System and method for detecting damping degree of buffer layer of high-voltage cable

Abstract

The invention provides a damping degree detection system and method for a high-voltage cable buffer layer, and relates to the technical field of high-voltage cable fault diagnosis. The system comprises a gas collection assembly used for collecting gap gas of a buffer layer; the gas chromatograph is communicated with the gas collection assembly and is used for analyzing the hydrogen peak area of the gap gas; a dry absorbent layer is arranged in the metering assembly, and the metering assembly is used for metering the mass increment when the gap gas flows through the dry absorbent layer; the computer system is connected with the gas chromatograph and the metering assembly and is used for determining the volume fraction of hydrogen in the interstitial gas according to the hydrogen peak area of the interstitial gas; determining the mass fraction of water in the interstitial gas according to the mass increment; and determining the damping degree value of the buffer layer according to the hydrogen volume fraction and the moisture mass fraction based on the incidence relation between the damping degree of the buffer layer and the hydrogen volume fraction and the moisture mass fraction. The damping degree detection accuracy of the buffer layer can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of high-voltage cable fault diagnosis, and in particular to a system and method for detecting the moisture content of a buffer layer of a high-voltage cable. Background Art

[0002] From the inside out, a high-voltage cable typically consists of a conductor, a conductor shield, an insulation layer, an insulation shield, a buffer layer, a metal sheath, and an outer sheath. The buffer layer is a crucial component of high-voltage cables, absorbing and compensating for the mechanical stress generated between the metal sheath and the insulation system due to thermal expansion and contraction, protecting the insulation and shielding layers. It also prevents moisture from entering the insulation layer, protecting the cable's internal structure. However, moisture intrusion can trigger a chain reaction within the buffer layer, damaging its mechanical properties, inducing and accelerating partial discharge, eroding the insulation layer, accelerating overall cable aging, and causing ablation of the high-voltage cable, among other serious consequences.

[0003] Specifically, after ambient moisture penetrates the buffer layer through the sealing defects of the high-voltage cable, the water-blocking material in the polyester fiber absorbs water and hydrolyzes, resulting in volume expansion and loose structure, forming local high-resistance areas. The current is forced to concentrate at the corrugations of the aluminum sheath, causing Joule heat accumulation and pyrolysis and carbonization. At the same time, moisture acts as an electrolyte to accelerate the electrochemical corrosion of the aluminum sheath, generating gases such as hydrogen. Corrosion products exacerbate contact degradation, and hydrogen reduces material strength through the hydrogen embrittlement effect, forming a vicious cycle from local discharge to complete breakdown. The moisture content directly determines the corrosion rate and the magnitude of gas generation. For example, when the moisture content exceeds the critical value, the hydrogen concentration will surge nonlinearly and be accompanied by the appearance of ablation characteristic gases. Therefore, it is necessary to accurately detect the moisture content of the buffer layer of the high-voltage cable.

[0004] Related technologies use gas detection technology to capture characteristic gases such as hydrogen in the buffer layer, and determine the moisture detection results of the buffer layer based on the relationship between the concentration of the characteristic gas and the alarm threshold. However, there is a problem of inaccurate moisture detection results. Summary of the Invention

[0005] The embodiments of the present application provide a system and method for detecting the moisture content of a buffer layer of a high-voltage cable, so as to improve the accuracy of detecting the moisture content of the buffer layer of the high-voltage cable.

[0006] In a first aspect, an embodiment of the present application provides a system for detecting moisture levels in a buffer layer of a high-voltage cable, comprising:

[0007] A gas collection component, used for collecting interstitial gas in the buffer layer;

[0008] a gas chromatograph, connected to the gas collection assembly, for analyzing the hydrogen peak area of ​​the interstitial gas;

[0009] a metering assembly having a dry absorbent layer therein for measuring the mass increment of interstitial gas when it flows through the dry absorbent layer;

[0010] The computer system is connected to the gas chromatograph and the metering component, and is used to determine the hydrogen volume fraction in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas; determine the water mass fraction in the interstitial gas based on the mass increment; and determine the moisture level of the buffer layer based on the hydrogen volume fraction and the water mass fraction based on the correlation between the moisture level of the buffer layer and the hydrogen volume fraction and the water mass fraction.

[0011] In one possible implementation, the computer system, based on the correlation between the moisture level of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determines the moisture level of the buffer layer according to the hydrogen gas volume fraction and the water mass fraction, specifically is used to:

[0012] The hydrogen gas integral fraction and the water mass fraction are substituted into the moisture degree assessment model to obtain the moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas integral fraction and the water mass fraction.

[0013] In a possible implementation, the moisture degree assessment model is constructed in the following manner:

[0014] Obtaining high-voltage cable sample data, the high-voltage cable sample data including the hydrogen gas volume fraction, moisture mass fraction, and buffer layer moisture degree of the high-voltage cable sample;

[0015] Based on the sample data of high-voltage cables, a multivariate regression equation was fitted using the least squares method. The multivariate regression equation is used to reflect the combined effect of the hydrogen gas volume fraction and the water mass fraction on the moisture content of the buffer layer of the high-voltage cable.

[0016] Based on the multiple regression equation, random error terms are set to obtain the moisture degree assessment model. The random error terms reflect the random compensation for the output results of the moisture degree assessment model.

[0017] In one possible implementation, when determining the volume fraction of hydrogen gas in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas, the computer system is specifically configured to:

[0018] Determine the ratio of the hydrogen peak area in the standard gas to the hydrogen peak area in the interstitial gas;

[0019] The product of the ratio and the hydrogen gas volume fraction in the standard gas is used as the hydrogen gas volume fraction in the gap gas.

[0020] In one possible implementation, when determining the moisture mass fraction in the interstitial gas based on the mass increment, the computer system is specifically configured to:

[0021] The moisture mass fraction in the interstitial gas is obtained based on the ratio of the mass increment to the total amount of interstitial gas flowing through the dry absorbent layer.

[0022] In one possible embodiment, the gas collection assembly includes:

[0023] A vacuum pump, whose air inlet is connected to the air extraction valve and whose air outlet is connected to the sealed air bag, is used to extract the interstitial gas of the buffer layer into the sealed air bag through the air extraction valve, wherein the air extraction valve is set at the wave crest drilling of the aluminum sheath of the high-voltage cable.

[0024] In a possible embodiment, a suction device is provided on the metering component, and the suction device is used to make the gap gas flow through the dry absorbent layer.

[0025] In a second aspect, embodiments of the present application provide a method for detecting moisture levels in a buffer layer of a high-voltage cable, which is applied to a computer system in a buffer layer moisture level detection system as described in the first aspect and / or various possible embodiments of the first aspect. The method for detecting moisture levels in the buffer layer includes:

[0026] Real-time acquisition of the hydrogen peak area of ​​the interstitial gas in the buffer layer of the high-voltage cable. The hydrogen peak area is obtained by gas chromatography analysis in the buffer layer moisture detection system.

[0027] Real-time acquisition of mass increments collected when gap gas flows through metering components in the buffer layer moisture detection system;

[0028] Determine the hydrogen volume fraction in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas;

[0029] According to the mass increment, the water mass fraction in the interstitial gas is determined;

[0030] Based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, the moisture degree value of the buffer layer is determined according to the hydrogen gas volume fraction and the water mass fraction.

[0031] In one possible implementation, based on the correlation between the moisture level of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determining the moisture level of the buffer layer according to the hydrogen gas volume fraction and the water mass fraction includes:

[0032] The hydrogen gas integral fraction and the water mass fraction are substituted into the moisture degree assessment model to obtain the moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas integral fraction and the water mass fraction.

[0033] In a possible implementation, the moisture degree assessment model is constructed in the following manner:

[0034] Obtaining high-voltage cable sample data, the high-voltage cable sample data including the hydrogen gas volume fraction, moisture mass fraction, and buffer layer moisture degree of the high-voltage cable sample;

[0035] Based on historical operating cable sample data, a multivariate regression equation was fitted using the least squares method. The multivariate regression equation is used to reflect the combined effect of hydrogen gas volume fraction and water mass fraction on the moisture content of the buffer layer of high-voltage cables.

[0036] Based on the multiple regression equation, random error terms are set to obtain the moisture degree assessment model. The random error terms reflect the random compensation for the output results of the moisture degree assessment model.

[0037] In a third aspect, embodiments of the present application provide a device for detecting the moisture content of a buffer layer of a high-voltage cable, which is applied to a computer system in a system for detecting the moisture content of a buffer layer as described in the first aspect and / or various possible embodiments of the first aspect. The device for detecting the moisture content of a buffer layer includes:

[0038] an acquisition module, configured to acquire in real time the hydrogen peak area of ​​the interstitial gas in the buffer layer of the high-voltage cable, the hydrogen peak area being obtained by analysis by a gas chromatograph in the buffer layer moisture degree detection system; and to acquire in real time the mass increment collected when the interstitial gas flows through the metering component in the buffer layer moisture degree detection system;

[0039] A determination module is used to determine the hydrogen gas volume fraction in the gap gas based on the hydrogen peak area of ​​the gap gas; determine the water mass fraction in the gap gas based on the mass increment; based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determine the moisture degree value of the buffer layer according to the hydrogen gas volume fraction and the water mass fraction.

[0040] In a fourth aspect, an embodiment of the present application provides a computer system, including: a memory, a processor;

[0041] Memory stores computer-executable instructions;

[0042] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above second aspect and / or various possible implementations of the second aspect.

[0043] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed, they are used to implement the above second aspect and / or various possible implementation methods of the second aspect.

[0044] In a sixth aspect, an embodiment of the present application provides a computer program product, including a computer program, which implements the above second aspect and / or various possible implementation methods of the second aspect when the computer program is executed.

[0045] The embodiments of the present application provide a system and method for detecting the moisture content of a high-voltage cable buffer layer. A gas collection component is provided to collect the interstitial gas of the buffer layer, a gas chromatograph is used to determine the hydrogen peak area in the interstitial gas, a metering component provided with a desiccant absorption layer is used to measure the moisture content in the interstitial gas, and a computer system is used to determine the hydrogen gas integral fraction and the moisture mass fraction in the interstitial gas. Furthermore, based on the correlation between the moisture content of the buffer layer and the hydrogen gas integral fraction and the moisture mass fraction, the moisture content value of the buffer layer is determined according to the hydrogen gas integral fraction and the moisture mass fraction, thereby breaking through the limitations of traditional monitoring based only on the concentration of characteristic gases and improving the accuracy of detecting the moisture content of the buffer layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0047] Figure 1 A schematic diagram of the structure of a buffer layer moisture degree detection system provided in an embodiment of the present application;

[0048] Figure 2 A schematic diagram of a scenario in which a computer system analyzes hydrogen gas volume fractions according to an embodiment of the present application;

[0049] Figure 3 A schematic diagram of a scenario in which interstitial gas flows through a dry absorbent layer according to an embodiment of the present application;

[0050] Figure 4 A schematic flow chart of a method for detecting moisture levels in a buffer layer of a high-voltage cable provided in an embodiment of the present application;

[0051] Figure 5 A schematic diagram of the process of constructing a model for evaluating the degree of moisture in a buffer layer according to an embodiment of the present application;

[0052] Figure 6 A schematic diagram of residual distribution of the moisture degree assessment model provided in an embodiment of the present application;

[0053] Figure 7 A schematic structural diagram of a device for detecting moisture levels in a buffer layer of a high-voltage cable provided in an embodiment of the present application;

[0054] Figure 8 This is a schematic diagram of the structure of the device for detecting the moisture content of the buffer layer of a high-voltage cable provided in this application.

[0055] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0056] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0057] Related technologies rely solely on hydrogen concentration detection to infer the degree of moisture in the buffer layer. Their core flaw stems from a single-parameter detection system. For example, they only detect characteristic gases such as hydrogen, resulting in insufficient analysis of complex electrochemical corrosion dynamics. First, the relationship between the hydrogen gas volume fraction and the degree of moisture exposure exhibits significant nonlinear characteristics. For example, around the critical moisture threshold, the hydrogen generation rate may undergo a sudden change due to hydrolysis saturation of the water-blocking material or accumulation of corrosion products on the aluminum sheath. However, hydrogen detection cannot capture direct changes in moisture content, leading to misjudgment of the critical state. For example, when localized point moisture in the buffer layer and axial diffusion moisture produce the same hydrogen gas volume fraction, the former may enter the accelerated corrosion stage due to rapid moisture accumulation, while the latter remains in the slow penetration stage due to uniform moisture distribution. Relying solely on the hydrogen gas volume fraction cannot distinguish between these two distinct degradation modes, potentially leading to premature intervention or delayed maintenance decisions.

[0058] In response to the above technical problems, the embodiments of the present application provide a system and method for detecting the moisture content of the cable buffer layer of a high-voltage line. Combining dual-parameter detection of moisture and hydrogen, the moisture mass fraction in the buffer layer gas is determined by a metering device provided with a desiccant absorption layer, and its hygroscopic properties are used to achieve non-destructive in-situ monitoring. Simultaneously, a gas chromatograph is used to dynamically track the hydrogen gas integral fraction to accurately reflect the corrosion intensity. Based on multivariate linear regression analysis, the computer system establishes a dynamic correlation model of moisture and hydrogen, and captures the gas-water interaction laws at different moisture stages through historical data training. Compared with the traditional single-parameter threshold method, the embodiments of the present application can distinguish different moisture modes under the same hydrogen concentration, for example, combining the change in moisture gradient to judge local defects or overall degradation, and achieve accurate detection of the moisture content of the buffer layer.

[0059] The following specific embodiments describe in detail the technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0060] Figure 1 The schematic diagram of the structure of the buffer layer moisture degree detection system provided in the embodiment of the present application is as follows: Figure 1 As shown, the buffer layer moisture degree detection system 10 includes:

[0061] A gas collection component 11 is used to collect interstitial gas in the buffer layer;

[0062] A gas chromatograph 12, connected to the gas collection assembly 11, for analyzing the hydrogen peak area of ​​the interstitial gas;

[0063] A metering assembly 13, in which a dry absorbent layer is provided, for measuring the mass increment of the interstitial gas when it flows through the dry absorbent layer;

[0064] The computer system 14 is connected to both the gas chromatograph 12 and the metering component 11, and is used to determine the hydrogen volume fraction in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas; determine the water mass fraction in the interstitial gas based on the mass increment; and, based on the correlation between the moisture content of the buffer layer and the hydrogen volume fraction and the water mass fraction, determine the moisture content value of the buffer layer based on the hydrogen volume fraction and the water mass fraction.

[0065] Specifically, the gas collection component 11 can be a device such as a vacuum pump that can extract gas and ensure that there is no leakage during the gas collection and storage process.

[0066] When the buffer layer of a high-voltage cable becomes damp, it generates hydrogen. This is a process involving electrochemical corrosion. The core cause is that moisture creates an electrolyte environment between the metal sheath (usually aluminum or aluminum alloy) and the buffer layer material. Electrolytic corrosion occurs under the induced voltage generated by cable operation. A gas chromatograph can be used to detect the hydrogen content in the interstitial gas.

[0067] The gas chromatograph 12 utilizes chromatographic separation and detection techniques to perform qualitative and quantitative analysis on complex, multi-component mixtures. It typically consists of a gas flow system, a sample injection system, a separation system (chromatographic column system), a detection and temperature control system, and a recording system. The interstitial gas in the buffer layer, collected by the gas collection assembly 11, is injected into the gas chromatograph 12 to analyze the hydrogen peak area of ​​the interstitial gas.

[0068] The desiccant absorption layer in the metering component 13 contains a moisture adsorbent. For example, the moisture adsorbent is anhydrous calcium chloride particles, which is used to absorb moisture in the gap gas. The metering component 13 can measure the weight increase of the desiccant absorption layer after absorbing moisture.

[0069] The computer system 14 is a computer, workstation or server system with data processing capabilities. It can determine the hydrogen gas integral fraction and the water mass fraction in the gap gas based on the output results of the chromatograph 12 and the metering component 13, and further determine the moisture content of the buffer layer based on the hydrogen gas integral fraction and the water mass fraction.

[0070] In one embodiment, the computer system 14 determines the moisture level of the buffer layer based on a mapping relationship between the hydrogen gas volume fraction, the water mass fraction, and the moisture level of the buffer layer.

[0071] The buffer layer moisture degree detection system provided in the embodiment of the present application is provided with a gas collection component to detect the gap gas in the gap of the cable buffer layer, and a gas chromatograph and a metering component are provided to detect the hydrogen and moisture content in the gap gas respectively. Then, the computer system can accurately detect the moisture degree of the buffer layer from the two aspects of hydrogen content and moisture content, realize accurate early warning of moisture and identification of accelerated degradation trend, and provide key decision support for blocking the electrochemical corrosion chain reaction and improving the operation reliability of the cable.

[0072] In one possible implementation, the computer system, based on the correlation between the moisture level of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determines the moisture level of the buffer layer according to the hydrogen gas volume fraction and the water mass fraction, specifically is used to:

[0073] The hydrogen gas integral fraction and the water mass fraction are substituted into the moisture degree assessment model to obtain the moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas integral fraction and the water mass fraction.

[0074] For example, the moisture degree assessment model is shown as follows:

[0075]

[0076] Among them, F is the moisture degree of the buffer layer, C is the hydrogen gas volume fraction, and M is the water mass fraction. is a constant, is the linear regression coefficient, is the random error term.

[0077] In one embodiment, high-voltage cable sample data is obtained from a historical operating cable sample database, and a multivariate regression algorithm is used based on the high-voltage cable sample data to calculate the coefficients. 、 as well as . It is an error term that conforms to the normal distribution and is used to reflect the random compensation of the moisture degree value.

[0078] Optionally, high-voltage cable sample data in the historical cable sample database can be classified and statistically analyzed, and the moisture levels can be divided into grades based on the moisture levels. For example, four grades are established: 0 (dry), 1 (slightly damp), 2 (moderately damp), and 3 (severely damp). Each grade corresponds to a different moisture range. Based on the moisture range, the moisture level of the buffer layer is determined. By establishing a moisture level system, the moisture level of the buffer layer can be more intuitively displayed, making it easier for operation and maintenance personnel to take appropriate operation and maintenance measures based on the moisture level.

[0079] The buffer layer moisture level detection system provided in the embodiment of the present application is supported by a computer system that obtains high-voltage cable sample data from a historical operating cable sample database, and based on a moisture level assessment model, determines the moisture level of the buffer layer according to the hydrogen gas integral fraction and the water mass fraction, thereby achieving quantitative and accurate determination of the moisture level of the buffer layer from two dimensions: hydrogen and water.

[0080] In a possible implementation, the moisture degree assessment model is constructed in the following manner:

[0081] The high-voltage cable sample data is obtained, and the high-voltage cable sample data includes the hydrogen gas integral fraction, moisture mass fraction and moisture degree of the buffer layer of the high-voltage cable sample; based on the high-voltage cable sample data, a multivariate regression equation is fitted by the least squares method, and the multivariate regression equation is used to reflect the joint influence of the hydrogen gas integral fraction and the moisture mass fraction on the moisture degree of the buffer layer of the high-voltage cable; based on the multivariate regression equation, a random error term is set to obtain a moisture degree assessment model, and the random error term reflects the random compensation for the output result of the moisture degree assessment model.

[0082] First, establish the moisture degree assessment model as described in the above embodiment, substitute the n cable sample data into the moisture degree assessment model to obtain n samples. ,i=1,2,…,n. The sum of squares of the errors of each sample is:

[0083]

[0084] When dQ / dβ0=0, dQ / dβ1=0, and dQ / dβ2=0, the sum of squared errors reaches a minimum. Arranging them, we can obtain the following system of equations. Solving the equations yields the least squares estimates of β0, β1, and β2.

[0085]

[0086] The random error term conforms to the Gaussian distribution and is used to randomly compensate the output results of the moisture degree assessment model.

[0087] The buffer layer moisture degree detection system provided in the embodiment of the present application uses a computer system that dynamically analyzes data in combination with a multivariate linear regression model, effectively improving detection accuracy and overcoming the limitations of detection methods that rely solely on hydrogen. Secondly, an evaluation model constructed based on a historical database generates moisture level determination results in real time, and combined with visual reports, quickly guides operation and maintenance decisions, significantly enhancing timeliness. At the same time, non-destructive gas sampling is used to avoid damage to the cable structure and reduce detection costs. In addition, by monitoring changes in hydrogen gas volume fraction and moisture content, early warning of potential cable failures can be provided during the corrosion stage, reducing safety risks at the source, and providing data support for drying treatments, optimizing maintenance strategies, and extending cable life. This application combines multi-parameter fusion analysis, data-driven modeling, and engineering practicality, providing an efficient and reliable technical path for ensuring power system stability.

[0088] In one possible implementation, when determining the volume fraction of hydrogen gas in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas, the computer system is specifically configured to:

[0089] Determine the ratio of the hydrogen peak area in the standard gas to the hydrogen peak area in the gap gas; and multiply the ratio by the hydrogen volume fraction in the standard gas as the hydrogen volume fraction in the gap gas.

[0090] The standard gas refers to a standard gas with a known hydrogen gas volume fraction. By inputting the standard gas into a gas chromatograph, the hydrogen peak area of ​​the standard gas can be obtained.

[0091] Figure 2 Schematic diagram of a scenario in which a computer system analyzes hydrogen gas volume fractions according to an embodiment of the present application. Figure 2 As shown, the gas cylinder stores standard gas, and the standard gas is injected into the gas chromatograph to measure the hydrogen peak area in the standard gas. The gas storage bag stores gap gas, and the gap gas is injected into the gas chromatograph to measure the hydrogen peak area in the gap gas.

[0092] Assume that the peak area of ​​hydrogen in the standard gas measured by the gas chromatograph is The hydrogen peak area of ​​the interstitial gas is A, and the hydrogen gas volume fraction of the known standard gas is , then the hydrogen gas volume fraction in the gap gas can be determined according to the following formula:

[0093]

[0094] Where C is the volume fraction of hydrogen gas in the interstitial gas.

[0095] In the buffer layer moisture detection system provided in the embodiment of the present application, the computer system accurately determines the hydrogen volume fraction in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas measured by the gas chromatograph, and based on the relationship between the hydrogen volume fraction in the interstitial gas and the hydrogen peak area in the standard gas, the hydrogen volume fraction in the standard gas, and the hydrogen peak area of ​​the interstitial gas.

[0096] In one possible implementation, when determining the moisture mass fraction in the interstitial gas based on the mass increment, the computer system is specifically configured to:

[0097] The moisture mass fraction in the interstitial gas is obtained based on the ratio of the mass increment to the total amount of interstitial gas flowing through the dry absorbent layer.

[0098] For example, the process of measuring the moisture mass fraction in the gap gas is as follows:

[0099] Measuring Milligrams of anhydrous calcium chloride particles are used as moisture adsorbents and are loaded into the desiccant absorption layer in the metering component;

[0100] Use a flow pump to extract the interstitial gas and make it flow through the desiccant absorption layer. The extracted volume is V.

[0101] Detect the mass of anhydrous calcium chloride after adsorption of water, record it as ;

[0102] The computer system calculates the moisture mass fraction M in the gap gas using the following formula:

[0103]

[0104] The buffer layer moisture degree detection system provided in the embodiment of the present application fully utilizes the desiccant absorption layer to absorb moisture in the gap gas, and calculates the moisture mass fraction in the gap gas by measuring the weight increase of the desiccant absorption layer, thereby achieving the effect of simply and accurately measuring the moisture mass fraction in the gap gas.

[0105] In one possible embodiment, the gas collection assembly includes:

[0106] A vacuum pump, whose air inlet is connected to the air extraction valve and whose air outlet is connected to the sealed air bag, is used to extract the interstitial gas of the buffer layer into the sealed air bag through the air extraction valve, wherein the air extraction valve is set at the wave crest drilling of the aluminum sheath of the high-voltage cable.

[0107] Exemplarily, the process of collecting interstitial gas in the buffer layer using a vacuum pump is as follows:

[0108] First, use an electric drill and a gas valve to establish a gas channel at a preset position in the cable buffer layer. The preset position refers to the drilled hole at the crest of the aluminum sheath of the high-voltage cable.

[0109] Connect the air inlet of the vacuum pump to the air extraction valve, and the air outlet to the valve of the sealed air bag. The sealed air bag has airtightness to ensure that the gas will not leak during the gas collection and storage process;

[0110] Turn on the vacuum pump and extract the interstitial gas in the buffer layer into the sealed air bag through the air extraction valve.

[0111] The buffer layer moisture degree detection system provided in the embodiment of the present application is provided with a vacuum pump to collect the interstitial gas in the buffer layer, ensuring that the composition and concentration of the interstitial gas will not change during the collection process, providing a basis for accurate detection of the moisture degree of the buffer layer.

[0112] In a possible embodiment, a suction device is provided on the metering component, and the suction device is used to make the gap gas flow through the dry absorbent layer.

[0113] For example, Figure 3 This is a schematic diagram of a scenario where interstitial gas flows through a dry absorbent layer as provided in an embodiment of the present application. Figure 3 As shown, one end of the desiccant absorption layer is connected to the air storage bag, and the other end is connected to the exhaust device. The exhaust device starts to exhaust and extracts the gap gas stored in the air storage bag into the desiccant absorption layer. At the same time, the volume of the exhausted gas can be measured.

[0114] The buffer layer moisture degree detection system provided in the embodiment of the present application is provided with an air extraction device, so that the measurement of moisture in the gap gas is more convenient and accurate.

[0115] The embodiment of the present application further provides a method for detecting the moisture content of a buffer layer of a high-voltage cable, which is applied to a computer system in the buffer layer moisture content detection system in the above embodiment. Figure 4 A flow chart of a method for detecting moisture levels in a buffer layer of a high-voltage cable provided in an embodiment of the present application is shown as follows: Figure 4 As shown, the method for detecting the moisture degree of the buffer layer includes:

[0116] S401. Acquire in real time the hydrogen peak area of ​​the interstitial gas in the buffer layer of the high-voltage cable. The hydrogen peak area is obtained by analyzing with a gas chromatograph in a buffer layer moisture degree detection system.

[0117] When ambient moisture penetrates the buffer layer through cable seal defects, the water-blocking material in the polyester fiber absorbs water and hydrolyzes, causing volume expansion and structural loosening, resulting in localized high-resistance areas. Current is forced to concentrate in the aluminum sheath corrugations, triggering Joule heat accumulation and pyrolytic carbonization. Simultaneously, the moisture acts as an electrolyte, accelerating electrochemical corrosion of the aluminum sheath and generating gases such as hydrogen. Dynamically tracking the hydrogen gas volume fraction using a gas chromatograph accurately reflects the corrosion intensity.

[0118] S402 , obtaining in real time the mass increment of the gap gas collected when it flows through the metering component in the buffer layer moisture degree detection system.

[0119] The moisture mass fraction in the buffer layer gas is measured by a metering component, and its hygroscopic properties are utilized to achieve non-destructive in-situ monitoring. This is simpler than traditional resistivity measurement or white spot analysis, which requires power outage or destructive sampling.

[0120] S403 : Determine the hydrogen volume fraction in the interstitial gas according to the hydrogen peak area of ​​the interstitial gas.

[0121] Assume that the peak area of ​​hydrogen in the standard gas measured by the gas chromatograph is The hydrogen peak area of ​​the interstitial gas is A, and the hydrogen gas volume fraction of the known standard gas is , then the hydrogen gas volume fraction in the gap gas can be determined according to the following formula:

[0122]

[0123] Where C is the volume fraction of hydrogen gas in the interstitial gas.

[0124] S404. Determine the moisture mass fraction in the gap gas based on the mass increment.

[0125] For example, take Milligrams of anhydrous calcium chloride particles are used as moisture adsorbents and loaded into the desiccant absorption layer in the metering component; a flow pump is used to extract interstitial gas to flow through the desiccant absorption layer, and the extracted volume is recorded as V; the mass of anhydrous calcium chloride after the moisture adsorption is detected and recorded as The computer system calculates the moisture mass fraction M in the gap gas using the following formula:

[0126]

[0127] S405 , based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determine the moisture degree value of the buffer layer according to the hydrogen gas volume fraction and the water mass fraction.

[0128] The method for detecting the moisture degree of the buffer layer provided in the embodiment of the present application combines dual-parameter detection of moisture and hydrogen, determines the moisture mass fraction in the buffer layer gas through a metering device of the desiccant absorption layer, utilizes its hygroscopic characteristics to realize non-destructive in-situ monitoring, and simultaneously adopts a gas chromatograph to dynamically track the hydrogen gas integral fraction, accurately reflects the corrosion intensity and overcomes the limitation of a single indicator. Based on the correlation between the moisture degree of the buffer layer and the hydrogen gas integral fraction and the moisture mass fraction, the moisture degree value of the buffer layer is determined according to the hydrogen gas integral fraction and the moisture mass fraction, and the dynamic correlation between moisture and gas generation is quantified. It can distinguish different moisture modes under the same hydrogen concentration, for example, judge local defects or overall degradation in combination with the change in moisture gradient, realize accurate detection of the moisture degree of the buffer layer, and provide a basis for precise operation and maintenance.

[0129] In one possible implementation, based on the correlation between the moisture level of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determining the moisture level of the buffer layer according to the hydrogen gas volume fraction and the water mass fraction includes:

[0130] The hydrogen gas integral fraction and the water mass fraction are substituted into the moisture degree assessment model to obtain the moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas integral fraction and the water mass fraction.

[0131] For example, the moisture degree assessment model is shown as follows:

[0132]

[0133] Among them, F is the moisture degree of the buffer layer, C is the hydrogen gas volume fraction, and M is the water mass fraction. is a constant, is the linear regression coefficient, is the random error term.

[0134] In one embodiment, high-voltage cable sample data is obtained from a historical operating cable sample database, and a multivariate regression algorithm is used based on the high-voltage cable sample data to calculate the coefficients. 、 as well as . It is an error term that conforms to the normal distribution and is used to reflect the random compensation of the moisture degree value.

[0135] Optionally, high-voltage cable sample data from the historical cable sample database can be classified and statistically analyzed, with moisture levels divided into four levels based on moisture values. For example, four levels are established: 0 (dry), 1 (slightly damp), 2 (moderately damp), and 3 (severely damp). Each level corresponds to a different moisture range, and the moisture level of the buffer layer is determined based on this range. This moisture level system provides a more intuitive display of the moisture content of the buffer layer, making it easier for maintenance personnel to take appropriate measures based on the moisture level.

[0136] The method for detecting the moisture content of the buffer layer provided in the embodiment of the present application is supported by high-voltage cable sample data obtained from a historical operating cable sample database. Based on a moisture content assessment model, the moisture content of the buffer layer is determined according to the hydrogen gas integral fraction and the water mass fraction, thereby overcoming the defects caused by a single observation quantity and realizing accurate determination of the moisture content of the buffer layer from two dimensions of hydrogen and water.

[0137] Figure 5 This is a schematic diagram of the process of constructing a model for evaluating the degree of moisture in the buffer layer provided in the embodiment of the present application. Figure 5 As shown, in a possible implementation, the moisture degree assessment model is constructed in the following manner:

[0138] S501. Obtain high-voltage cable sample data, where the high-voltage cable sample data includes the hydrogen gas volume fraction, the water mass fraction, and the moisture degree of the buffer layer of the high-voltage cable sample.

[0139] S502. Based on historical operating cable sample data, a multivariate regression equation is fitted by the least squares method. The multivariate regression equation is used to reflect the combined effect of the hydrogen gas integral fraction and the water mass fraction on the moisture degree of the buffer layer of the high-voltage cable.

[0140] First, establish the buffer layer moisture degree evaluation model as described in the above embodiment, substitute n cable sample data into the buffer layer moisture degree evaluation model to obtain n samples ,i=1,2,…,n. The sum of squares of the errors of each sample is:

[0141]

[0142] When dQ / dβ0=0, dQ / dβ1=0, and dQ / dβ2=0, the sum of squared errors reaches a minimum. Arranging them, we can obtain the following system of equations. Solving the equations yields the least squares estimates of β0, β1, and β2.

[0143]

[0144] S503. Based on the multiple regression equation, a random error term is set to obtain a moisture degree assessment model, where the random error term reflects random compensation for the output result of the moisture degree assessment model.

[0145] The random error term conforms to the Gaussian distribution and is used to randomly compensate the output results of the moisture degree assessment model.

[0146] Some calculation examples are as follows: Using statistical analysis software to assist in analysis and calculation, we can get =-0.712, =0.08, =0.072. Refer to Table 1, where the determination coefficient R 2 =0.852 shows that the model has a good fitting effect; DW (Durbin-Watson statistic) = 2.111, the value is close to 2, indicating that the independence between each group of data is good and the model does not have autocorrelation; referring to Table 2, F = 43.318, which is much greater than the significance test requirement, indicating that the regression effect of the equation is highly significant; referring to Table 3, β1 and β2 are verified by t test, which verifies that the water mass fraction and H2 volume fraction are positively correlated with the moisture content of the buffer layer; the residual conforms to the normal distribution, which verifies the randomness of the sample. The distribution of the residual is as follows Figure 6 shown.

[0147]

[0148] The method for detecting the moisture content of the buffer layer provided in the embodiment of the present application uses a gas chromatograph to accurately separate hydrogen and a drying absorbent to quantitatively analyze moisture, and combines a multivariate linear regression model to dynamically analyze data, effectively improving detection accuracy; secondly, an evaluation model constructed based on a historical database generates moisture level determination results in real time, and combines visual reports to quickly guide operation and maintenance decisions, significantly enhancing timeliness, while avoiding cable structural damage and reducing detection costs through non-destructive gas sampling; in addition, by monitoring changes in hydrogen gas volume fraction and moisture content, early warning of potential cable failures can be provided during the corrosion stage, reducing safety risks at the source, and providing data support for drying treatment, optimizing maintenance strategies, and extending cable life. This application combines multi-parameter fusion analysis, data-driven modeling, and engineering practicality, providing an efficient and reliable technical path for ensuring power system stability.

[0149] In addition to the above-mentioned embodiments, the present application also provides a method for detecting the moisture content of the buffer layer. By embedding a sensing optical fiber into the cable buffer layer, the distributed changes in temperature and strain can be sensed in real time to indirectly detect the moisture content of the cable buffer layer. When moisture invades the buffer layer, the mechanical stress generated by the hydrolysis and expansion of the polyester fiber will cause abnormal local strain of the optical fiber, while the Joule heat generated by electrochemical corrosion will cause the temperature gradient to rise. By establishing a thermal-mechanical coupling model, the moisture content of the cable buffer layer can be distinguished: for example, local point moisture will form a high strain area accompanied by a temperature rise lag due to limited expansion, while axial diffusion moisture will manifest as a uniform rise in the temperature field and low strain accumulation. This solution does not require the destruction of the cable structure and can achieve simultaneous analysis of multiple parameters through a single optical fiber, but it is necessary to solve the problem of mechanical compatibility between the optical fiber and the buffer layer material.

[0150] Figure 7 This is a schematic diagram of the structure of a device for detecting the moisture content of a buffer layer of a high-voltage cable provided in this application. This embodiment of the application provides a device for detecting the moisture content of a buffer layer of a high-voltage cable, which is applied to a computer system in a buffer layer moisture content detection system as described in various possible implementations of the embodiment. The buffer layer moisture content detection device 70 includes:

[0151] An acquisition module 701 is configured to acquire in real time the hydrogen peak area of ​​the interstitial gas in the buffer layer of the high-voltage cable, the hydrogen peak area being obtained by gas chromatograph analysis in the buffer layer moisture degree detection system; and to acquire in real time the mass increment of the interstitial gas collected when it flows through the metering component in the buffer layer moisture degree detection system;

[0152] Determination module 702 is used to determine the hydrogen gas volume fraction in the gap gas based on the hydrogen peak area of ​​the gap gas; determine the water mass fraction in the gap gas based on the mass increment; based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, determine the moisture degree value of the buffer layer based on the hydrogen gas volume fraction and the water mass fraction.

[0153] In a possible implementation, the determining module 702 is specifically configured to:

[0154] The hydrogen gas integral fraction and the water mass fraction are substituted into the moisture degree assessment model to obtain the moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas integral fraction and the water mass fraction.

[0155] In a possible implementation, the buffer layer moisture degree detection device 70 further includes a model building module for:

[0156] Obtaining high-voltage cable sample data, the high-voltage cable sample data including the hydrogen gas volume fraction, moisture mass fraction, and buffer layer moisture degree of the high-voltage cable sample;

[0157] Based on historical operating cable sample data, a multivariate regression equation was fitted using the least squares method. The multivariate regression equation is used to reflect the combined effect of hydrogen gas volume fraction and water mass fraction on the moisture content of the buffer layer of high-voltage cables.

[0158] Based on the multiple regression equation, random error terms are set to obtain the moisture degree assessment model. The random error terms reflect the random compensation for the output results of the moisture degree assessment model.

[0159] The device for detecting moisture content of a buffer layer of a high-voltage cable provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effects are similar and will not be described in detail in this embodiment.

[0160] Figure 8 This is a schematic diagram of the structure of the device for detecting the moisture content of the buffer layer of a high-voltage cable provided in this application. Figure 8 As shown, the device 80 for detecting moisture levels in a buffer layer of a high-voltage cable provided in this embodiment includes at least one processor 801 and a memory 802. Optionally, the device 80 also includes a communication interface 803. The processor 801, the memory 802, and the communication interface 803 are connected via a communication bus 804.

[0161] During the specific implementation process, at least one processor 801 executes the computer-executable instructions stored in the memory 802, so that the at least one processor 801 performs the above method.

[0162] The specific implementation process of the processor 801 can be found in the above method embodiment. Its implementation principle and technical effects are similar and will not be repeated here in this embodiment.

[0163] The device for detecting the moisture level of the buffer layer of the high-voltage cable may be the computer system in the above embodiment.

[0164] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly executed by a hardware processor or by a combination of hardware and software modules in the processor.

[0165] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage.

[0166] A bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be categorized as address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0167] An embodiment of the present application also provides a computer program product, including a computer program, which implements the above method when executed.

[0168] An embodiment of the present application further provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed, the above-mentioned method is implemented.

[0169] The readable storage medium may be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0170] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in a device as discrete components.

[0171] The division of units is merely a logical functional division; actual implementations may employ alternative divisions, such as combining or integrating multiple units or components into another system, or omitting or disabling certain features. Furthermore, any direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units, either through an interface, electrical, mechanical, or other means.

[0172] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0173] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0174] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the method of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical disks.

[0175] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0176] Finally, it should be noted that those skilled in the art will readily identify other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The present invention is not limited to the precise structure described above and illustrated in the accompanying drawings, and various modifications and variations may be made without departing from the scope thereof. The scope of the present invention is limited solely by the appended claims.

Claims

1. A system for detecting moisture content of a buffer layer of a high-voltage cable, characterized in that: include: A gas collection component, used for collecting interstitial gas in the buffer layer; a gas chromatograph, connected to the gas collection assembly, for analyzing the hydrogen peak area of ​​the interstitial gas; a metering component, wherein a dry absorbent layer is provided, for measuring the mass increment when the interstitial gas flows through the dry absorbent layer; a computer system connected to the gas chromatograph and the metering component, and configured to determine the hydrogen volume fraction in the interstitial gas based on the hydrogen peak area of ​​the interstitial gas; determining a water mass fraction in the interstitial gas according to the mass increment; Furthermore, based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, the moisture degree value of the buffer layer is determined according to the hydrogen gas volume fraction and the water mass fraction.

2. The buffer layer moisture degree detection system according to claim 1, characterized in that: The computer system is specifically configured to determine the moisture level of the buffer layer based on the correlation between the moisture level of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, according to the hydrogen gas volume fraction and the water mass fraction: The hydrogen gas volume fraction and the water mass fraction are substituted into a moisture degree assessment model to obtain a moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas volume fraction and the water mass fraction.

3. The buffer layer moisture degree detection system according to claim 2, characterized in that: The moisture degree assessment model is constructed in the following way: Acquiring high-voltage cable sample data, wherein the high-voltage cable sample data includes a hydrogen gas volume fraction, a water mass fraction, and a degree of moisture in a buffer layer of the high-voltage cable sample; Based on the high-voltage cable sample data, a multivariate regression equation is fitted by the least squares method, wherein the multivariate regression equation is used to reflect the combined effect of the hydrogen gas volume fraction and the water mass fraction on the moisture degree of the buffer layer of the high-voltage cable; Based on the multiple regression equation, a random error term is set to obtain the moisture degree assessment model, and the random error term reflects the random compensation for the output result of the moisture degree assessment model.

4. The buffer layer moisture degree detection system according to any one of claims 1 to 3, characterized in that: When determining the volume fraction of hydrogen gas in the interstitial gas according to the hydrogen peak area of ​​the interstitial gas, the computer system is specifically configured to: Determining the ratio of the hydrogen peak area in the standard gas to the hydrogen peak area in the interstitial gas; The product of the ratio and the hydrogen gas volume fraction in the standard gas is used as the hydrogen gas volume fraction in the gap gas.

5. The buffer layer moisture degree detection system according to any one of claims 1 to 3, characterized in that: When determining the moisture mass fraction in the interstitial gas according to the mass increment, the computer system is specifically configured to: The moisture mass fraction in the interstitial gas is obtained according to the ratio of the mass increment to the total amount of interstitial gas flowing through the dry absorbent layer.

6. The buffer layer moisture degree detection system according to any one of claims 1 to 3, characterized in that: The gas collection component comprises: A vacuum pump, whose air inlet is connected to the air extraction valve and whose air outlet is connected to the sealed air bag, is used to extract the interstitial gas of the buffer layer into the sealed air bag through the air extraction valve, wherein the air extraction valve is arranged at the wave crest drilling of the aluminum sheath of the high-voltage cable.

7. The buffer layer moisture degree detection system according to any one of claims 1 to 3, characterized in that: The metering assembly is provided with an exhaust device, through which the interstitial gas is made to flow through the dry absorbent layer.

8. A method for detecting the moisture level of a buffer layer of a high-voltage cable, characterized in that: A computer system applied to a buffer layer moisture degree detection system according to any one of claims 1 to 7, wherein the buffer layer moisture degree detection method comprises: Real-time acquisition of the hydrogen peak area of ​​the interstitial gas in the buffer layer of the high-voltage cable, wherein the hydrogen peak area is obtained by gas chromatograph analysis in the buffer layer moisture degree detection system; Real-time acquisition of mass increments collected when the gap gas flows through a metering component in the buffer layer moisture degree detection system; determining a hydrogen volume fraction in the interstitial gas according to a hydrogen peak area of ​​the interstitial gas; determining a water mass fraction in the interstitial gas according to the mass increment; Based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction, the moisture degree value of the buffer layer is determined according to the hydrogen gas volume fraction and the water mass fraction.

9. The method for detecting the moisture degree of the buffer layer according to claim 8, characterized in that: The determining of the moisture degree of the buffer layer based on the correlation between the moisture degree of the buffer layer and the hydrogen gas volume fraction and the water mass fraction according to the hydrogen gas volume fraction and the water mass fraction includes: The hydrogen gas volume fraction and the water mass fraction are substituted into a moisture degree assessment model to obtain a moisture degree value of the buffer layer. The moisture degree assessment model reflects the correlation between the moisture degree value and the hydrogen gas volume fraction and the water mass fraction.

10. The method for detecting the moisture degree of the buffer layer according to claim 9, characterized in that: The moisture degree assessment model is constructed in the following way: Acquiring high-voltage cable sample data, wherein the high-voltage cable sample data includes a hydrogen gas volume fraction, a water mass fraction, and a degree of moisture in a buffer layer of the high-voltage cable sample; Based on the historical operating cable sample data, a multivariate regression equation is fitted by the least squares method, where the multivariate regression equation is used to reflect the combined effect of the hydrogen gas volume fraction and the water mass fraction on the moisture degree of the buffer layer of the high-voltage cable; Based on the multiple regression equation, a random error term is set to obtain the moisture degree assessment model, and the random error term reflects the random compensation for the output result of the moisture degree assessment model.

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