixed to the gap adjusting plate 42 by the locking nuts.

[0031] In the embodiments described in this invention, the width of the discharge gap has been verified to be optimally 2 mm ± 0.1 mm.

[0032] Example 2 This embodiment discloses a test system for the corona resistance performance of motor anti-corona materials. The test system includes a transformer and the test device for the corona resistance performance of motor anti-corona materials described in Embodiment 1 above. The test device is fixedly installed on the mounting platform 41, and the blade electrode 1 of the test device is connected to the transformer of the system through a wire. In order to batch test the samples, such as Figure 4 As shown, several of the aforementioned corona resistance testing devices are arranged and fixedly set on the mounting platform. Using a column or row as a reference, multiple corona resistance testing devices in each column or row form a column or row of corona resistance testing units for motor anti-corona materials. Furthermore, the discharge gap distance between each column or row of testing devices and the surface of the test sample 3 is the same. These multiple columns or rows of motor anti-corona material corona resistance testing units constitute a multi-channel parallel testing system, achieving efficient and repeatable quantitative evaluation of the corona resistance performance of anti-corona materials.

[0033] Preferably, each column or row of corona resistance test unit has at least one gap adjustment plate 42 at both ends. The gap adjustment plate 42 has a strip-shaped adjustment hole 43. For the test device of the same column or row, the blade electrodes 1 are all suspended on the same set of support adjustment screws 44. The support adjustment screws 44 connect the test units of the column into a whole. The two ends of the support adjustment screws 44 are located in the strip-shaped adjustment holes 43 of the gap adjustment plates 42 at both ends and can move up and down in the vertical direction in the strip-shaped adjustment holes 43, thereby driving the blade electrodes 1 fixed on them to move up and down together, and uniformly adjusting the discharge gap formed between the straight blades 11 and the sample surface of the column or row. The support adjustment screws 44 are connected to the transformer through wires and the voltage of the transformer is applied to each blade electrode 1. Therefore, the support adjustment screws 44 are also made of conductive metal materials such as brass.

[0034] A set of support adjustment screws typically includes two support adjustment screws 44, which pass through the two upper corners of the blade electrode 1 respectively, providing stable support for the blade electrode 1 and suspending it directly above the plate electrode assembly 2, while maintaining a vertical spatial relationship between the two.

[0035] Furthermore, it is understandable that in order to prevent electrode discharge from damaging adjacent samples and interfering with the test results, the distance between the center lines of two adjacent blade electrodes 1 in the test apparatus located in the same column or row should not be less than 50 mm.

[0036] Example 3 This embodiment discloses a test method for the corona resistance performance of motor anti-corona materials. The test method is based on the test device of Embodiment 1 or the test system of Embodiment 2, and the specific steps are as follows: S1. Sample Preparation The test samples 3 involved in this embodiment include high-resistance anti-halo paint coating samples, low-resistance anti-halo paint coating samples, high-resistance anti-halo tape samples, and low-resistance anti-halo tape samples. The number of each type of test sample 3 is not less than 5, and they need to be dried at 60°C for 2 hours before testing to remove moisture.

[0037] The substrate of the test device plate electrode assembly 2 is an electrical mica plate (135 mm × 70 mm × 1 mm).

[0038] For the anti-halo coating samples, the anti-halo coating was uniformly applied to the surface of the mica plate using a roller coating method. The coating area was 90 mm × 25 mm, with the edge no less than 20 mm from the edge of the substrate. Two coats were applied. After the coating film cured, the thickness at five points below the knife electrode was measured according to GB / T13452.2, and the average value was taken. The thickness requirements were: 0.1 mm ± 0.02 mm for low-resistivity anti-halo coating and 0.15 mm ± 0.02 mm for high-resistivity anti-halo coating.

[0039] For anti-halo tape samples, cut a 90 mm long and 20-25 mm wide anti-halo tape, measure its average thickness according to GB / T 1310.2, and then use high-temperature resistant double-sided polyimide tape to fix it flat and neatly to the corresponding area on the surface of the mica board.

[0040] After the test sample 3 is fixed on the upper surface of the mica plate, a 135 mm × 70 mm copper foil or aluminum foil is pasted on the lower surface of the mica plate as a grounding electrode; the test sample 3 and the test device form a test assembly.

[0041] S2, Discharge Intensity Calibration A portion of the prepared sample was selected for preliminary experiments. The electrode electric field distribution curves under different gaps are shown below. Figure 5-7 As shown, simulation calculations revealed that the larger the discharge gap distance of the experimental device, the greater the distortion of the electric field distribution at both ends of the electrode. Simultaneously, experimental research showed that the larger the discharge gap, the more severe the corona damage to the anti-corona material areas at the two corners of the blade electrode. Therefore, considering the feasibility of the experimental operation, a gap of 2mm ± 0.1mm was chosen for the experiment. In a dark environment, the selected samples underwent preliminary experiments. After energizing the blade electrode 11 of the experimental device, a solar-blind ultraviolet imager (refer to DL / T298) was used to observe the discharge condition of the discharge gap. By adjusting the output voltage of the high-voltage power supply, a stable and relatively consistent discharge spot or ultraviolet signal was generated at the discharge gap of each type of sample (high resistance / low resistance). The voltage value corresponding to this state was recorded as the formal test voltage for that type of sample. This step ensured that different materials underwent aging under comparable discharge intensities.

[0042] S3, Accelerated Corona Aging Test The calibrated test components were placed entirely into a programmable oven. After closing the oven door, the temperature was raised to 120℃±2℃ at a rate not exceeding 5℃ / min and stabilized. Subsequently, the test voltage calibrated in step S2 was applied (e.g., approximately 5 kV for high-resistivity materials and approximately 4 kV for low-resistivity materials), and timing was started when stable gap discharge was observed. The aging cycles were set as follows: performance testing of high-resistivity materials was conducted at 0 h, 50 h, 100 h, 200 h, and 300 h; performance testing of low-resistivity materials was conducted at 0 h, 50 h, 100 h, 200 h, 250 h, and 300 h. At the end of each cycle, the samples were allowed to cool naturally to room temperature (23℃±2℃) inside the oven.

[0043] Corona resistance tests were conducted on different types of anti-corona tape and anti-corona paint samples using the gap discharge method. The test conditions for high-resistance anti-corona paint were: discharge gap distance 2 mm, voltage 5 kV, and temperature 120℃. The electrical performance after 50, 100, 200, and 300 hours of corona testing is shown in Tables 1, 2, and 3. Figures 8-10 As shown, white banded stripes appeared on the sample surface after gap discharge. The white marks became more pronounced and wider with prolonged corona treatment time, indicating increased surface damage. Under the same test voltage, the surface resistivity tended to decrease with prolonged corona treatment time, which was more pronounced at lower voltages. The resistance decrease was more significant for samples 1 and 2 compared to sample 3. After 50 hours of corona treatment, sample 1 showed a rapid increase in nonlinearity coefficient between 500-3000V and a rapid decrease between 3000-5000V, while the nonlinearity coefficient of sample 3 showed little change with corona treatment time. Sample 2, after 100 and 300 hours of corona treatment, showed ablation during resistance testing at a test voltage of 5000V, indicating a significant change in resistance characteristics after corona treatment and a poorer resistance to corona damage than high-resistance bands 1 and 3.

[0044]

[0045]

[0046]

[0047] S4. Performance Testing and Evaluation Immediately after each aging cycle, the following performance tests were performed on the test sample 3, which had been cooled to room temperature: Visual inspection: Visually observe and record the changes in the color and condition of the sample surface and the morphology of corona corrosion.

[0048] Surface resistivity testing: Measured according to GB / T 31838.3 using a two-electrode system (brass electrodes, 40 mm × 10 mm in size, 10 mm spacing, contact pressure 50 N). The test area should include the area of ​​action of the blade electrode. For low-resistivity materials, a digital multimeter is used; for high-resistivity materials, a megohmmeter is used at voltage levels ranging from 500 V to 5000 V.

[0049] Nonlinear coefficient calculation (for high-resistivity materials only): Based on the surface resistivity measured in step 2 at different voltages (e.g., 500 V, 1000 V, 2000 V, 3000 V, 4000 V, 5000 V), using the formula: ; The nonlinear coefficient β is calculated by fitting, where ρ_E is the surface resistivity under the corresponding electric field intensity E, and the formula is: ρ The surface resistivity is expressed as E when the electric field strength is E, and the unit is ohms (Ω). ρ 0 represents the inherent resistivity, measured in ohm-cm (Ω); E represents the electric field strength, measured in kilovolts per millimeter (kV / cm).

[0050] When the sample type is an anti-smudge coating sample, an adhesion test of the paint film is added to the sample.

[0051] When the sample type is a high-resistance anti-halo paint coating sample or a high-resistance anti-halo tape sample, the nonlinear coefficient β is calculated using the following formula: ; in, ρ a and ρ b Electric field strength E a and E b The surface resistivity below.

[0052] By systematically recording and analyzing the changes in the above performance parameters over aging time, the corona resistance and lifespan characteristics of different anti-corona materials can be scientifically evaluated.

[0053] The above description is merely a specific embodiment of the present invention. Any feature disclosed in this specification may be replaced by other equivalent or similar features unless otherwise specified. All features or steps in the disclosed methods or processes may be combined in any way, except for mutually exclusive features and / or steps.

Claims

1. A testing device for the corona resistance performance of motor anti-corona materials, characterized in that, The device includes a plate electrode assembly (2) and a blade electrode (1). The plate electrode assembly (2) is made of a mica substrate that is used to support the anti-corona material test sample and is insulated. A grounding electrode is fixed on the lower surface of the plate electrode assembly (2). The blade electrode (1) has a straight blade (11) at the bottom. The length of the straight blade (11) is 50 mm ± 0.1 mm, and the main curvature radius of its cross-sectional profile is 0.22 mm ± 0.008 mm. The corners of the straight blade (11) at both ends along the length direction have a rounded diameter of 3 mm ± 0.2 mm. The straight blade (11) is formed by the intersection of two oblique sides, and the blade angle is 53.14°. The blade electrode (1) is suspended directly above the plate electrode assembly (2). During the test, a uniform discharge gap is formed between the straight blade (11) of the blade electrode (1) and the surface of the test sample that is attached to the upper surface of the plate electrode assembly (2). The spacing of the discharge gap is adjustable.

2. The corona resistance testing device for motor anti-corona materials according to claim 1, characterized in that, The blade electrode (1) is fixedly mounted on the support adjustment screw (44). The plate electrode assembly (2) is provided with gap adjustment plates (42) on both sides. The gap adjustment plates (42) have strip-shaped adjustment holes (43). The two ends of the support adjustment screw (44) are located in the strip-shaped adjustment holes (43) of the gap adjustment plates (42) on both sides and can move up and down in the vertical direction in the strip-shaped adjustment holes (43) to adjust the discharge gap.

3. The corona resistance testing device for motor anti-corona materials according to claim 2, characterized in that, Locking nuts are respectively fitted onto the threads at both ends of the support adjusting screw (44). After the end of the support adjusting screw (44) passes through the strip-shaped adjusting hole (43), it is locked and fixed on the gap adjusting plate (42) by the locking nuts.

4. A corona resistance testing system for motor anti-corona materials, characterized in that, The device includes a transformer and the corona resistance test device for motor anti-corona material as described in claim 1. The test device is fixedly installed on the installation platform (41), and the blade electrode (1) of the test device is connected to the transformer through a wire.

5. The corona resistance test system for motor anti-corona materials according to claim 4, characterized in that, Multiple rows of motor anti-corona material corona resistance test units are fixedly installed on the installation platform (41). Each row of motor anti-corona material corona resistance test units consists of multiple corona resistance test devices arranged in sequence. The discharge gap between the test devices in the same row and the surface of the test sample is the same.

6. The corona resistance test system for motor anti-corona materials according to claim 5, characterized in that, Each column of motor anti-corona material corona resistance test unit has a gap adjustment plate (42) at both ends. The gap adjustment plate (42) has a strip adjustment hole (43). The blade electrode (1) in the same column of test device is connected in series by the support adjustment screw (42) into a whole. The two ends of the support adjustment screw (44) are located in the strip adjustment hole (43) of the gap adjustment plate (42) at both ends and can move up and down in the vertical direction in the strip adjustment hole (43) to adjust the discharge gap of the column. The support adjustment screw (44) is connected to the transformer through the wire.

7. The corona resistance test system for motor anti-corona materials according to claim 5, characterized in that, The test apparatus located in the same column shall have a spacing of not less than 50 mm between the center lines of two adjacent blade electrodes (1).

8. A test method for the corona resistance performance of motor anti-corona materials, characterized in that, The test method is implemented using the corona resistance test apparatus described in any one of claims 1-3, and includes the following steps: Step S1: Apply the anti-corona paint to be tested evenly to the upper surface of the plate electrode assembly (2) to form a coating sample, or fix the anti-corona tape to be tested flatly to the upper surface of the plate electrode assembly (2) to form an anti-corona tape sample, and then set a grounding electrode on the lower surface of the plate electrode assembly (2). Step S2: Select a portion of each sample type as a sample, conduct a preliminary experiment using an ultraviolet imager, adjust the test voltage applied to the test device, observe and calibrate the discharge intensity of the discharge gap, and determine the voltage value corresponding to aging tests of various samples under the same discharge intensity. Step S3: Adjust the distance between the straight blade (11) of the blade electrode (1) and the surface of the remaining sample to the set discharge gap; then place the test device in a programmable temperature control oven, raise the temperature to 120°C and stabilize it, apply the corresponding test voltage calibrated in step S2, so that the discharge gap discharges stably, and start timing to carry out the aging test. Step S4: After each set aging cycle, remove the sample, cool it to room temperature, then perform a visual inspection and test the surface resistivity of the sample, record and analyze the performance changes with aging time.

9. The method for testing the corona resistance of an anti-corona material for motors according to claim 8, characterized in that, Two coats of the anti-halo paint to be tested were applied to the upper surface of the plate electrode assembly (2) to form the anti-halo paint coating sample; wherein, When the sample type is a low-resistivity anti-halo paint coating sample, the average thickness of the paint film after curing is 0.1mm ± 0.01mm; When the sample type is a high-resistance anti-halo paint coating sample, the average thickness of the paint film after curing is 0.15mm ± 0.01mm.

10. A method for testing the corona resistance performance of an anti-corona material for motors according to claim 8, characterized in that, The anti-sickness strip sample was fixed at both ends to the plate electrode assembly (2) using epoxy resin.

11. The method for testing the corona resistance of an anti-corona material for motors according to claim 8, characterized in that, In step S3, the heating rate and cooling rate of the oven do not exceed 1℃ / min.

12. The method for testing the corona resistance of an anti-corona material for motors according to claim 8, characterized in that, In step S4, when the sample type is an anti-splatter paint coating sample, the performance test of the paint film adhesion of the sample is also included. When the sample type is a high-resistance anti-halo paint coating sample or a high-resistance anti-halo tape sample, the nonlinear coefficient performance index of the sample is also calculated. The calculation method is as follows: ； in, ρ a and ρ b Electric field strength E a and E b The surface resistivity below.

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