Insulation performance intelligent test system of transformer

Abstract

The invention discloses an insulating property intelligent test system for a transformer, which comprises a data collection module and a data processing module, and has the beneficial effects that the data collection module is arranged, so that an insulation resistance value, a dielectric constant and a partial discharge signal required for testing the insulating property of the transformer are collected and processed; the insulation performance of the transformer is tested from all aspects, the voltage withstand test module and the leakage current test module are arranged, so that the test result of the transformer is further improved by combining a voltage withstand test and a leakage current test, and the accuracy of the insulation performance of the tested transformer is guaranteed; by arranging the insulating material testing module, the insulating performance of the insulating material used by each component of the transformer is tested, the problem of insulating faults of each component due to the insulating performance of the insulating material is prevented, the insulating condition of the transformer is comprehensively evaluated, and an important basis is provided for maintenance of equipment.

Description

Technical Field

[0001] The invention relates to the technical field of insulation performance testing, and in particular to an intelligent testing system for insulation performance of a transformer. Background Art

[0002] A transformer is a device that uses the principle of electromagnetic induction to change AC voltage. It is mainly composed of a primary coil, a secondary coil, and an iron core (magnetic core). Its main functions are to achieve voltage conversion, current conversion, impedance conversion, and isolation circuits. Transformers can be divided into power transformers and special transformers (such as instrument transformers, test transformers, rectifier transformers, etc.) according to their uses. They can be divided into single-phase transformers and three-phase transformers according to the number of phases. According to the winding form, they can be divided into double-winding transformers, three-winding transformers, and autotransformers. According to the iron core form, they can be divided into core transformers and shell transformers. In the power system, transformers are basic equipment for power transmission and distribution, and are widely used in industries, agriculture, transportation, urban communities, and other fields. In electrical equipment and wireless circuits, transformers are often used for voltage increase and decrease, impedance matching, and safety isolation. In a generator, whether the coil moves through a magnetic field or the magnetic field moves through a fixed coil, an electric potential can be induced in the coil. In both cases, the value of the magnetic flux remains unchanged, but the amount of magnetic flux interlinked with the coil changes. This is the principle of mutual induction. A transformer is an electrical device that uses mutual induction to achieve voltage, current and impedance transformation. The insulation performance test of the transformer plays an extremely important role in the safe and stable operation of the power system. The insulation test can detect whether the insulation system of the transformer is defective or aging, which is an effective means to prevent dangerous situations such as leakage and breakdown. Through insulation testing, potential insulation problems can be discovered and dealt with in a timely manner, thereby ensuring that no safety accidents will occur during the normal operation of the transformer and ensuring the overall safety of the power system. However, the existing insulation performance test of the transformer cannot be combined with multiple aspects for testing, and it is easy for a transformer component to have poor insulation performance, resulting in damage to the entire transformer. In addition, the insulation performance test of the transformer is not diverse enough, and it is not possible to test the insulation performance from multiple aspects, which affects the accuracy of the test and the test evaluation results. Summary of the invention

[0003] The purpose of the present invention is to provide an intelligent testing system for the insulation performance of a transformer, so as to solve the problem that the existing insulation performance test of the transformer mentioned in the above background technology cannot be tested in combination with multiple aspects, and it is easy for a transformer component to have poor insulation performance, resulting in damage to the entire transformer. In addition, the insulation performance test of the transformer is not diverse enough, and it is not possible to test the insulation performance from multiple aspects, which affects the accuracy of the test and the test evaluation results.

[0004] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an intelligent test system for the insulation performance of a transformer, comprising a data collection module, a data processing module, a feature data storage library, a feature data extraction module, an insulation material test module, a fault terminal database, a fault data classification module, a test data analysis module, an insulation performance classification module, a transformer insulation performance judgment module, a withstand voltage test module, a data management module, a leakage current test module and a performance test summary module, wherein the output end of the data collection module is communicatively connected to the input end of the data processing module, the output end of the data processing module is communicatively connected to the input end of the feature data extraction module, the feature data storage library is bidirectionally connected to the feature data extraction module, the output end of the feature data extraction module is communicatively connected to the input end of the insulation material test module, and the output end of the insulation material test module is communicatively connected to the input end of the insulation material test module. The input end of the fault terminal database is communicatively connected, the output end of the fault terminal database is communicatively connected to the input end of the fault data classification module, the output end of the fault data classification module is communicatively connected to the input end of the test data analysis module, the output end of the test data analysis module is communicatively connected to the input end of the insulation performance grading module, the insulation performance grading module is bidirectionally connected to the transformer insulation performance judgment module, the transformer insulation performance judgment module is bidirectionally connected to the performance test summary module, the output end of the fault terminal database is communicatively connected to the input end of the voltage withstand test module, the fault terminal database is bidirectionally connected to the data management module, the output end of the fault terminal database is communicatively connected to the input end of the leakage current test module, and the output ends of the leakage current test module and the voltage withstand test module are both communicatively connected to the input end of the performance test summary module:

[0005] The data collection module is used to collect data related to the insulation performance of the transformer to be tested;

[0006] The data processing module is used to improve the accuracy of the collected data;

[0007] The characteristic data storage library is used to store characteristic data that determines the insulation performance of the transformer in the collected data;

[0008] The feature data extraction module is used to extract the feature data existing in the current test data and perform extraction processing on the data group containing the feature data;

[0009] The insulating material testing module is used to test the insulating properties of the insulating material;

[0010] The fault terminal database is used to obtain each component where the transformer insulation performance failure occurs;

[0011] The fault data classification module is used to classify the corresponding data generated when insulation performance failure occurs in each component;

[0012] The test data analysis module is used to perform insulation state judgment and prediction processing on insulation test data;

[0013] The insulation performance grading module is used to classify the insulation performance values ​​of various components of the transformer with insulation performance failure into primary, secondary, tertiary and tertiary levels;

[0014] The transformer insulation performance judgment module is used to select the insulation performance required by the transformer performance at level one, level two, level three and level four according to the transformer power, operating environment temperature, operating environment humidity, environmental corrosion and electromagnetic interference;

[0015] The withstand voltage test module is used to test the transformer main insulation by applying AC withstand voltage externally;

[0016] The data management module is responsible for storing, managing and querying the test data;

[0017] The leakage current test module is used to measure the leakage current between the transformer winding and the ground or between the windings under a higher test voltage;

[0018] The performance test summary module is used to select components with insulation performance according to level one, level two, level three and level four, and then improve the insulation performance level according to the withstand voltage test module and the leakage current test module to ensure the insulation performance of the transformer.

[0019] Preferably, the data collection module comprises a data collection and classification unit and a data collection unit, and the output end of the data collection and classification unit is communicatively connected with the input end of the data collection unit:

[0020] The data acquisition and classification unit is used to collect various data related to insulation performance from the transformer to be tested;

[0021] The data acquisition unit is used to collect and store insulation resistance values, dielectric constants, and partial discharge signals according to the data collected by the data acquisition classification module.

[0022] Preferably, the data processing module comprises a data filtering unit, a data denoising unit and a data amplifying unit, wherein the data filtering unit is bidirectionally connected to the data denoising unit, and the data denoising unit is bidirectionally connected to the data amplifying unit;

[0023] The data filtering unit is used to remove unnecessary components in the data through mean filtering, median filtering, low-pass filtering and Kalman filtering, and retain useful data information;

[0024] The data denoising unit is used to clean the data and remove the noise components in the data;

[0025] The data amplification unit is used to enhance the expressiveness of data by constructing new features or transforming existing features.

[0026] Preferably, the insulating material testing module comprises an insulation testing unit and a performance evaluation unit, and an output end of the insulation testing unit is communicatively connected to an input end of the performance evaluation unit;

[0027] The insulation testing unit is used to test the absorption ratio and polarization index of the insulation material used in the transformer;

[0028] The performance evaluation unit is used to evaluate the performance of the insulation material, and the insulation performance of the transformer is tested and evaluated through the insulation material.

[0029] Preferably, the fault terminal database includes a main insulation and turn-to-turn insulation data acquisition unit, an insulating oil data acquisition unit, a lead insulation data acquisition unit, a core insulation data acquisition unit, a bushing flashover and explosion data acquisition unit, and a tap changer fault data acquisition unit:

[0030] The main insulation and inter-turn insulation data acquisition unit is used to monitor the status of the main insulation system of the transformer power equipment and monitor the inter-turn insulation of the transformer winding;

[0031] The insulating oil data acquisition unit is used to monitor the insulating oil status of oil-immersed power equipment such as transformers;

[0032] The lead insulation data acquisition unit is used to monitor the insulation status of the transformer inlet and outlet leads;

[0033] The core insulation data acquisition unit is used to monitor the core insulation of transformers and other equipment;

[0034] The bushing flashover and explosion data acquisition unit is used to monitor the bushing status of equipment such as transformers;

[0035] The tap changer fault data acquisition unit is used to monitor the operating status of the on-load tap changer equipment.

[0036] Preferably, the test data analysis module comprises a test model building unit and an insulation state judgment prediction unit, and the output end of the test model building unit is communicatively connected to the input end of the insulation state judgment prediction unit;

[0037] The test model establishment unit is used to establish a test algorithm and a test model for transformer insulation performance test data;

[0038] The insulation state judgment prediction unit is used to perform intelligent analysis on the test data through a test algorithm and a test model to evaluate the insulation performance of the transformer.

[0039] Preferably, the test model building unit specifically includes fault diagnosis based on machine learning and knowledge reasoning methods based on expert systems to accurately judge and predict the insulation state of the transformer.

[0040] Preferably, the withstand voltage test module comprises an AC voltage applying unit, a voltage stabilizing unit and a defect detection unit, wherein the output end of the AC voltage applying unit is communicatively connected to the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is communicatively connected to the input end of the defect detection unit;

[0041] The AC voltage applying unit is used to ground the transformer core and the shell, connect the winding terminal to the live wire, and ground the terminal of the non-tested winding, and observe the insulation tolerance of the transformer by applying AC voltage;

[0042] The voltage stabilizing unit is used to maintain the test voltage stable for a certain period of time after reaching the standard, and to cut off the power supply after rapidly dropping to the safe voltage;

[0043] The defect detection unit is used to detect defects such as contamination, moisture and looseness of the winding.

[0044] Preferably, the data management module comprises a test data storage unit, a data query unit and a data sharing unit, the test data storage unit is bidirectionally connected to the data query unit, and the data query unit is bidirectionally connected to the data sharing unit;

[0045] The test data storage unit is used to store data and save a large amount of test data;

[0046] The data query unit is used to provide query and retrieval functions for the test data storage unit;

[0047] The data sharing unit is used to remotely transmit and share data, and realize data sharing and collaboration between different locations and departments.

[0048] Preferably, the leakage current test module comprises a voltage applying unit and an insulation position analysis unit, and the output end of the voltage applying unit is communicatively connected to the input end of the insulation position analysis unit;

[0049] The voltage applying unit is used to read the current value through a microammeter and monitor the voltage application time and stability;

[0050] The insulation part analysis unit is used to expose the concentrated defects that have not been penetrated by measuring the leakage current, and analyze the insulation problem parts.

[0051] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure.

[0052] Compared with the prior art, the beneficial effects of the present invention are as follows: by setting up a data collection module, the insulation resistance value, dielectric constant and partial discharge signal required for testing the insulation of the transformer can be collected and processed, and the insulation performance of the transformer can be tested and processed from various aspects; by setting up a withstand voltage test module and a leakage current test module, the transformer test result can be further improved by combining the withstand voltage test and the leakage current test, and the accuracy of the insulation performance of the test transformer can be guaranteed; by setting up an insulation material test module, the insulation performance of the insulation materials used in various components of the transformer can be tested, and the problem of insulation failure of various components due to the insulation performance of the insulation materials can be prevented, and a comprehensive evaluation of the insulation condition of the transformer can be performed, providing an important basis for the maintenance and servicing of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the drawings required for the implementation methods or the prior art descriptions are briefly introduced below. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0054] Figure 1 This is a system block diagram of the present invention. DETAILED DESCRIPTION

[0055] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices consistent with some aspects of the present disclosure as detailed in the appended claims.

[0056] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] See also Figure 1As shown, an intelligent test system for insulation performance of a transformer according to an embodiment of the present invention comprises a data collection module, a data processing module, a feature data storage library, a feature data extraction module, an insulation material test module, a fault terminal database, a fault data classification module, a test data analysis module, an insulation performance classification module, a transformer insulation performance judgment module, a withstand voltage test module, a data management module, a leakage current test module and a performance test summary module, wherein the output end of the data collection module is communicatively connected to the input end of the data processing module, the output end of the data processing module is communicatively connected to the input end of the feature data extraction module, the feature data storage library is bidirectionally connected to the feature data extraction module, the output end of the feature data extraction module is communicatively connected to the input end of the insulation material test module, the output end of the insulation material test module is communicatively connected to the fault terminal database ... The input end of the fault terminal database is communicated and connected, the output end of the fault terminal database is communicated and connected with the input end of the fault data classification module, the output end of the fault data classification module is communicated and connected with the input end of the test data analysis module, the output end of the test data analysis module is communicated and connected with the input end of the insulation performance grading module, the insulation performance grading module is bidirectionally connected with the transformer insulation performance judgment module, the transformer insulation performance judgment module is bidirectionally connected with the performance test summary module, the output end of the fault terminal database is communicated and connected with the input end of the voltage test module, the fault terminal database is bidirectionally connected with the data management module, the output end of the fault terminal database is communicated and connected with the input end of the leakage current test module, and the output ends of the leakage current test module and the voltage test module are both communicated and connected with the input end of the performance test summary module:

[0058] The data collection module is used to collect data related to the insulation performance of the transformer to be tested;

[0059] The data processing module is used to improve the accuracy of the collected data;

[0060] The characteristic data storage library is used to store characteristic data that determines the insulation performance of the transformer in the collected data;

[0061] The feature data extraction module is used to extract the feature data existing in the current test data and perform extraction processing on the data group with the feature data;

[0062] The insulation material test module is used to test the insulation performance of insulation materials;

[0063] The fault terminal database is used to obtain each component with transformer insulation performance failure;

[0064] The fault data classification module is used to classify the corresponding data that occurs when insulation performance failure occurs in each component;

[0065] The test data analysis module is used to judge and predict the insulation status of insulation test data;

[0066] The insulation performance classification module is used to classify the insulation performance values ​​of various components of the transformer with insulation performance failure into primary, secondary, tertiary and tertiary levels;

[0067] The transformer insulation performance judgment module is used to select the primary, secondary, tertiary and quaternary insulation performance required for the transformer performance according to the transformer power, operating environment temperature, operating environment humidity, environmental corrosion and electromagnetic interference;

[0068] The withstand voltage test module is used to inspect the transformer main insulation by applying AC withstand voltage externally;

[0069] The data management module is responsible for storing, managing and querying test data;

[0070] The leakage current test module is used to measure the leakage current between transformer winding and ground or between windings under higher test voltage;

[0071] The performance test summary module is used to select components with insulation performance according to level one, level two, level three and level four, and then use the withstand voltage test module and the leakage current test module to improve the insulation performance level to ensure the insulation performance of the transformer.

[0072] The data collection module includes a data collection and classification unit and a data collection unit, and the output end of the data collection and classification unit is communicatively connected with the input end of the data collection unit:

[0073] The data acquisition and classification unit is used to collect various data related to insulation performance from the transformer to be tested;

[0074] The data acquisition unit is used to collect and store insulation resistance values, dielectric constants, and partial discharge signals according to the data collected by the data acquisition classification module.

[0075] The data processing module includes a data filtering unit, a data denoising unit and a data amplifying unit, the data filtering unit is bidirectionally connected to the data denoising unit, and the data denoising unit is bidirectionally connected to the data amplifying unit;

[0076] The data filtering unit is used to remove unnecessary components in the data through mean filtering, median filtering, low-pass filtering and Kalman filtering, and retain useful data information;

[0077] The data denoising unit is used to clean the data and remove the noise components in the data;

[0078] The data amplification unit is used to enhance the expressiveness of data by constructing new features or transforming existing features.

[0079] Wherein, the insulation material testing module includes an insulation testing unit and a performance evaluation unit, and the output end of the insulation testing unit is communicatively connected with the input end of the performance evaluation unit;

[0080] The insulation test unit is used to test the absorption ratio and polarization index of the insulation material used in the transformer;

[0081] The performance evaluation unit is used to evaluate the performance of insulating materials. The insulation performance of the transformer is tested and evaluated through the insulating materials. The absorption ratio refers to the ratio of the insulation resistance value when pressurized for 60 seconds to the insulation resistance value when pressurized for 15 seconds at the same temperature (R60s / R15s). The polarization index refers to the ratio of the insulation resistance value when pressurized for 10 minutes to the insulation resistance value when pressurized for 1 minute at the same temperature (R10min / R1min). The performance of the insulating materials, especially the insulation state of materials such as insulating paper or insulating cardboard, is further evaluated. For transformers of 35kV and above and a capacity of 4000kVA and above, the absorption ratio should be measured; for transformers of 220kV and above and a capacity of 120MVA and above, the polarization index should be measured. There should be no significant difference between the absorption ratio and polarization index compared with the factory value of the product, and it is generally not less than 1.3 at room temperature. When the insulation resistance value is very large (such as R60s greater than 3000MΩ or 10000MΩmin), the assessment requirements of the absorption ratio or polarization index can be appropriately relaxed.

[0082] Among them, the fault terminal database includes main insulation and turn-to-turn insulation data acquisition unit, insulation oil data acquisition unit, lead insulation data acquisition unit, core insulation data acquisition unit, bushing flashover and explosion data acquisition unit and tap changer fault data acquisition unit:

[0083] The main insulation and inter-turn insulation data acquisition unit is used to monitor the status of the main insulation system of the transformer power equipment and monitor the inter-turn insulation of the transformer winding;

[0084] The insulating oil data acquisition unit is used to monitor the insulating oil status of oil-immersed power equipment such as transformers;

[0085] The lead insulation data acquisition unit is used to monitor the insulation status of the transformer inlet and outlet leads;

[0086] The core insulation data acquisition unit is used to monitor the core insulation of transformers and other equipment;

[0087] The bushing flashover and explosion data acquisition unit is used to monitor the bushing status of equipment such as transformers;

[0088] The tap changer fault data acquisition unit is used to monitor the operating status of the on-load tap changer equipment.

[0089] The test data analysis module includes a test model building unit and an insulation state judgment prediction unit, and the output end of the test model building unit is communicatively connected to the input end of the insulation state judgment prediction unit;

[0090] The test model building unit is used to build the test algorithm and test model for the transformer insulation performance test data;

[0091] The insulation status judgment prediction unit is used to perform intelligent analysis on the test data through the test algorithm and test model to evaluate the insulation performance of the transformer.

[0092] Among them, the test model establishment unit specifically includes fault diagnosis based on machine learning and knowledge reasoning methods based on expert systems to accurately judge and predict the insulation status of the transformer.

[0093] The withstand voltage test module includes an AC voltage applying unit, a voltage stabilizing unit and a defect detection unit, wherein the output end of the AC voltage applying unit is communicatively connected to the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is communicatively connected to the input end of the defect detection unit;

[0094] The AC voltage application unit is used to ground the transformer core and shell, connect the live wire to the winding terminal, and ground the terminal of the non-test winding. By applying AC voltage, the insulation tolerance of the transformer can be observed.

[0095] The voltage stabilizing unit is used to maintain the test voltage stable for a certain period of time after it reaches the standard, and cut off the power supply after it drops to the safe voltage quickly;

[0096] The defect detection unit is used to detect defects such as contamination, moisture and looseness of the winding;

[0097] By applying a test voltage higher than the rated voltage of the transformer, it is detected whether the transformer insulation system can withstand the voltage without breakdown or damage. The withstand voltage test can reveal potential defects in the insulation system, such as cracks, bubbles, moisture, etc., so as to evaluate whether the insulation performance meets the requirements, timely discover and deal with insulation problems, prevent accidents caused by insulation breakdown, and ensure the safe and stable operation of the power system.

[0098] The data management module includes a test data storage unit, a data query unit and a data sharing unit. The test data storage unit is bidirectionally connected to the data query unit, and the data query unit is bidirectionally connected to the data sharing unit.

[0099] The test data storage unit is used to store data and save a large amount of test data;

[0100] The data query unit is used to provide query and retrieval functions for the test data storage unit;

[0101] The data sharing unit is used to remotely transmit and share data, and realize data sharing and collaboration between different locations and departments.

[0102] Wherein, the leakage current test module includes a voltage applying unit and an insulation part analysis unit, and the output end of the voltage applying unit is communicatively connected with the input end of the insulation part analysis unit;

[0103] The voltage application unit is used to read the current value through a microammeter and monitor the voltage application time and stability;

[0104] The insulation part analysis unit is used to expose the concentrated defects that have not yet penetrated by measuring the leakage current, and analyze the insulation problem parts. The test is sensitive to the defects of windings and bushings, and the measurement results are more accurate than measuring insulation resistance. During the test, a high DC voltage is applied to observe the leakage current of the insulation system. It can sensitively reflect the cracks in the insulating material, the internal moisture and local loose fractures of the interlayer insulation, the deterioration of the insulating oil, and the surface carbonization defects of the insulation. The test voltage is generally higher than the megohmmeter voltage and can be adjusted arbitrarily. AC withstand voltage method: 50Hz AC voltage is applied during the test to observe the leakage current of the insulation system and check the main insulation problems of the transformer, such as contaminated, damp, loose windings, insufficient lead distance and cracks in the windings.

[0105] Specifically, various data related to insulation performance are collected from the transformer to be tested. The collected data include insulation resistance value, dielectric constant, and partial discharge signal, and the mean filter takes the average value of the N surrounding points for each point in the data set as the filtering result of the point. This method is simple but may blur the signal; weighted mean filtering (such as Gaussian filtering) is an improvement of mean filtering, in which the weights of the surrounding points vary according to their distance from the center point, which can better preserve the details of the signal; median filtering is a nonlinear filtering technology that replaces each point in the data set with the median of the N surrounding points; low-pass filtering is mainly used to remove high-frequency noise and retain low-frequency signals. In digital signal processing, this can be achieved by performing a Fourier transform on the signal, then removing the high-frequency components, and finally performing an inverse Fourier transform. Data denoising is a specific application of filtering, and its main purpose is to remove the noise component in the data. Data amplification processing usually does not refer to a simple amplification of the original data value (such as multiplying by a constant), because this may cause the data to be distorted or exceed a reasonable range. However, in some cases, it may be necessary to "amplify" a certain aspect or feature of the data for better analysis or visualization. By adjusting the scale of the data (such as scaling the range of the data to between 0 and 1) or changing its distribution (such as making the data have zero mean and unit variance), certain features in the data can be made more prominent in subsequent analysis. In machine learning, the expressiveness of the data can be enhanced by constructing new features or transforming existing features. For example, in image processing, filters can be used to enhance the edge information of the image. In some cases, different parts of the data can be given different weights to "amplify" their importance.This can be achieved in a variety of machine learning algorithms such as regression analysis and cluster analysis to evaluate the performance of insulating materials. The insulation performance of the transformer is tested and evaluated through insulating materials. The absorption ratio refers to the ratio of the insulation resistance value when pressurized for 60 seconds to the insulation resistance value when pressurized for 15 seconds at the same temperature (R60s / R15s). The polarization index refers to the ratio of the insulation resistance value when pressurized for 10 minutes to the insulation resistance value when pressurized for 1 minute at the same temperature (R10min / R1min). The performance of the insulating material is further evaluated, especially the insulation state of materials such as insulating paper or insulating cardboard. For 35kV and above with a capacity of 40 For transformers with a capacity of 220kV and above and a capacity of 120MVA and above, the absorption ratio should be measured; for transformers with a capacity of 220kV and above and a capacity of 120MVA and above, the polarization index should be measured. There should be no significant difference between the absorption ratio and polarization index compared with the factory value of the product, and it should generally not be less than 1.3 at room temperature. When the insulation resistance value is very large (such as R60s greater than 3000MΩ or 10000MΩ minutes), the assessment requirements for the absorption ratio or polarization index can be appropriately relaxed. The corresponding data that appears when the insulation performance failure of each component occurs is classified and processed, and the test algorithm and test model for the transformer insulation performance test data are established. The test data is tested through the test algorithm and test model. Intelligent analysis is used to evaluate the insulation performance of the transformer. By applying a test voltage higher than the rated voltage of the transformer, it is detected whether the transformer insulation system can withstand the voltage without breakdown or damage. The withstand voltage test can reveal potential defects in the insulation system, such as cracks, bubbles, moisture, etc., so as to evaluate whether the insulation performance meets the requirements, timely discover and deal with insulation problems, prevent accidents caused by insulation breakdown, and ensure the safe and stable operation of the power system. During the test, a high DC voltage is applied to observe the leakage current of the insulation system, which sensitively reflects the cracks in the insulation material, the internal moisture and local loose fracture of the sandwich insulation, the deterioration of the insulating oil, and the surface carbonization defects of the insulation. The test voltage is generally higher than the megohmmeter voltage and can be adjusted arbitrarily. AC withstand voltage method: apply 50Hz AC voltage during the test, observe the leakage current of the insulation system, and check the main insulation problems of the transformer, such as contamination, moisture, looseness of the winding, insufficient lead distance and cracks in the winding. According to the power of the transformer, the operating environment temperature, the operating environment humidity, environmental corrosion and electromagnetic interference, the insulation performance required for the transformer performance is selected in the first, second, third and fourth levels. After the components with insulation performance are selected according to the first, second, third and fourth levels, the insulation performance level is improved according to the withstand voltage test module and the leakage current test module to ensure the insulation performance of the transformer.

[0106] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

[0107] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are intended to be exemplary only, and the true scope of the present disclosure is indicated by the following claims.

Claims

1. An intelligent testing system for transformer insulation performance, characterized in that: It includes a data collection module, a data processing module, a feature data storage library, a feature data extraction module, an insulation material test module, a fault terminal database, a fault data classification module, a test data analysis module, an insulation performance classification module, a transformer insulation performance judgment module, a voltage resistance test module, a data management module, a leakage current test module and a performance test summary module, wherein the output end of the data collection module is communicatively connected to the input end of the data processing module, the output end of the data processing module is communicatively connected to the input end of the feature data extraction module, the feature data storage library is bidirectionally connected to the feature data extraction module, the output end of the feature data extraction module is communicatively connected to the input end of the insulation material test module, the output end of the insulation material test module is communicatively connected to the input end of the fault terminal database, and the The output end of the fault terminal database is communicatively connected to the input end of the fault data classification module, the output end of the fault data classification module is communicatively connected to the input end of the test data analysis module, the output end of the test data analysis module is communicatively connected to the input end of the insulation performance grading module, the insulation performance grading module is bidirectionally connected to the transformer insulation performance judgment module, the transformer insulation performance judgment module is bidirectionally connected to the performance test summary module, the output end of the fault terminal database is communicatively connected to the input end of the voltage withstand test module, the fault terminal database is bidirectionally connected to the data management module, the output end of the fault terminal database is communicatively connected to the input end of the leakage current test module, and the output ends of the leakage current test module and the voltage withstand test module are both communicatively connected to the input end of the performance test summary module: The data collection module is used to collect data related to the insulation performance of the transformer to be tested; The data processing module is used to improve the accuracy of the collected data; The characteristic data storage library is used to store characteristic data that determines the insulation performance of the transformer in the collected data; The feature data extraction module is used to extract the feature data existing in the current test data and perform extraction processing on the data group containing the feature data; The insulating material testing module is used to test the insulating properties of the insulating material; The fault terminal database is used to obtain each component where the transformer insulation performance failure occurs; The fault data classification module is used to classify the corresponding data generated when insulation performance failure occurs in each component; The test data analysis module is used to perform insulation state judgment and prediction processing on insulation test data; The insulation performance grading module is used to classify the insulation performance values ​​of various components of the transformer with insulation performance failure into primary, secondary, tertiary and tertiary levels; The transformer insulation performance judgment module is used to select the insulation performance required by the transformer performance at level one, level two, level three and level four according to the transformer power, operating environment temperature, operating environment humidity, environmental corrosion and electromagnetic interference; The withstand voltage test module is used to test the transformer main insulation by applying AC withstand voltage externally; The data management module is responsible for storing, managing and querying the test data; The leakage current test module is used to measure the leakage current between the transformer winding and the ground or between the windings under a higher test voltage; The performance test summary module is used to select components with insulation performance according to level one, level two, level three and level four, and then improve the insulation performance level according to the withstand voltage test module and the leakage current test module to ensure the insulation performance of the transformer.

2. The intelligent testing system for transformer insulation performance according to claim 1, characterized in that: The data collection module includes a data collection and classification unit and a data collection unit, wherein the output end of the data collection and classification unit is communicatively connected to the input end of the data collection unit: The data acquisition and classification unit is used to collect various data related to insulation performance from the transformer to be tested; The data acquisition unit is used to collect and store insulation resistance values, dielectric constants, and partial discharge signals according to the data collected by the data acquisition classification module.

3. The intelligent testing system for transformer insulation performance according to claim 2 is characterized in that: The data processing module includes a data filtering unit, a data denoising unit and a data amplifying unit, wherein the data filtering unit is bidirectionally connected to the data denoising unit, and the data denoising unit is bidirectionally connected to the data amplifying unit; The data filtering unit is used to remove unnecessary components in the data through mean filtering, median filtering, low-pass filtering and Kalman filtering, and retain useful data information; The data denoising unit is used to clean the data and remove the noise components in the data; The data amplification unit is used to enhance the expressiveness of data by constructing new features or transforming existing features.

4. The intelligent testing system for transformer insulation performance according to claim 3 is characterized in that: The insulating material testing module comprises an insulating testing unit and a performance evaluation unit, wherein an output end of the insulating testing unit is communicatively connected to an input end of the performance evaluation unit; The insulation testing unit is used to test the absorption ratio and polarization index of the insulation material used in the transformer; The performance evaluation unit is used to evaluate the performance of the insulation material, and the insulation performance of the transformer is tested and evaluated through the insulation material.

5. The intelligent testing system for transformer insulation performance according to claim 4, characterized in that: The fault terminal database includes a main insulation and turn-to-turn insulation data acquisition unit, an insulating oil data acquisition unit, a lead insulation data acquisition unit, a core insulation data acquisition unit, a bushing flashover and explosion data acquisition unit, and a tap changer fault data acquisition unit: The main insulation and inter-turn insulation data acquisition unit is used to monitor the status of the main insulation system of the transformer power equipment and monitor the inter-turn insulation of the transformer winding; The insulating oil data acquisition unit is used to monitor the insulating oil status of oil-immersed power equipment such as transformers; The lead insulation data acquisition unit is used to monitor the insulation status of the transformer inlet and outlet leads; The core insulation data acquisition unit is used to monitor the core insulation of transformers and other equipment; The bushing flashover and explosion data acquisition unit is used to monitor the bushing status of equipment such as transformers; The tap changer fault data acquisition unit is used to monitor the operating status of the on-load tap changer equipment.

6. The intelligent testing system for transformer insulation performance according to claim 5, characterized in that: The test data analysis module includes a test model building unit and an insulation state judgment prediction unit, wherein the output end of the test model building unit is communicatively connected to the input end of the insulation state judgment prediction unit; The test model establishment unit is used to establish a test algorithm and a test model for transformer insulation performance test data; The insulation state judgment prediction unit is used to perform intelligent analysis on the test data through a test algorithm and a test model to evaluate the insulation performance of the transformer.

7. The intelligent testing system for transformer insulation performance according to claim 6, characterized in that: The test model building unit specifically includes fault diagnosis based on machine learning and knowledge reasoning methods based on expert systems to accurately judge and predict the insulation state of the transformer.

8. The intelligent testing system for transformer insulation performance according to claim 7, characterized in that: The withstand voltage test module includes an AC voltage applying unit, a voltage stabilizing unit and a defect detection unit, wherein the output end of the AC voltage applying unit is communicatively connected to the input end of the voltage stabilizing unit, and the output end of the voltage stabilizing unit is communicatively connected to the input end of the defect detection unit; The AC voltage applying unit is used to ground the transformer core and the shell, connect the winding terminal to the live wire, and ground the terminal of the non-tested winding, and observe the insulation tolerance of the transformer by applying AC voltage; The voltage stabilizing unit is used to maintain the test voltage stable for a certain period of time after reaching the standard, and to cut off the power supply after rapidly dropping to the safe voltage; The defect detection unit is used to detect defects such as contamination, moisture and looseness of the winding.

9. The intelligent testing system for transformer insulation performance according to claim 8, characterized in that: The data management module includes a test data storage unit, a data query unit and a data sharing unit, wherein the test data storage unit is bidirectionally connected to the data query unit, and the data query unit is bidirectionally connected to the data sharing unit; The test data storage unit is used to store data and save a large amount of test data; The data query unit is used to provide query and retrieval functions for the test data storage unit; The data sharing unit is used to remotely transmit and share data, and realize data sharing and collaboration between different locations and departments.

10. The intelligent testing system for transformer insulation performance according to claim 9, characterized in that: The leakage current test module comprises a voltage applying unit and an insulation position analysis unit, wherein the output end of the voltage applying unit is communicatively connected to the input end of the insulation position analysis unit; The voltage applying unit is used to read the current value through a microammeter and monitor the voltage application time and stability; The insulation part analysis unit is used to expose the concentrated defects that have not been penetrated by measuring the leakage current, and analyze the insulation problem parts.

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