Control method and system for improving partial discharge test qualified rate of metering transformer

Abstract

The invention discloses a control method and system for improving the qualified rate of a partial discharge test of a metering mutual inductor, and the method sequentially comprises the following steps: mutual inductor iron core detection, coil winding, coil drying, mold filling of a transformer body, mold preheating, vacuum pouring, primary curing, mold demolding, secondary curing, and predelivery test. And meanwhile, the qualified state of each step is monitored and recorded, source control and active prevention of insulation defects can be realized, and the partial discharge test qualification rate of the metering transformer is improved.

Description

Technical Field

[0001] This invention relates to the field of power, and specifically to a control method and system for improving the pass rate of partial discharge tests on metering transformers. Background Technology

[0002] As an indispensable key component in the power system, metering transformers are standard measuring instruments responsible for the accurate measurement of high voltage and high current. Their performance directly affects the accuracy of power energy metering. Partial discharge (PD) is an important indicator for evaluating the insulation condition of transformers. Tiny defects within the insulation can trigger partial discharge under a strong electric field. Although this discharge may not immediately lead to penetrating breakdown, the resulting thermal effects, chemical effects, and particle bombardment gradually erode the insulation material, causing the transformer's insulation performance to deteriorate. Ultimately, this can lead to transformer failure and even threaten the safety of the entire power grid. Therefore, rigorous partial discharge testing of metering transformers is a necessary step to ensure their quality and operational reliability.

[0003] However, current partial discharge testing of instrument transformers faces numerous challenges in achieving a "high pass rate" (meaning accurately determining whether the equipment is truly qualified, rather than simply pursuing a high pass rate). These challenges mainly stem from potential design and manufacturing defects in the transformers themselves, complex electromagnetic interference environments, and the limitations of existing testing methods in terms of sensitivity and anti-interference capabilities. This not only increases production costs (including rework and scrapping) but may also lead to the commissioning of potentially risky equipment due to missed detections. Summary of the Invention

[0004] (a) Purpose of the invention The purpose of this invention is to provide a control method and system for improving the pass rate of partial discharge tests of metering transformers. It aims to monitor the entire production process of metering transformers, record key data affecting the pass rate of partial discharge tests, achieve source control and proactive prevention of insulation defects, and improve the pass rate of partial discharge tests of metering transformers.

[0005] (II) Technical Solution To address the above problems, a first aspect of the present invention provides a control method for improving the pass rate of partial discharge tests on metering transformers, comprising the following steps: The first aspect of the present invention provides a control method for improving the pass rate of partial discharge tests on metering transformers, comprising the following steps: S1, Current transformer core testing, including: monitoring the insulation performance and electromagnetic performance of the core, and determining whether to enter the current transformer core testing data into the historical database based on the test results; S2. If the transformer core test data is entered into the historical database, the coil winding process is started. After the coil winding is completed, the coil error is detected. Based on the test results, it is determined whether to enter the error detection data into the historical database. S3. If the error detection data is entered into the historical database, the coil drying process is started. The moisture content, vacuum degree and temperature of the collected coil semi-finished product are dynamically corrected through the coil drying process. Based on the correction results, it is determined whether to enter the correction data into the historical database. S4. If the corrected data is entered into the historical database, the body molding process is started. The outline and position of the coil semi-finished product after winding are analyzed through the body molding process. At the same time, the position of the coil semi-finished product is dynamically corrected. Based on the corrected results, it is determined whether to enter the analysis data into the historical database. S5. If the analysis data is entered into the historical database, the mold preheating process is started. The mold temperature is collected and dynamically corrected through the mold preheating process. Based on the corrected result, it is determined whether to enter the temperature data into the historical database. S6. If the temperature data is entered into the historical database, the vacuum casting process is started. The vacuum pressure and vacuum temperature are collected and dynamically corrected through the vacuum casting process. Based on the corrected results, it is determined whether to enter the data corresponding to the vacuum pressure and vacuum temperature into the historical database. S7. If the data corresponding to vacuum pressure and vacuum temperature are entered into the historical database, then a first curing process is started. The temperature of the mold is collected and dynamically corrected through the first curing process. Based on the corrected result, it is determined whether to enter the temperature of the mold into the historical database. S8. If the mold temperature is recorded in the historical database, the mold demolding process is started. The mold demolding process is used to extract and analyze the contour of the mold surface. Based on the extraction and analysis results, it is determined whether to record the contour analysis data into the historical database. S9. If the contour analysis data is entered into the historical database, the secondary curing process is started. The temperature of the mold surface is collected and dynamically corrected through the secondary curing process. Based on the corrected result, it is determined whether to enter the temperature data of the mold surface into the historical database. S10. If the temperature data of the mold surface is entered into the historical database, the factory test is started. The finished metering transformer is tested through the factory test, and the qualified test data is entered into the historical database.

[0006] Furthermore, the current transformer core detection includes the following steps: Start the iron core monitoring equipment; The insulation and electromagnetic performance of the transformer core are monitored using core monitoring equipment. The test results are then judged to determine whether they are qualified. If they are qualified, the transformer core test data is entered into the historical database. Each core corresponds to a unique ID. The insulation performance monitoring includes interlayer insulation resistance, power frequency withstand voltage and partial discharge. The electromagnetic performance monitoring includes excitation characteristics, remanence coefficient and magnetic flux density.

[0007] Furthermore, the process of initiating the coil winding process, performing coil error detection after the coil winding is completed, and determining whether to record the error detection data into the historical database based on the detection results includes the following steps: Start the winding monitoring equipment; The characteristics of the current transformer are detected by the coil winding process using winding monitoring equipment. The system determines whether the transformer is qualified. If it is qualified, the test data is entered into the historical database. The transformer characteristic test includes error, polarity test and volt-ampere characteristic test. If it is unqualified, the coil winding scheme is corrected.

[0008] Furthermore, the coil drying process includes the following steps: Start the coil drying monitoring equipment; The moisture content, vacuum level, and temperature of the coil semi-finished product are collected in real time using coil drying monitoring equipment; The collected moisture content, vacuum degree and temperature are dynamically corrected, and the correction results determine whether to enter the corrected data into the historical database. During the dynamic correction process, the moisture prediction deviation of the control coil semi-finished product is <5%.

[0009] Furthermore, the body assembly process includes the following steps: Starter body mold monitoring equipment; The outline and position of the wound coil semi-finished product are analyzed using the mold mounting monitoring equipment. Construct a three-dimensional insulation distance model of the coil body and perform threshold identification: if the maximum distance in the three-dimensional insulation distance model of the coil body is less than or equal to a set threshold, dynamically correct the position of the coil semi-finished product, and determine whether to enter the analysis data into the historical database based on the correction result.

[0010] A second aspect of the present invention provides a control system for improving the pass rate of partial discharge tests of metering transformers, comprising a transformer core monitoring module, a coil winding monitoring module, a coil drying monitoring module, a transformer body molding module, a mold preheating module, a vacuum casting module, a primary curing module, a mold demolding module, a secondary curing module, and a factory test module. Each module operates according to the following steps: Current transformer core monitoring module: used to monitor the insulation and electromagnetic performance of the core, and to determine whether to enter the current transformer core test data into the historical database based on the test results; If the transformer core detection data is entered into the historical database, the coil winding monitoring module is activated. The winding error is detected through the coil winding monitoring module, and the error detection data is entered into the historical database based on the detection results. If the error detection data is entered into the historical database, the coil drying monitoring module is activated. The coil drying monitoring module dynamically corrects the collected moisture content, vacuum degree and temperature of the coil semi-finished product. Based on the correction results, it is determined whether to enter the correction data into the historical database. If the corrected data is entered into the historical database, the body molding module is activated. The body molding module performs contour and position analysis on the coil semi-finished product after winding, and dynamically corrects the position of the coil semi-finished product. Based on the corrected results, it is determined whether to enter the analysis data into the historical database. If the analysis data is entered into the historical database, the mold preheating module is activated. The mold temperature is collected and dynamically corrected through the mold preheating module. Based on the corrected result, it is determined whether to enter the temperature data into the historical database. If the temperature data is entered into the historical database, the vacuum casting module is activated. The vacuum casting module collects vacuum pressure and vacuum temperature and performs dynamic correction. Based on the correction results, it is determined whether to enter the data corresponding to vacuum pressure and vacuum temperature into the historical database. If the data corresponding to vacuum pressure and vacuum temperature are entered into the historical database, the primary curing module is activated. The temperature of the mold is collected and dynamically corrected through the primary curing module. Based on the corrected result, it is determined whether to enter the temperature of the mold into the historical database. If the mold temperature is entered into the historical database, the mold demolding module is activated. This module extracts and analyzes the contour of the mold surface, and based on the analysis results, determines whether to enter the contour analysis data into the historical database. If the contour analysis data is entered into the historical database, the secondary curing module is activated. The temperature of the mold surface is collected and dynamically corrected through the secondary curing module. Based on the corrected result, it is determined whether to enter the temperature data of the mold surface into the historical database. If the temperature of the mold surface is entered into the historical database, the factory test module is activated. The finished metering transformer is tested through the factory test module, and the qualified test data is entered into the historical database.

[0011] Furthermore, the current transformer core monitoring module is used for: Start the iron core monitoring equipment; The insulation and electromagnetic properties of the iron core are monitored using iron core monitoring equipment. Determine whether the test results are qualified. If qualified, the test data of the transformer core is entered into the historical database. Each core corresponds to a unique ID. The insulation performance monitoring includes interlayer insulation resistance, power frequency withstand voltage and partial discharge. The electromagnetic performance monitoring includes excitation characteristics, remanence coefficient and magnetic flux density.

[0012] Furthermore, the coil winding module is used for: Start the winding monitoring equipment; The characteristics of the current transformer are detected by the coil winding process using winding monitoring equipment. The system determines whether the transformer is qualified. If it is qualified, the test data is entered into the historical database. The transformer characteristic test includes error, polarity test and volt-ampere characteristic test. If it is unqualified, the coil winding scheme is corrected in time.

[0013] Furthermore, the coil drying module is used for: Start the coil drying monitoring equipment; The moisture content, vacuum level, and temperature of the coil semi-finished product are collected in real time using coil drying monitoring equipment; The collected moisture content, vacuum degree and temperature are dynamically corrected. The correction results are compared with the standard process database to determine whether to enter the corrected data into the historical database. During the dynamic correction process, the moisture prediction deviation of the control coil semi-finished product is <5%.

[0014] Furthermore, the body molding module is used for: Starter body mold monitoring equipment; The outline and position of the wound coil semi-finished product are analyzed using the mold mounting monitoring equipment. A three-dimensional insulation distance model of the coil body is constructed, and threshold identification is performed: if the maximum distance in the three-dimensional insulation distance model is less than or equal to a set threshold, the position of the coil semi-finished product is dynamically corrected, and the corrected result is compared with the standard process database to determine whether the analysis data should be entered into the historical database. (III) Beneficial Effects The above-mentioned technical solution of the present invention has the following beneficial technical effects: The present invention provides a control method and system for improving the pass rate of partial discharge test of metering transformers. The method includes the following steps in sequence: transformer core inspection → coil winding → coil drying → transformer body molding → mold preheating → vacuum casting → primary curing → mold demolding → secondary curing → factory test. This application aims to monitor the production process of metering transformers throughout the entire process, record key data affecting the pass rate of partial discharge test, and if the metering transformer fails the partial discharge test, the key data of the failure can be found through full-process data traceability, the process flow can be improved, the core process can be standardized, and a data-driven closed-loop control and traceability mechanism can be constructed to achieve source control and proactive prevention of insulation defects, thereby improving the pass rate of partial discharge test of metering transformers. Attached Figure Description

[0015] Figure 1 This is a flowchart of the control method for improving the pass rate of partial discharge test of metering transformers according to the present invention; Figure 2 This is a schematic diagram of the control system of the present invention for improving the pass rate of partial discharge test of metering transformers. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0017] like Figure 1 As shown, the first aspect of the present invention provides a control method for improving the pass rate of partial discharge test of metering transformers, including the following steps: S1, transformer core detection, including: monitoring the insulation performance and electromagnetic performance of the core, and determining whether to enter the transformer core detection data into the historical database based on the detection results; S2. If the transformer core test data is entered into the historical database, the coil winding process is started. After the coil winding is completed, the coil error is detected. Based on the test results, it is determined whether to enter the error detection data into the historical database. S3. If the error detection data is entered into the historical database, the coil drying process is started. The collected moisture content, vacuum degree and temperature of the coil are dynamically corrected through the coil drying process. The correction results are compared with the standard process database to determine whether to enter the corrected data into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as moisture content / vacuum degree / temperature that have been accumulated and stored in the past during the execution of the coil drying process and can be referenced and executed to complete the coil drying with high quality. S4. If the corrected data is entered into the historical database, the body molding process is started. The contour and position of the coil semi-finished product after winding are analyzed through the body molding process, and the position of the coil semi-finished product is dynamically corrected. Based on the corrected results, it is determined whether to enter the analysis data into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as the distance between the coil semi-finished product and the mold that are accumulated and stored in the past during the execution of the body molding process. S5. If the analysis data is entered into the historical database, the mold preheating process is started. The mold temperature is collected through the mold preheating process and the heating equipment is controlled to adjust the dynamic correction temperature. The corrected result is compared with the standard process database to determine whether the temperature data is entered into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as mold temperature that have been accumulated and stored in the past during the execution of the mold preheating process and can be referenced and executed to complete the mold preheating (mold temperature) with high quality. S6. If the temperature data is entered into the historical database, the vacuum casting process is started. The vacuum casting equipment collects the vacuum pressure and vacuum temperature and controls the vacuum equipment and heating equipment to make dynamic corrections. Based on the correction results, it is determined whether to enter the data corresponding to the vacuum pressure and vacuum temperature into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as vacuum pressure and temperature that have been accumulated and stored in the past during the execution of the vacuum casting process and can be referenced and executed to complete vacuum casting with high quality. S7. If the data corresponding to vacuum pressure and vacuum temperature are entered into the historical database, then the first curing process is started. The temperature of the mold is collected through the first curing process and the heating equipment is controlled to adjust the dynamic correction temperature. The corrected result is compared with the standard process database to determine whether the temperature of the mold is entered into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as mold temperature that have been accumulated and stored in the past during the execution of the first curing process and can be referenced and executed to complete the first curing with high quality. S8. If the mold temperature is recorded in the historical database, the mold demolding process is started. The mold demolding process is used to extract and analyze the contour of the mold surface. The extraction and analysis results are compared with the standard process database to determine whether to record the contour analysis data into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as mold contour data that have been accumulated and stored in the past during the execution of the mold demolding process and can be referenced and executed to complete the mold demolding with high quality. S9. If the contour analysis data is entered into the historical database, the secondary curing process is started. The temperature of the surface of the finished transformer is collected through the secondary curing process and the heating equipment is controlled to adjust the dynamic correction temperature. The corrected result is compared with the standard process database to determine whether the mold temperature data is entered into the historical database. The "standard process database" in this step refers to the set of historical data related to key process parameters such as the surface temperature of the transformer that have been accumulated and stored in the past during the execution of the secondary curing process and can be referenced and executed to complete the secondary curing with high quality. S10. If the temperature data of the instrument transformer surface is entered into the historical database, the factory test is initiated. The finished metering instrument transformer is tested through the factory test, and the qualified test data is entered into the standard process database. Unqualified products are systematically tested and analyzed. The process problems are located by combining structural characteristics, historical data and multi-dimensional testing methods. The relevant process parameters in the standard process database are removed based on the process problems.

[0018] The steps are explained in detail below: The transformer core testing includes the following steps: starting the core monitoring equipment → using the core monitoring equipment to monitor the insulation performance and electromagnetic performance of the core → comparing the monitoring results with the standard process database to determine whether the test results meet the requirements → if qualified → recording the transformer core test data into the historical database. The structure and material performance of the core determine the error accuracy of the transformer. Core testing includes monitoring the insulation performance and electromagnetic performance of the transformer core. If unqualified, it enters the unqualified component buffer area. Each core corresponds to a unique ID. Insulation performance monitoring includes interlayer insulation resistance, power frequency withstand voltage, and partial discharge quantity. The data for interlayer insulation resistance, power frequency withstand voltage, and partial discharge quantity of each core are recorded. Electromagnetic performance monitoring includes excitation characteristics, remanence coefficient, and magnetic flux density. The data for excitation characteristics, remanence coefficient, and magnetic flux density of each core are recorded.

[0019] The coil winding process includes the following steps: starting the winding monitoring equipment → using the winding monitoring equipment to perform transformer characteristic testing on the winding process → comparing the test results with the standard process database to determine whether the requirements are met → if qualified → error detection data is entered into the historical database; if unqualified, it is entered into the unqualified component cache area. The transformer characteristic testing includes error, polarity test, and volt-ampere characteristic test. The coil winding process uses error, volt-ampere characteristic, and polarity test equipment to perform error, volt-ampere characteristic, and polarity tests on the wound coil semi-finished products. The test results for each coil semi-finished product are recorded and saved for real-time retrieval.

[0020] The coil drying process includes the following steps: starting the coil drying monitoring equipment → real-time acquisition of coil moisture content, vacuum level, and temperature → dynamic parameter correction → comparing the corrected results with the standard process database to determine if the requirements are met → if qualified → recording the coil moisture content and vacuum level into the historical database; if unqualified, entering the unqualified parts buffer area (unqualified products in subsequent steps will all enter the unqualified parts buffer area). In this step, the predicted deviation of coil moisture content is controlled to be <5% by dynamically correcting the drying kinetic parameters. During the coil drying process, a microwave moisture sensor is used to monitor the water molecule content of the transformer coil in real time, a vacuum gauge installed in the eddy current dead zone area of ​​the drying tank is used to measure the vacuum level in real time, and a distributed platinum resistance PT1000 temperature sensor is used to monitor the coil temperature in real time.

[0021] The assembly of the transformer body includes the following steps: activating the transformer body assembly monitoring equipment → sequentially extracting and analyzing the contour positions of the wound coils → constructing a three-dimensional insulation distance model → dynamically adjusting the threshold → comparing the corrected results with the standard process database to determine if the requirements are met → if qualified → recording the distance data between the transformer body and the mold into the historical database. In the constructed three-dimensional insulation distance model, the distance between the transformer body and the mold is ≤5mm. The transformer body assembly uses a high-resolution camera and 4D millimeter-wave radar to capture the external structure of the transformer body, accurately identifying the contours, positions, and surface conditions of insulating components, and analyzing the static insulation distance between components in real time to ensure that the assembly conforms to design specifications and avoids abnormal insulation distances during assembly. By fusing multi-dimensional data from images and radar information, a three-dimensional insulation distance model of the transformer body is constructed to identify millimeter-level distance deviations. Once a distance exceeding the threshold is detected, an audible and visual alarm is immediately triggered, and the abnormal position is recorded until the distance meets the requirements.

[0022] Mold preheating includes the following steps: activating the mold preheating monitoring equipment → acquiring mold temperature using a non-contact thermal imaging device → dynamic temperature correction → comparing the corrected results with the standard process database to determine if requirements are met → if qualified → recording the mold temperature into the historical database. This mold preheating process acquires comprehensive mold temperature data, records the temperature of each mold, displays the temperature change trend of different areas, and monitors temperature and historical temperature curves in real time, facilitating detailed analysis of the mold preheating process. When an abnormal mold temperature is detected, the system will issue an alarm.

[0023] Vacuum casting includes the following steps: starting the vacuum casting monitoring equipment → collecting vacuum pressure and temperature data in the casting tank → dynamically correcting the vacuum level and temperature → comparing the corrected results with the standard process database to determine if the requirements are met → if qualified → entering the temperature and vacuum pressure data into the historical database. Vacuum casting requires real-time monitoring of process parameters such as mixing temperature, mixing time, vacuum level in the mixing tank, temperature in the casting tank, vacuum level in the casting tank, pre-vacuuming time in the casting tank, casting time, and vacuum holding time. Vacuum casting is used to better remove small molecule gases generated during the raw material reaction process, avoid the formation of bubbles in the product, and improve the pass rate of partial release tests.

[0024] The primary curing process includes the following steps: activating the primary curing monitoring equipment → acquiring mold temperature using a non-contact thermal imaging device → dynamic temperature correction → comparing the corrected results with the standard process database to determine if requirements are met → if qualified → recording the mold temperature into the historical database. During the primary curing process, the non-contact thermal imaging device scans the temperature distribution on the mold surface and inside the casting in real time, indirectly inferring the resin curing reaction progress and avoiding localized overheating or insufficient curing. The resin releases heat during curing, and thermal imaging captures temperature peaks. By comparing the real-time temperature curve with the ideal curing curve, it is determined whether the reaction is sufficient. Simultaneously, closed-loop control is achieved by dynamically adjusting the thermal imaging data, heating power, and fan speed.

[0025] The mold demolding process includes the following steps: activating the mold demolding monitoring equipment → using a high-resolution industrial camera to extract the contour from optical point cloud data → determining surface flow marks, wrinkles, demolding residue, etc. → alarm / compensation correction → comparing the corrected results with the standard process database to determine if requirements are met → if qualified → entering the contour data into the historical database. The mold demolding process utilizes a high-resolution industrial camera to capture micron-level anomalies, achieving precise detection of defects such as surface flow marks, wrinkles, and demolding residue.

[0026] The secondary curing process includes the following steps: starting the secondary curing monitoring equipment → collecting the temperature of the finished instrument transformer using a non-contact thermal imaging device → dynamic temperature correction → comparing the corrected results with the standard process database to determine if the requirements are met → if qualified → recording the finished instrument transformer temperature data into the historical database. The secondary curing process can eliminate internal stress, improve mechanical strength and partial discharge levels. Through non-contact thermal imaging, the temperature distribution on the mold surface and inside the casting is scanned in real time, indirectly inferring the progress of the resin curing reaction and avoiding localized overheating or insufficient curing. The resin releases heat during curing, and thermal imaging can capture temperature peaks. By comparing the real-time temperature curve with the ideal curing curve, the sufficiency of the reaction is determined. Closed-loop control is achieved by dynamically adjusting the thermal imaging data along with heating power and fan speed.

[0027] The factory test includes the following steps: starting the factory test monitoring equipment → entering the insulation resistance measurement mode (power frequency withstand voltage test mode, secondary winding turn-to-turn insulation test mode, error test mode under reference conditions, magnetic saturation margin test mode, partial discharge measurement mode, excitation characteristic test mode, error test mode under extreme temperature conditions, and electronic tag test mode) → judging whether the test results meet the requirements based on the set value accuracy → if qualified → entering the factory test data into the historical database. The factory test monitoring uses the factory test equipment to perform visual inspection, insulation resistance measurement, power frequency withstand voltage test, secondary winding turn-to-turn insulation test, error test under reference conditions, magnetic saturation margin test, partial discharge measurement, excitation characteristic test, error test under extreme temperature conditions, and electronic tag test on each finished instrument transformer. The test results for each finished instrument transformer are recorded and saved for real-time retrieval.

[0028] like Figure 2 As shown, a second aspect of the present invention provides a control system for improving the pass rate of partial discharge tests of metering transformers, including a transformer core monitoring module 21, a coil winding module 22, a coil drying monitoring module 23, a transformer body molding module 24, a mold preheating module 25, a vacuum casting module 26, a primary curing module 27, a mold demolding module 28, a secondary curing module 29, and a factory test module 30. Each module should be run according to the following steps: Transformer core monitoring module 21: used to monitor the insulation performance and electromagnetic performance of the core, and to determine whether to enter the transformer core test data into the historical database based on the test results; If the test data of the transformer core is entered into the historical database, the winding monitoring module 22 is started. The winding monitoring module performs performance testing on the coil semi-finished product, and determines whether to enter the test data into the historical database based on the test results. If the coil performance test data is entered into the historical database, the coil drying monitoring module 23 is activated. The coil drying monitoring module detects the moisture content, vacuum degree and temperature of the coil semi-finished product. Based on the analysis results, it is determined whether to enter the coil moisture content, vacuum degree and temperature data into the historical database. If the coil moisture content, vacuum degree and temperature data are entered into the historical database, the body molding module 24 is activated. The body molding process is used to analyze the outline and position of the coil semi-finished product after winding. The corrected position data is compared with the standard process database to determine whether to enter the analysis data into the historical database. If the location data is entered into the historical database, the mold preheating module 25 is activated. The mold temperature is collected through the mold preheating module, and the mold temperature data is entered into the historical database based on the collection results. If the temperature data of mold preheating is entered into the historical database, the vacuum casting module 26 is started. The vacuum casting module collects vacuum pressure and vacuum temperature, and determines whether to enter the data corresponding to vacuum pressure and vacuum temperature into the historical database based on the collection results. If the data corresponding to vacuum pressure and vacuum temperature are entered into the historical database, the primary curing module 27 is activated. The temperature of the primary curing monitoring device is collected through the primary curing module, and the mold temperature collected by the primary curing monitoring device is entered into the historical database based on the collection results. If the mold temperature collected by the primary curing monitoring device is entered into the historical database, the mold demolding module 28 is activated. The mold demolding module extracts and analyzes the contour of the mold surface, and determines whether to enter the analysis data into the historical database based on the mold surface analysis results. If the mold surface analysis data is entered into the historical database, the secondary curing module 29 is activated. The temperature of the mold surface is collected and dynamically compensated through the secondary curing module. Based on the collection results, it is determined whether to enter the temperature data into the historical database. If the temperature data is entered into the historical database, the factory test module 30 is activated to test the finished metering transformer and enter the qualified test data into the historical database.

[0029] This system utilizes data collected by monitoring equipment to perform full-process monitoring of metering transformers. Each module is responsible for storing, processing, and analyzing the monitored data to obtain the real-time monitored process parameter V. R Once a deviation value V occurs D The absolute value of the measured value and the reference value exceeds the allowable error V. AE Immediately correct or suspend the transfer of the product with that number to the next process flow, and monitor the process data V collected by each module. R Compared with the benchmark value V in the standard process databaseS A comparison is performed to confirm whether the process data meets the requirements. If a metering transformer fails the partial discharge test during the factory testing phase, a full-process process traceability is immediately performed on that transformer. The process data monitored from each module is compared again with the standard process database to identify and confirm the specific reasons for the partial discharge test failure. Feedback is provided on the issues of the non-conforming products, and the corresponding processes are optimized and synchronized to the standard process database, thereby continuously improving the product partial discharge test pass rate. The functions of each module are described below: The current transformer core monitoring module is used for: starting the core monitoring equipment → using the core monitoring equipment to monitor the insulation and electromagnetic performance of the core → comparing the monitoring results with the standard process database to determine whether the test results meet the requirements → if qualified → recording the current transformer core test data into the historical database; if unqualified, entering the unqualified component cache area. Each core corresponds to a unique ID. The insulation performance monitoring includes interlayer insulation resistance, power frequency withstand voltage, and partial discharge quantity. The electromagnetic performance monitoring includes excitation characteristics, remanence coefficient, and magnetic flux density. The structure and material performance of the core determine the error accuracy of the current transformer. The unique ID binds to each core. The core monitoring module is capable of monitoring the insulation and electromagnetic performance of each current transformer core, recording the core model, supplier, interlayer insulation resistance, power frequency withstand voltage, partial discharge quantity data, excitation characteristics, remanence coefficient, and magnetic flux density of each unique ID core, and establishing a full life cycle archive database for each core.

[0030] The coil winding module is used for: starting the winding monitoring equipment → using the winding monitoring equipment to detect the transformer characteristics of the winding process → comparing the detection results with the standard process database to determine whether the requirements are met → if qualified → entering the error detection data into the historical database, wherein the transformer characteristic detection includes error, polarity test and volt-ampere characteristic detection.

[0031] The coil drying module is used for: starting the coil drying monitoring equipment → real-time acquisition of coil moisture content, vacuum degree, and temperature → dynamic parameter correction → comparing the corrected results with the standard process database to determine if the requirements are met → if qualified → recording the coil moisture content and vacuum degree into the historical database. In this step, the predicted deviation of coil moisture content is controlled to be <5% by dynamically correcting the drying kinetic parameters. The coil drying module is located inside the vacuum drying equipment for semi-finished coils and belongs to the vacuum drying process for current transformer coils. A microwave moisture sensor is used to monitor the water molecule content of the current transformer coil in real time, a vacuum gauge installed in the eddy current dead zone area of ​​the drying tank is used to measure the vacuum degree in real time, and a distributed platinum resistance PT1000 temperature sensor is used to monitor the temperature in real time. The water molecule content is regulated by precisely controlling the drying temperature, humidity, time, and vacuum degree to ensure that the moisture in the coil insulation material is fully evaporated and well cured, avoiding residual air bubbles or moisture that may cause partial discharge failure. Based on the real-time acquisition of the temperature-vacuum-moisture three-dimensional data flow, the drying kinetic parameters are dynamically corrected, and the predicted deviation of coil moisture content is <5%.

[0032] The body assembly module is used for: starting the body assembly monitoring equipment → sequentially extracting and analyzing the contour positions of the wound coils → constructing a three-dimensional insulation distance model → dynamically adjusting the threshold → comparing the corrected results with the standard process database to determine if the requirements are met → if qualified → recording the distance data between the body and the mold into the historical database. In constructing the three-dimensional insulation distance model, the distance between the body and the mold is ≤5mm. The body assembly module is used in the body assembly process. It captures the body's external structure using a high-resolution industrial camera and 4D millimeter-wave radar, accurately identifying the contours, positions, and surface conditions of insulating components, and analyzing the static insulation distance between components in real time to ensure that the assembly conforms to design specifications and avoids abnormal insulation distances during assembly. By fusing multi-dimensional data from images and radar information, a three-dimensional insulation distance model of the body is constructed to identify millimeter-level distance deviations. Once a distance exceeding 5mm is detected, an audible and visual alarm is immediately triggered, and the abnormal position is recorded until the distance meets the requirements.

[0033] The mold preheating module is part of the mold preheating process. It acquires comprehensive mold temperature data in real time using a non-contact thermal imaging device, recording the temperature of each mold element. By modeling the mold and selecting different temperature points, it monitors the temperature change trends of each sampling area in real time, plotting historical temperature curves for detailed analysis of the mold preheating process. When an abnormal mold temperature is detected, the module dynamically compensates for the temperature by controlling the heating equipment to prevent micro-cracks caused by the abnormal temperature. The process is as follows: Start mold preheating monitoring device → Non-contact thermal imaging device acquires mold temperature → Dynamic temperature correction → Compare the corrected results with the standard process database to determine if requirements are met → If qualified → Enter the mold temperature into the historical database.

[0034] The vacuum casting module pertains to the vacuum casting process. This module is used for real-time monitoring of process parameters such as mixing temperature, mixing time, vacuum level in the mixing tank, temperature and vacuum level in the casting tank, pre-vacuuming time, casting time, and vacuum holding time. Vacuum casting is used to better remove small molecule gases generated during the raw material reaction, preventing air bubbles in the product and improving the partial release test pass rate. The vacuum casting module is used for: starting the vacuum casting monitoring equipment → acquiring vacuum pressure and temperature in the casting tank → dynamically correcting vacuum level and temperature → comparing the corrected results with the standard process database to determine if requirements are met → if qualified → entering temperature and vacuum pressure into the historical database.

[0035] The primary curing module is part of a primary curing process. Using non-contact thermal imaging equipment, it scans the temperature distribution on the mold surface and inside the casting in real time, indirectly inferring the progress of the resin curing reaction. This avoids localized overheating or insufficient curing. The resin releases heat during curing, and thermal imaging captures temperature peaks. By comparing the real-time temperature curve with the ideal curing curve, it determines whether the reaction is sufficient. Thermal imaging data, along with heating power and fan speed, are dynamically adjusted to precisely control the temperature gradient, heating / cooling rates, and holding time during the curing process, achieving closed-loop control. The primary curing module is used for: starting the primary curing monitoring equipment → acquiring the mold temperature using non-contact thermal imaging equipment → dynamic temperature correction → comparing the corrected results with a standard process database to determine if requirements are met → if qualified → recording the mold temperature into the historical database.

[0036] The mold release module pertains to the mold release process. It uses a high-resolution industrial camera to capture micron-level anomalies, enabling precise detection of defects such as surface flow marks, wrinkles, and release residue. The module is used for: activating the mold release monitoring equipment → contour extraction using optical point cloud data by the high-resolution industrial camera → determination of surface flow marks, wrinkles, and release residue → alarm / compensation correction → comparison of the corrected results with the standard process database to determine if requirements are met → if qualified → entry of contour data into the historical database.

[0037] The secondary curing module belongs to the secondary curing process. Secondary curing can eliminate internal stress, improve mechanical strength and partial discharge level. Using non-contact thermal imaging equipment, it scans the temperature distribution of the mold surface and internal casting in real time, indirectly inferring the resin curing reaction progress and avoiding localized overheating or insufficient curing. The resin releases heat during curing, and thermal imaging can capture temperature peaks. By comparing the real-time temperature curve with the ideal curing curve, it can determine whether the reaction is sufficient. Thermal imaging data, heating power, and fan speed are dynamically adjusted to achieve closed-loop control. The secondary curing module is used for: starting the secondary curing monitoring equipment → collecting the temperature of the finished transformer using non-contact thermal imaging equipment → dynamic temperature correction → comparing the corrected results with the standard process database to determine if requirements are met → if qualified → entering the finished transformer temperature data into the historical database.

[0038] The factory test module is located during the factory test process. It uses factory test equipment to perform visual inspection, insulation resistance measurement, power frequency withstand voltage test, secondary winding turn-to-turn insulation test, error test under reference conditions, magnetic saturation margin test, partial discharge measurement, excitation characteristic test, error test under extreme temperature conditions, and electronic tag test on each finished instrument transformer. The test results for each finished instrument transformer are recorded and saved for real-time retrieval. The factory test module is used for: starting the factory test monitoring equipment → entering insulation resistance measurement mode (power frequency withstand voltage test mode, secondary winding turn-to-turn insulation test mode, error test under reference conditions mode, magnetic saturation margin test mode, partial discharge measurement mode, excitation characteristic test mode, error test under extreme temperature conditions mode, and electronic tag test mode) → judging whether the test results meet the requirements based on the set value accuracy → if qualified → entering the factory test data into the historical database.

[0039] It should be noted that the real-time monitoring data of all the above modules, including interlayer insulation resistance, power frequency withstand voltage, partial discharge, excitation characteristics, remanence coefficient, magnetic flux density, error, volt-ampere characteristics, polarity test, temperature, vacuum degree, moisture content, and static insulation distance between components, are all collected and processed by monitoring equipment. (See formula...) As shown, all process parameters monitored in real time can be obtained using V. R This indicates that all reference values ​​in the standard process database can be used with V. S This indicates that the absolute values ​​of both the measured and benchmark values ​​can be represented using V. D This indicates that the allowable error of the monitoring system can be expressed using V. AE express.

[0040] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of the present invention and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of the present invention should be included within the protection scope of the present invention. The present invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the functions specified in one or more boxes. The steps in the method of this embodiment can be adjusted, merged, and deleted according to actual needs. The modules in the system of this embodiment can be merged, divided, and deleted according to actual needs.

Claims

1. A control method for improving the pass rate of partial discharge tests on metering transformers, characterized in that, Includes the following steps: S1, Current transformer core testing, including: monitoring the insulation performance and electromagnetic performance of the core, and determining whether to enter the current transformer core testing data into the historical database based on the test results; S2. If the transformer core test data is entered into the historical database, the coil winding process is started. After the coil winding is completed, the coil error is detected. Based on the test results, it is determined whether to enter the error detection data into the historical database. S3. If the error detection data is entered into the historical database, the coil drying process is started. The moisture content, vacuum degree and temperature of the collected coil semi-finished product are dynamically corrected through the coil drying process. Based on the correction results, it is determined whether to enter the correction data into the historical database. S4. If the corrected data is entered into the historical database, the body molding process is started. The outline and position of the coil semi-finished product after winding are analyzed through the body molding process. At the same time, the position of the coil semi-finished product is dynamically corrected. Based on the corrected results, it is determined whether to enter the analysis data into the historical database. S5. If the analysis data is entered into the historical database, the mold preheating process is started. The mold temperature is collected and dynamically corrected through the mold preheating process. Based on the corrected result, it is determined whether to enter the temperature data into the historical database. S6. If the temperature data is entered into the historical database, the vacuum casting process is started. The vacuum pressure and vacuum temperature are collected and dynamically corrected through the vacuum casting process. Based on the corrected results, it is determined whether to enter the data corresponding to the vacuum pressure and vacuum temperature into the historical database. S7. If the data corresponding to vacuum pressure and vacuum temperature are entered into the historical database, then a first curing process is started. The temperature of the mold is collected and dynamically corrected through the first curing process. Based on the corrected result, it is determined whether to enter the temperature of the mold into the historical database. S8. If the mold temperature is recorded in the historical database, the mold demolding process is started. The mold demolding process is used to extract and analyze the contour of the mold surface. Based on the extraction and analysis results, it is determined whether to record the contour analysis data into the historical database. S9. If the contour analysis data is entered into the historical database, the secondary curing process is started. The temperature of the mold surface is collected and dynamically corrected through the secondary curing process. Based on the corrected result, it is determined whether to enter the temperature data of the mold surface into the historical database. S10. If the temperature data of the mold surface is entered into the historical database, the factory test is started. The finished metering transformer is tested through the factory test, and the qualified test data is entered into the historical database.

2. The control method for improving the pass rate of partial discharge test of metering transformers according to claim 1, characterized in that, The current transformer core detection includes the following steps: Start the iron core monitoring equipment; The insulation and electromagnetic performance of the transformer core are monitored using core monitoring equipment. The test results are then judged to determine whether they are qualified. If they are qualified, the transformer core test data is entered into the historical database. Each core corresponds to a unique ID. The insulation performance monitoring includes interlayer insulation resistance, power frequency withstand voltage and partial discharge. The electromagnetic performance monitoring includes excitation characteristics, remanence coefficient and magnetic flux density.

3. The control method for improving the pass rate of partial discharge tests of metering transformers according to claim 1, characterized in that, The process of starting the coil winding process, followed by coil error detection after winding, and determining whether to enter the error detection data into the historical database based on the detection results, includes the following steps: Start the winding monitoring equipment; The characteristics of the current transformer are detected by the coil winding process using winding monitoring equipment. The system determines whether the transformer is qualified. If it is qualified, the test data is entered into the historical database. The transformer characteristic test includes error, polarity test and volt-ampere characteristic test. If it is unqualified, the coil winding scheme is corrected.

4. The control method for improving the pass rate of partial discharge test of metering transformers according to claim 1, characterized in that, The coil drying process includes the following steps: Start the coil drying monitoring equipment; The moisture content, vacuum level, and temperature of the coil semi-finished product are collected in real time using coil drying monitoring equipment; The collected moisture content, vacuum degree and temperature are dynamically corrected, and the correction results determine whether to enter the corrected data into the historical database. During the dynamic correction process, the moisture prediction deviation of the control coil semi-finished product is <5%.

5. The control method for improving the pass rate of partial discharge test of metering transformers according to claim 1, characterized in that, The body assembly process includes the following steps: Starter body mold monitoring equipment; The outline and position of the wound coil semi-finished product are analyzed using the body mold monitoring equipment; Construct a three-dimensional insulation distance model of the coil body and perform threshold identification: if the maximum distance in the three-dimensional insulation distance model of the coil body is less than or equal to a set threshold, dynamically correct the position of the coil semi-finished product, and determine whether to enter the analysis data into the historical database based on the correction result.

6. A control system for improving the pass rate of partial discharge tests on metering transformers, characterized in that, The system includes a current transformer core monitoring module, a coil winding monitoring module, a coil drying monitoring module, a transformer body molding module, a mold preheating module, a vacuum casting module, a primary curing module, a mold demolding module, a secondary curing module, and a factory testing module. Each module operates according to the following steps: Current transformer core monitoring module: used to monitor the insulation performance and electromagnetic performance of the core, and to determine whether to enter the current transformer core test data into the historical database based on the test results; If the transformer core detection data is entered into the historical database, the coil winding monitoring module is activated. The winding error is detected through the coil winding monitoring module, and the error detection data is entered into the historical database based on the detection results. If the error detection data is entered into the historical database, the coil drying monitoring module is activated. The coil drying monitoring module dynamically corrects the collected moisture content, vacuum degree and temperature of the coil semi-finished product. Based on the correction results, it is determined whether to enter the correction data into the historical database. If the corrected data is entered into the historical database, the body molding module is activated. The body molding module performs contour and position analysis on the coil semi-finished product after winding, and dynamically corrects the position of the coil semi-finished product. Based on the corrected results, it is determined whether to enter the analysis data into the historical database. If the analysis data is entered into the historical database, the mold preheating module is activated. The mold temperature is collected and dynamically corrected through the mold preheating module. Based on the corrected result, it is determined whether to enter the temperature data into the historical database. If the temperature data is entered into the historical database, the vacuum casting module is activated. The vacuum casting module collects vacuum pressure and vacuum temperature and performs dynamic correction. Based on the correction results, it is determined whether to enter the data corresponding to vacuum pressure and vacuum temperature into the historical database. If the data corresponding to vacuum pressure and vacuum temperature are entered into the historical database, the primary curing module is activated. The temperature of the mold is collected and dynamically corrected through the primary curing module. Based on the corrected result, it is determined whether to enter the temperature of the mold into the historical database. If the temperature of the mold is entered into the historical database, the mold demolding module is activated. The mold demolding module extracts and analyzes the contour of the mold surface, and determines whether to enter the contour analysis data into the historical database based on the extraction and analysis results. If the contour analysis data is entered into the historical database, the secondary curing module is activated. The temperature of the mold surface is collected and dynamically corrected through the secondary curing module. Based on the corrected result, it is determined whether to enter the temperature data of the mold surface into the historical database. If the temperature of the mold surface is entered into the historical database, the factory test module is activated. The finished metering transformer is tested through the factory test module, and the qualified test data is entered into the historical database.

7. The control system for improving the pass rate of partial discharge test of metering transformers according to claim 6, characterized in that, The current transformer core monitoring module is used for: Start the iron core monitoring equipment; The insulation and electromagnetic properties of the iron core are monitored using iron core monitoring equipment. Determine whether the test results are qualified. If qualified, the test data of the transformer core is entered into the historical database. Each core corresponds to a unique ID. The insulation performance monitoring includes interlayer insulation resistance, power frequency withstand voltage and partial discharge. The electromagnetic performance monitoring includes excitation characteristics, remanence coefficient and magnetic flux density.

8. The control system for improving the pass rate of partial discharge test of metering transformers according to claim 6, characterized in that, The coil winding module is used for: Start the winding monitoring equipment; The characteristics of the current transformer are detected by the coil winding process using winding monitoring equipment. The system determines whether the transformer is qualified. If it is qualified, the test data is entered into the historical database. The transformer characteristic test includes error, polarity test and volt-ampere characteristic test. If it is unqualified, the coil winding scheme is corrected in time.

9. The control system for improving the pass rate of partial discharge test of metering transformers according to claim 6, characterized in that, The coil drying module is used for: Start the coil drying monitoring equipment; The moisture content, vacuum level, and temperature of the coil semi-finished product are collected in real time using coil drying monitoring equipment; The collected moisture content, vacuum degree and temperature are dynamically corrected. The correction results are compared with the standard process database to determine whether to enter the corrected data into the historical database. During the dynamic correction process, the moisture prediction deviation of the control coil semi-finished product is <5%.

10. The control system for improving the pass rate of partial discharge test of metering transformers according to claim 6, characterized in that, The body molding module is used for: Starter body mold monitoring equipment; The outline and position of the wound coil semi-finished product are analyzed using the body mold monitoring equipment; Construct a three-dimensional insulation distance model of the coil body and perform threshold identification: If the maximum distance in the three-dimensional insulation distance model of the coil body is less than or equal to the set threshold, the position of the coil semi-finished product is dynamically corrected, and the result of the correction is compared with the standard process database to determine whether to enter the analysis data into the historical database.

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