A method, device and equipment for predicting the aging life of high-voltage submarine cable insulation

Abstract

The present invention relates to the technical field of high-voltage AC cable insulation, and provides a method, device, and equipment for predicting the aging life of a high-voltage submarine cable insulation, comprising: obtaining environmental data and cable breakdown time of a cable sample; the environmental data including the electric field, temperature, and mechanical stress applied by the environment to the cable sample; calculating the characteristic breakdown time corresponding to the cable sample using a Weibull distribution according to the cable breakdown time of the cable sample; establishing a high-voltage submarine cable insulation aging life prediction model using the environmental data and characteristic breakdown time of the cable sample; obtaining environmental data of the cable to be predicted in an actual application environment, and calculating the insulation aging life of the cable to be predicted using the prediction model, thereby enabling efficient and accurate prediction of the cable life under a multi-physics composite field.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage AC cable insulation, and in particular to a method, device and equipment for predicting the aging life of high-voltage submarine cable insulation. Background Art

[0002] my country has proposed a major strategy to develop tens of millions of kilowatts of offshore wind power, and the current voltage level of high-voltage submarine cables has reached 500kV. Therefore, it is very critical to ensure the reliable operation of high-voltage submarine cables, that is, it is necessary to predict the insulation aging life under the combined action of multiple physical fields.

[0003] The insulation of high-voltage submarine cables ages under the combined effects of electric, thermal, and mechanical stresses. Due to the complex nature of these multiple physical fields, the aging patterns are complex, making lifespan assessment difficult. Based on the aging characteristics of insulation, domestic and international scholars have proposed several empirical models to describe the aging patterns of insulation materials, such as the inverse power model, exponential model, Arrhenius model, and RAMU model. However, the above models also show significant deficiencies in the application process. For example, the inverse power model and the Arrhenius model can only describe the aging process under the action of single factors of electric field and thermal field. When the electric and thermal factors are applied to the insulation material at the same time, its aging life is significantly shortened, resulting in the inverse power model and the Arrhenius model being unable to accurately describe the actual life of high-voltage AC cable insulation; the background of the RAMU model is based on the inverse power function law of the classic single stress electrical aging, and the constant of the inverse power function law is set as a coefficient related to temperature, so as to describe the joint influence of electric field and temperature on the insulation aging life. However, the evaluation error of this model is large, and there is a problem of a small scope of application, making it difficult to accurately evaluate the insulation aging life of high-voltage AC cables; further, few people have studied the influence of mechanical stress on the insulation aging life, and even less so the insulation aging life under the combined action of electric field, thermal field and mechanical stress. Summary of the Invention

[0004] The present invention provides a method for predicting the insulation aging life of a high-voltage submarine cable, which is used to solve the problem of inaccurate life assessment of high-voltage submarine cables in the prior art.

[0005] A first aspect of the present invention provides a method for predicting the insulation aging life of a high-voltage submarine cable, comprising:

[0006] Obtaining environmental data and cable breakdown time of the cable sample; the environmental data includes the electric field, temperature, and mechanical stress exerted by the environment on the cable sample;

[0007] According to the cable breakdown time of the cable sample, the characteristic breakdown time corresponding to the cable sample is calculated using Weibull distribution;

[0008] A high-voltage submarine cable insulation aging life prediction model was established based on the environmental data and characteristic breakdown time of cable samples;

[0009] Environmental data of the cable to be predicted in an actual application environment is obtained, and the insulation aging life of the cable to be predicted is calculated using the prediction model.

[0010] Optionally, the characteristic breakdown time corresponding to each group of cable samples is calculated using Weibull distribution according to the cable breakdown time of the cable samples, specifically by fitting the cable breakdown time in the cable samples to obtain a corresponding Weibull distribution model, wherein the Weibull distribution model is:

[0011]

[0012] Where P is the breakdown probability, α is the scale factor of the breakdown time, β is the shape factor of the breakdown time, and t is the breakdown time;

[0013] According to the preset breakdown probability, the characteristic breakdown time corresponding to the cable sample is obtained using the Weibull distribution model.

[0014] Optionally, the environmental data and characteristic breakdown time of the cable samples are used to establish a high-voltage submarine cable insulation aging life prediction model, specifically:

[0015] Substituting the environmental data and characteristic breakdown time of n groups of cable samples into the electrothermal-mechanical composite field cable insulation aging life coefficient model, respectively, and establishing a high-voltage submarine cable insulation aging life prediction model based on the coefficient model; n is an integer not less than 6, and at least one item of the environmental data of each group of cable samples is different;

[0016] The insulation aging life coefficient model of the electrothermal mechanical composite field cable is specifically:

[0017]

[0018] Among them, E0, T0, M0, E1, T1, and M1 are the electric field strength, temperature, and mechanical stress of the environment in which the two groups of cable samples are located, respectively. L0 is the insulation life under the conditions of electric field strength E0, temperature T0, and mechanical stress M0. L1 is the insulation life under the conditions of electric field strength E1, temperature T1, and mechanical stress M1. E0 , L T0 , L M0 are the insulation life under the single factors of electric field intensity E0, temperature T0 and mechanical stress M0, L E1 , L T1 , L M1are the insulation life under the action of single factors of electric field intensity E1, temperature T1 and mechanical stress M1, and G is the correlation coefficient between electric field, temperature and mechanical stress.

[0019] Optionally, L is determined using the electric field insulation life model based on the values ​​of the electric field strengths E0 and E1. E0 With L E1 Ratio, the electric field insulation life model is specifically:

[0020]

[0021] Wherein, h is the aging coefficient under the single action of electric field;

[0022] According to the value of temperature T0, L is determined by the temperature insulation life model. T0 With L T1 Ratio, the temperature insulation life model is specifically:

[0023]

[0024] Wherein, k is the aging coefficient under the single effect of temperature;

[0025] According to the values ​​of mechanical stress M0 and M1, L is determined by the mechanical stress insulation life model. M0 With L M1 Ratio, the mechanical stress insulation life model is specifically:

[0026]

[0027] Where m is the aging coefficient under the single action of mechanical stress.

[0028] Optionally, the value of G is determined by an electrothermal-mechanical multi-physics field correlation coefficient model according to the values ​​of the electric field intensities E0 and E1, the temperature T, and the mechanical stresses M0 and M1. The electrothermal-mechanical multi-physics field correlation coefficient model is specifically:

[0029]

[0030] Where n, n′, and n″ are the correlation coefficients between electric field and temperature, electric field and mechanical stress, and temperature and mechanical stress, respectively.

[0031] Optionally, the establishment of a high-voltage submarine cable insulation aging life prediction model based on the coefficient model is specifically as follows:

[0032] The values ​​of coefficients h, k, m, n, n′ and n″ are calculated according to the coefficient model, and a high-voltage submarine cable insulation aging life prediction model is established using the coefficients;

[0033] The high-voltage submarine cable insulation aging life prediction model is specifically as follows:

[0034]

[0035] Where L is the predicted insulation aging life of the high-voltage submarine cable to be predicted, and E, T, and M are the electric field strength, temperature, and mechanical stress of the actual application environment of the submarine cable to be predicted, respectively.

[0036] Optionally, the environmental data of the cable sample is obtained as follows:

[0037] Obtain the setting parameters of the electric field constant temperature box where the cable sample is located and the mechanical stress device installed on the cable sample.

[0038] Optionally, in the electric field constant temperature box, the temperature range that can be set is 50-150° C., the electric field strength range is 40-80 kV / mm, and the tensile and compressive stress range that can be applied by the mechanical stress device is 0-10 MPa.

[0039] A second aspect of the present application provides a device for predicting the insulation aging life of a high-voltage submarine cable, comprising:

[0040] The cable sample experiment module is used to obtain the environmental data of the cable sample and the cable breakdown time; the environmental data includes the electric field, temperature and mechanical stress applied by the environment to the cable sample;

[0041] A characteristic breakdown time calculation module is used to calculate the characteristic breakdown time corresponding to the cable sample using Weibull distribution according to the cable breakdown time of the cable sample;

[0042] The cable insulation aging life prediction model establishment module is used to establish a high-voltage submarine cable insulation aging life prediction model based on the environmental data and characteristic breakdown time of cable samples;

[0043] The cable insulation aging life prediction module is used to obtain environmental data of the cable to be predicted in an actual application environment and calculate the insulation aging life of the cable to be predicted using the prediction model.

[0044] A third aspect of the present application provides a device for predicting the aging life of a high-voltage submarine cable insulation, the device comprising a processor and a memory:

[0045] The memory is used to store program code and transmit the program code to the processor;

[0046] The processor is used to execute the high-voltage submarine cable insulation aging life prediction method described in any one of the first aspects of the present invention according to the instructions in the program code.

[0047] It can be seen from the above technical solutions that the present invention has the following advantages: by obtaining the environmental data and cable breakdown time of the cable sample; the environmental data includes the electric field, temperature and mechanical stress applied by the environment to the cable sample; according to the cable breakdown time of the cable sample, the characteristic breakdown time corresponding to the cable sample is calculated using the Weibull distribution; a high-voltage submarine cable insulation aging life prediction model is established using the environmental data and characteristic breakdown time of the cable sample; the environmental data of the cable to be predicted in the actual application environment is obtained, and the insulation aging life of the cable to be predicted is calculated using the prediction model. The characteristic breakdown time calculated by the Weibull distribution describes the life characteristics of the cable under multiple physical fields, and the life prediction model reflects the law of change of the insulation aging life of the cable under the joint action of multiple physical fields such as electric field, temperature and mechanical stress, and can efficiently and accurately predict the life of the cable in the actual application environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0049] Figure 1 This is a flow chart of the method for predicting the aging life of high-voltage submarine cable insulation;

[0050] Figure 2 This is a flow chart for calculating the characteristic breakdown time of the high-voltage submarine cable insulation aging life prediction method;

[0051] Figure 3 Establish a flow chart for the prediction model of high-voltage submarine cable insulation aging life prediction method;

[0052] Figure 4 This is the flow chart of the electric thermal field experiment for the high-voltage submarine cable insulation aging life prediction method;

[0053] Figure 5 This is the overall flow chart of the method for predicting the aging life of high-voltage submarine cable insulation;

[0054] Figure 6 Diagram of the device for predicting the aging life of high-voltage submarine cable insulation. DETAILED DESCRIPTION

[0055] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0056] The present invention provides a method for predicting the insulation aging life of a high-voltage submarine cable, which is used to solve the problem of inaccurate life assessment of high-voltage submarine cables in the prior art.

[0057] See also Figure 1 , Figure 1 Flowchart of a method for predicting the insulation aging life of a high-voltage submarine cable provided in an embodiment of the present invention.

[0058] S100, obtaining environmental data and cable breakdown time of a cable sample; the environmental data including electric field, temperature, and mechanical stress applied by the environment to the cable sample;

[0059] It should be noted that this example first exposes the cable sample to a combined electric field, temperature, and mechanical stress field. The electric field strength, temperature, and mechanical stress applied to the cable sample are simultaneously controlled to maintain constant values ​​at preset values. Environmental data for the cable sample, namely the field strength, temperature, and stress values, is then acquired. The cable breakdown time required for the cable sample to break down in this multi-physics combined field is then recorded.

[0060] S200, calculating a characteristic breakdown time corresponding to the cable sample using Weibull distribution according to the cable breakdown time of the cable sample;

[0061] It should be noted that the cable breakdown time of the cable samples is fitted into a double-coefficient Weibull distribution curve, and the corresponding characteristic breakdown time of the group of cable samples under the electrothermal data is obtained using the Weibull distribution.

[0062] S300: Establish a high-voltage submarine cable insulation aging life prediction model based on the environmental data and characteristic breakdown time of cable samples;

[0063] It should be noted that this embodiment combines the characteristic breakdown times obtained when the cable samples are subjected to the simultaneous action of voltage, temperature and mechanical stress to establish a high-voltage submarine cable insulation aging life prediction model that reflects the influence of the three on the insulation life.

[0064] S400: Acquire environmental data of the cable to be predicted in an actual application environment, and calculate the insulation aging life of the cable to be predicted using the prediction model.

[0065] It should be noted that the high-voltage submarine cable insulation aging life prediction model reflects the influence of electric field, temperature and mechanical stress on the insulation aging life. The electric field strength, temperature and mechanical stress of the cable application environment to be predicted need to be substituted into the model for calculation to obtain the corresponding insulation aging life.

[0066] In this example, the characteristic breakdown time of cable samples is first calculated using a Weibull distribution. A high-voltage submarine cable insulation aging lifespan prediction model is then established. Finally, the environmental data of the cable to be predicted is substituted to calculate its insulation aging lifespan. The characteristic breakdown time calculated using the Weibull distribution describes the cable's characteristics under electrothermal fields. The lifespan prediction model reflects the variation in the cable's insulation aging lifespan under the combined effects of electric fields, temperature, and mechanical stress, enabling efficient and accurate prediction of cable lifespan under corresponding multi-physics composite fields.

[0067] The above is a detailed description of the first embodiment of a method for predicting the insulation aging life of a high-voltage submarine cable provided by this application. The following is a detailed description of the second embodiment of a method for predicting the insulation aging life of a high-voltage submarine cable provided by this application.

[0068] Reference Figure 2 , Figure 2 This is a flow chart of the characteristic breakdown time calculation method for predicting the aging life of high-voltage submarine cable insulation. In step S200 of the aforementioned embodiment, the characteristic breakdown time corresponding to the cable sample is calculated using the Weibull distribution based on the cable breakdown time of the cable sample, specifically:

[0069] S210, fitting the cable breakdown time in the cable sample to obtain a corresponding Weibull distribution model;

[0070] It should be noted that the Weibull distribution model is:

[0071]

[0072] Among them, P is the breakdown probability, α is the scale coefficient of the breakdown time, β is the shape coefficient of the breakdown time, and t is the breakdown time; the number of samples in each group of cable samples is 5-10, and the breakdown times of multiple cables in the same group are fitted into a double-coefficient Weibull distribution. The scale coefficient α and the shape coefficient β of the breakdown time are obtained, and the Weibull distribution model corresponding to this group of cable samples is obtained.

[0073] Furthermore, in this embodiment, the number of samples in each group of cable samples is 5-10 to improve the efficiency of Weibull distribution fitting. In actual prediction experiments, the number of samples in each group of cable samples can be selected to be greater than 10. In this way, the more cables in each group of cable samples, the more breakdown times are obtained for fitting, and the more accurate the Weibull distribution obtained by fitting.

[0074] S220 , according to the preset breakdown probability, obtain the characteristic breakdown time corresponding to the cable sample using a Weibull distribution model.

[0075] It should be noted that, in this embodiment, the preset breakdown probability is 63.2%, which corresponds to the average life of the cable, that is, the mathematical expectation of the cable life in the Weibull distribution.

[0076] Reference Figure 3 , Figure 3 A flow chart for establishing a prediction model for the high-voltage submarine cable insulation aging life prediction method is provided. In step S300 of the aforementioned embodiment, the high-voltage submarine cable insulation aging life prediction model is established based on the electrothermal data and characteristic breakdown time of the cable sample, specifically:

[0077] S310, establish an insulation aging life coefficient model for electric thermal mechanical composite field cables;

[0078] The insulation aging life coefficient model of the electrothermal mechanical composite field cable is specifically:

[0079]

[0080] Among them, E0, T0, M0, E1, T1, and M1 are the electric field strength, temperature, and mechanical stress of the environment in which the two groups of cable samples are located, respectively. L0 is the insulation life under the conditions of electric field strength E0, temperature T0, and mechanical stress M0. L1 is the insulation life under the conditions of electric field strength E1, temperature T1, and mechanical stress M1. E0 , L T0 、L M0 are the insulation life under the single factors of electric field intensity E0, temperature T0 and mechanical stress M0, L E1 、L T1 、L M1 are the insulation life under the action of single factors of electric field intensity E1, temperature T1 and mechanical stress M1, and G is the correlation coefficient between electric field, temperature and mechanical stress;

[0081] It should be noted that the insulation life under the action of a single factor refers to the insulation life when only the electric field strength, temperature or mechanical stress changes, while other environmental parameters do not change. It can be understood that the insulation life under the action of a single factor needs to rely on the data of two groups of cable samples to reflect, that is, it needs to be measured at LE0 With L E1 The ratio of L T0 With L T1 The ratio of L M0 With L M1 The influence of a single factor can be reflected only when the ratio is .

[0082] Furthermore, the insulation life affected by multiple single factors can also predict the insulation aging life of the cable. The value of G can be calculated first based on the insulation life of the cable samples affected by six groups of single factors and two groups of multi-physical fields. Then, the single factors of each physical field of the multi-physical composite field of the cable to be predicted are retained, and the three insulation lives affected by the single factors of its actual application environment are calculated. Combined with the insulation life of the cable samples affected by the other three groups of single factors and one group of multi-physical factors, the insulation aging life of the cable to be predicted under the multi-physical composite field can be calculated.

[0083] S320, calculating a coefficient value using a coefficient model according to a single factor insulation life model, a multi-physics field correlation coefficient model, and environmental parameters;

[0084] It should be noted that according to the values ​​of the electric field strength E0 and E1, the electric field insulation life model is used to determine L E0 With L E1 Ratio, the electric field insulation life model is specifically:

[0085]

[0086] According to the value of temperature T0, L is determined by the temperature insulation life model. T0 With L T1 Ratio, the temperature insulation life model is specifically:

[0087]

[0088] According to the values ​​of mechanical stress M0 and M1, L is determined by the mechanical stress insulation life model. M0 With L M1 Ratio, the mechanical stress insulation life model is specifically:

[0089]

[0090] According to the values ​​of electric field strength E0 and E1, temperature T, and mechanical stress M0 and M1, the value of G is determined by the electrothermal-mechanical multi-physics field correlation coefficient model. The electrothermal-mechanical multi-physics field correlation coefficient model is specifically:

[0091]

[0092] Wherein, h is the aging coefficient under the single action of electric field, k is the aging coefficient under the single action of temperature, m is the aging coefficient under the single action of mechanical stress, n, n′ and n″ are the correlation coefficients between electric field and temperature, electric field and mechanical stress, and temperature and mechanical stress, respectively.

[0093] Finally, the insulation aging life coefficient model of the electrothermal mechanical composite field cable is obtained as follows:

[0094]

[0095] S330, calculating the values ​​of coefficients h, k, m, n, n′, and n″ according to the coefficient model, and establishing a high-voltage submarine cable insulation aging life prediction model using the coefficients;

[0096] The high-voltage submarine cable insulation aging life prediction model is specifically as follows:

[0097]

[0098] Where L is the predicted insulation aging life of the high-voltage submarine cable to be predicted, and E, T, and M are the electric field strength, temperature, and mechanical stress of the actual application environment of the submarine cable to be predicted, respectively.

[0099] In this embodiment, the characteristic breakdown time of cable samples is calculated using the Weibull distribution. A cable insulation aging life coefficient model for an electrothermal-mechanical composite field is then established. Using the individual insulation life models, the multi-physics field correlation coefficient model, and environmental parameters, the coefficients are calculated to establish a high-voltage submarine cable insulation aging life prediction model that reflects the influence of the three factors of electrothermal and mechanical factors on insulation aging life. The characteristic breakdown time calculated using the Weibull distribution describes the cable's characteristics under an electrothermal field. The life prediction model reflects the variation in the cable's insulation aging life under the combined effects of voltage and temperature, optimizing the model calculations and enabling efficient and accurate prediction of the cable's life under the corresponding multi-physics composite field.

[0100] The above is a detailed description of the second embodiment of a method for predicting the insulation aging life of a high-voltage submarine cable provided by this application. The following is a detailed description of the third embodiment of a method for predicting the insulation aging life of a high-voltage submarine cable provided by this application.

[0101] Reference Figure 4 , Figure 4 This is a flow chart of an electric thermal field experiment for a method for predicting the aging life of high-voltage submarine cable insulation. In step S100 of the aforementioned embodiment, environmental data of the cable sample and the cable breakdown time are obtained. The environmental data includes the electric field, temperature, and mechanical stress applied to the cable sample by the environment, and specifically includes:

[0102] S110 uses a flat vulcanizing press to prepare high-voltage AC cable samples, the temperature and pressure of insulation cross-linking, simulates the manufacturing process of high-voltage AC cables, and removes cross-linking byproducts after manufacturing.

[0103] It should be noted that the cable sample obtained in this embodiment is a flat-plate vulcanizing machine that simulates the cable to be predicted, and a flat-plate sample is made of the insulation material of the cable to be predicted. This makes it easier to obtain electrothermal data and cable breakdown time, as well as to perform subsequent life prediction. In actual predictions, the same cable entity as the cable to be predicted can also be used to calculate electrothermal data and cable breakdown time. In this embodiment, the cross-linking temperature set on the flat-plate vulcanizing machine is 180°C, the pressure is 15MPa, the manufacturing process lasts 15 minutes, and the diameter of the prepared cable sample is 50mm. After the manufacturing is completed, the cable sample is placed in a 60°C vacuum drying oven and left to stand for more than 24 hours to remove cross-linking by-products.

[0104] S120: installing the cable sample on a mechanical stress device, setting mechanical stress, and then placing the cable sample in an electric field constant temperature box while maintaining the stress state;

[0105] It should be noted that in order to simulate the water pressure received by the submarine cable in seawater, the mechanical stress device applies uniform pressure between the upper and lower surfaces of the flat cable sample to simulate the seawater pressure state. Different groups of cable samples are set with different tensile and compressive stresses, and the tensile and compressive stresses that can be applied by the mechanical stress device range from 0 to 10 MPa.

[0106] Furthermore, the electrodes in the electric field constant temperature box are cylindrical metal electrodes, and the chamfer radius ranges from 0.5 to 1 mm. In this embodiment, the electrodes used are brass cylindrical electrodes with a diameter of 25 mm and a chamfer radius of 1 mm; the temperature range of the electric field constant temperature box is 50 to 150°C, and the electric field strength range is 40 to 80 kV / mm.

[0107] S130: applying a constant electric field to the cable samples of different groups until the cable samples break down, and recording environmental data and cable breakdown time.

[0108] It should be noted that before the experiment begins, the cable samples are placed in an electric field constant temperature box, and the temperature of the constant temperature box is adjusted to the experimental temperature. The temperature is kept stable for at least 30 minutes so that the electrodes and samples reach a constant experimental temperature. The electric field strength, temperature and mechanical stress of the environment in which the cable samples are located are maintained until the cable samples break down. The environmental parameters corresponding to each group of cable samples and the cable breakdown time are recorded.

[0109] For further information, see Figure 5 , Figure 5 This is the overall flow chart of the high-voltage submarine cable insulation aging life prediction method. Figure 5The steps in the embodiment can refer to the corresponding process in the aforementioned embodiment and will not be repeated here.

[0110] In this embodiment, after processing multiple groups of cable samples, mechanical stress is first applied to simulate the seabed pressure state, and then they are placed in different electric field constant temperature boxes to apply temperature and electric field, so as to establish an electrothermal mechanical multi-physical composite field for the cable samples, and the corresponding cable breakdown time is calculated, which provides data for coefficient calculation in subsequent steps. This data reflects the change law of the insulation aging life of the cable under the joint action of voltage, temperature and mechanical stress, and can efficiently and accurately predict the life of the cable under the corresponding multi-physical composite field.

[0111] The above is a detailed description of the third embodiment of a high-voltage submarine cable insulation aging life prediction method provided by this application. The following is a detailed description of a high-voltage submarine cable insulation aging life prediction device provided by the second aspect of this application.

[0112] See also Figure 6 , Figure 6 This embodiment provides a device for predicting the insulation aging life of a high-voltage submarine cable under a multi-physics composite field, which is characterized by comprising:

[0113] The cable sample experiment module 10 is used to obtain environmental data of the cable sample and the cable breakdown time; the environmental data includes the electric field, temperature and mechanical stress applied by the environment to the cable sample;

[0114] a characteristic breakdown time calculation module 20 for calculating the characteristic breakdown time corresponding to the cable sample using Weibull distribution according to the cable breakdown time of the cable sample;

[0115] The cable insulation aging life prediction model establishment module 30 is used to establish a high-voltage submarine cable insulation aging life prediction model based on the environmental data and characteristic breakdown time of the cable sample;

[0116] The cable insulation aging life prediction module 40 is used to obtain environmental data of the cable to be predicted in an actual application environment, and calculate the insulation aging life of the cable to be predicted using the prediction model.

[0117] The third aspect of the present application also provides a high-voltage submarine cable insulation aging life prediction device, including a processor and a memory: the memory is used to store program code and transmit the program code to the processor; the processor is used to execute the above-mentioned high-voltage submarine cable insulation aging life prediction method according to the instructions in the program code.

[0118] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and equipment can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0119] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0120] The units described as separate components may or may not be physically separate, and the 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.

[0121] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0122] If the integrated unit is implemented in the form of 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 part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0123] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for predicting the aging life of high-voltage submarine cable insulation, characterized in that: include: Obtain environmental data and cable breakdown time of cable samples; The environmental data include electric field, temperature and mechanical stress imposed on the cable sample by the environment; According to the cable breakdown time of the cable sample, the characteristic breakdown time corresponding to the cable sample is calculated using Weibull distribution; A high-voltage submarine cable insulation aging life prediction model was established based on the environmental data and characteristic breakdown time of cable samples; Obtaining environmental data of the cable to be predicted in an actual application environment, and calculating the insulation aging life of the cable to be predicted using the prediction model; The high-voltage submarine cable insulation aging life prediction model is established based on the environmental data and characteristic breakdown time of the cable samples, specifically: Substituting the environmental data and characteristic breakdown time of n groups of cable samples into the electrothermal-mechanical composite field cable insulation aging life coefficient model, respectively, and establishing a high-voltage submarine cable insulation aging life prediction model based on the coefficient model; n is an integer not less than 6, and at least one item of the environmental data of each group of cable samples is different; The insulation aging life coefficient model of the electrothermal mechanical composite field cable is specifically: Among them, E0, T0, M0, E1, T1, and M1 are the electric field strength, temperature, and mechanical stress of the environment in which the two groups of cable samples are located, respectively. L0 is the insulation life under the conditions of electric field strength E0, temperature T0, and mechanical stress M0. L1 is the insulation life under the conditions of electric field strength E1, temperature T1, and mechanical stress M1. E0 、L T0 、L M0 are the insulation life under the single factors of electric field intensity E0, temperature T0 and mechanical stress M0, L E1 、L T1 、L M1 are the insulation life under the action of single factors of electric field intensity E1, temperature T1 and mechanical stress M1, and G is the correlation coefficient between electric field, temperature and mechanical stress; According to the values ​​of electric field strength E0 and E1, L is determined by the electric field insulation life model. E0 With L E1 The electric field insulation life model is specifically: Wherein, h is the aging coefficient under the single action of electric field; According to the value of temperature T0, L is determined by the temperature insulation life model. T0 With L T1 The temperature insulation life model is specifically: Wherein, k is the aging coefficient under the single effect of temperature; According to the values ​​of mechanical stress M0 and M1, L is determined by the mechanical stress insulation life model. M0 With L M1 The mechanical stress insulation life model is specifically: Wherein, m is the aging coefficient under the single action of mechanical stress; According to the values ​​of electric field strength E0 and E1, temperature T, and mechanical stress M0 and M1, the value of G is determined by the electrothermal-mechanical multi-physics field correlation coefficient model. The electrothermal-mechanical multi-physics field correlation coefficient model is specifically: Among them, n, n′ and n″ are the correlation coefficients between electric field and temperature, electric field and mechanical stress, and temperature and mechanical stress, respectively; The high-voltage submarine cable insulation aging life prediction model established according to the coefficient model is specifically as follows: The values ​​of coefficients h, k, m, n, n′ and n″ are calculated according to the coefficient model, and a high-voltage submarine cable insulation aging life prediction model is established using the coefficients; The high-voltage submarine cable insulation aging life prediction model is specifically as follows: Where L is the predicted insulation aging life of the high-voltage submarine cable to be predicted, and E, T, and M are the electric field strength, temperature, and mechanical stress of the actual application environment of the submarine cable to be predicted, respectively.

2. A method for predicting the insulation aging life of a high-voltage submarine cable according to claim 1, characterized in that: According to the cable breakdown time of the cable samples, the characteristic breakdown time corresponding to each group of cable samples is calculated using Weibull distribution, specifically: the cable breakdown time in the cable samples is fitted to obtain the corresponding Weibull distribution model, and the Weibull distribution model is: Where P is the breakdown probability, α is the scale factor of the breakdown time, β is the shape factor of the breakdown time, and t is the breakdown time; According to the preset breakdown probability, the characteristic breakdown time corresponding to the cable sample is obtained using the Weibull distribution model.

3. A method for predicting the insulation aging life of a high-voltage submarine cable according to claim 1, characterized in that: The environmental data of the cable sample are specifically obtained as follows: Obtain the setting parameters of the electric field constant temperature box where the cable sample is located and the mechanical stress device installed on the cable sample.

4. A method for predicting the insulation aging life of a high-voltage submarine cable according to claim 3, characterized in that: In the electric field constant temperature box, the temperature range that can be set is 50-150° C., the electric field strength range is 40-80 kV / mm, and the tensile and compressive stress range that can be applied by the mechanical stress device is 0-10 MPa.

5. A device for predicting the insulation aging life of a high-voltage submarine cable, characterized in that: include: Cable sample experiment module, used to obtain environmental data and cable breakdown time of cable samples; The environmental data include electric field, temperature and mechanical stress imposed on the cable sample by the environment; A characteristic breakdown time calculation module is used to calculate the characteristic breakdown time corresponding to the cable sample using Weibull distribution according to the cable breakdown time of the cable sample; The cable insulation aging life prediction model establishment module is used to establish a high-voltage submarine cable insulation aging life prediction model based on the environmental data and characteristic breakdown time of cable samples; A cable insulation aging life prediction module is used to obtain environmental data of the cable to be predicted in an actual application environment and calculate the insulation aging life of the cable to be predicted using the prediction model; The high-voltage submarine cable insulation aging life prediction model is established based on the environmental data and characteristic breakdown time of the cable samples, specifically: Substituting the environmental data and characteristic breakdown time of n groups of cable samples into the electrothermal-mechanical composite field cable insulation aging life coefficient model, respectively, and establishing a high-voltage submarine cable insulation aging life prediction model based on the coefficient model; n is an integer not less than 6, and at least one item of the environmental data of each group of cable samples is different; The insulation aging life coefficient model of the electrothermal mechanical composite field cable is specifically: Among them, E0, T0, M0, E1, T1, and M1 are the electric field strength, temperature, and mechanical stress of the environment in which the two groups of cable samples are located, respectively. L0 is the insulation life under the conditions of electric field strength E0, temperature T0, and mechanical stress M0. L1 is the insulation life under the conditions of electric field strength E1, temperature T1, and mechanical stress M1. E0 , L T0 , L M0 are the insulation life under the action of single factors of electric field intensity E0, temperature T0 and mechanical stress M0, L E1 , L T1 , L M1 are the insulation life under the action of single factors of electric field intensity E1, temperature T1 and mechanical stress M1, and G is the correlation coefficient between electric field, temperature and mechanical stress; According to the values ​​of electric field strength E0 and E1, L is determined by the electric field insulation life model. E0 With L E1 The electric field insulation life model is specifically: Wherein, h is the aging coefficient under the single action of electric field; According to the value of temperature T0, L is determined by the temperature insulation life model. T0 With L T1 The temperature insulation life model is specifically: Wherein, k is the aging coefficient under the single effect of temperature; According to the values ​​of mechanical stress M0 and M1, L is determined by the mechanical stress insulation life model. M0 With L M1 The mechanical stress insulation life model is specifically: Wherein, m is the aging coefficient under the single action of mechanical stress; According to the values ​​of electric field strength E0 and E1, temperature T, and mechanical stress M0 and M1, the value of G is determined by the electrothermal-mechanical multi-physics field correlation coefficient model. The electrothermal-mechanical multi-physics field correlation coefficient model is specifically: Among them, n, n′ and n″ are the correlation coefficients between electric field and temperature, electric field and mechanical stress, and temperature and mechanical stress, respectively; The high-voltage submarine cable insulation aging life prediction model established according to the coefficient model is specifically as follows: The values ​​of coefficients h, k, m, n, n′ and n″ are calculated according to the coefficient model, and a high-voltage submarine cable insulation aging life prediction model is established using the coefficients; The high-voltage submarine cable insulation aging life prediction model is specifically as follows: Where L is the predicted insulation aging life of the high-voltage submarine cable to be predicted, and E, T, and M are the electric field strength, temperature, and mechanical stress of the actual application environment of the submarine cable to be predicted, respectively.

6. A high-voltage submarine cable insulation aging life prediction device, characterized in that: The device includes a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the high-voltage submarine cable insulation aging life prediction method according to any one of claims 1 to 4 according to the instructions in the program code.

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