Lossless discrimination method, device and equipment for weight-reducing mass of cable conductor and medium

Abstract

The embodiment of the invention discloses a lossless discrimination method, device and equipment for the weight-reducing mass of a cable conductor, and a medium, and the method comprises the steps: measuring a first impedance spectrum of a to-be-detected cable in an open-circuit state, and measuring a second impedance spectrum of the to-be-detected cable in a short-circuit state in a preset frequency range; the characteristic impedance of the to-be-detected cable is obtained based on the first impedance spectrum and the second impedance spectrum, and the characteristic impedance comprises a real part and an imaginary part; determining a characteristic peak frequency vector of the to-be-detected cable and a peak vector of the to-be-detected cable corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance; acquiring pre-measured characteristic impedance of the standard cable in a preset frequency range; based on the imaginary part of the standard characteristic impedance, determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector; on the basis of the peak vector of the to-be-detected cable and the peak vector of the standard cable, the weight-reducing mass of the to-be-detected cable conductor is judged, and the weight-reducing mass is used for judging whether the sectional area of the to-be-detected cable conductor is reduced or not.

Description

Technical Field

[0001] The present invention relates to the field of computer technology, and more particularly to a method, device, equipment and medium for non-destructive determination of the weight loss quality of a cable conductor. Background Art

[0002] As a transmission medium, cables are widely used in power transmission in modern urban distribution networks. In recent years, with the continuous increase in their usage, cable conductor quality problems have gradually been exposed. Some distribution cables use qualified copper conductors within a range of about ten meters at the end, but in the middle of the cable, about a hundred meters, the number of single wires or the cross-sectional area are reduced, that is, "conductor slimming" is used to reduce costs and make illegal profits. Conventional quality inspections are difficult to identify such problems and assess their severity. This type of cable with conductor slimming quality problems not only causes huge economic losses to power users, but is also prone to hidden dangers such as overheating and overloading, accelerates local aging of the cable, and in severe cases even threatens the safe and stable operation of the distribution network.

[0003] At present, the problem of conductor slimming in the middle section of such cables can only be checked through destructive methods, while conventional detection methods for cable defects such as oscillation wave partial discharge method, ultra-low frequency ULF (Ultra Low Frequency) partial discharge method, ultra-low frequency dielectric loss detection and time domain reflection method are mainly based on high-voltage excitation methods, which have a certain risk of cumulative insulation damage. Summary of the invention

[0004] One or more embodiments of the present specification provide a method, device, equipment and medium for non-destructive determination of the slimming quality of a cable conductor, which is used to solve the technical problems raised by the background technology.

[0005] One or more embodiments of this specification adopt the following technical solutions:

[0006] One or more embodiments of this specification provide a non-destructive determination method for the slimming quality of a cable conductor, the method comprising:

[0007] Within a preset frequency range, measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state;

[0008] Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part;

[0009] Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0010] Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range;

[0011] Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0012] The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

[0013] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0014] Nondestructive testing: The embodiments of this specification can realize nondestructive testing of cables, avoiding physical damage to the cables that may be caused by traditional destructive testing methods, thereby protecting the integrity of the cables.

[0015] Slimming quality judgment: The embodiments of this specification can determine whether the cross-sectional area of ​​the cable conductor is reduced, that is, the conductor is slimmed, which is crucial for evaluating the safety and reliability of the cable.

[0016] Improved safety: The embodiments of this specification can prevent power outages and safety accidents caused by cable faults by timely discovering and handling conductor slimming problems, thereby improving the safe and stable operation of the distribution network.

[0017] Furthermore, obtaining the characteristic impedance of the cable to be tested based on the first impedance spectrum and the second impedance spectrum includes:

[0018] By formula The characteristic impedance of the cable to be tested is obtained, where Z0 is the characteristic impedance of the cable to be tested, and Z open For the first impedance spectrum, Z short is the second impedance spectrum.

[0019] Further, the determining of the characteristic peak frequency vector of the cable to be inspected and the peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance includes:

[0020] Based on the imaginary part of the characteristic impedance, determining a peak curve that varies with the test frequency within the preset frequency range;

[0021] The characteristic peak frequency vector of the cable to be inspected and the peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector are determined in the peak vector curve.

[0022] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0023] Improve detection efficiency: Determine the peak curve within the preset frequency range, which can quickly screen out the key frequency points in the cable, thereby improving detection efficiency.

[0024] Enhanced diagnostic capabilities: The determination of characteristic peak frequency vectors and peak vectors enhances diagnostic capabilities, allowing inspectors to more accurately assess the quality and performance of the cable.

[0025] Furthermore, the step of determining the weight loss quality of the conductor of the cable to be inspected based on the peak vector of the cable to be inspected and the peak vector of the standard cable includes:

[0026] Determine a first root mean square value of the peak vector of the cable to be tested, and determine a second root mean square value of the peak vector of the standard cable;

[0027] Based on the first root mean square value and the second root mean square value, the weight loss quality of the cable conductor to be inspected is determined.

[0028] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0029] Improved accuracy: By comparing the RMS value of the cable under test with the standard cable, it is possible to more accurately determine whether the cable conductor has become thinner, because the RMS value can reflect the overall fluctuation amplitude of the signal.

[0030] Further, determining a first root mean square value of the peak vector of the cable to be tested, and determining a second root mean square value of the peak vector of the standard cable, comprises:

[0031] By formula Determine a first root mean square value of the peak vector of the cable to be inspected, wherein rmsBy′ is the first root mean square value of the peak vector of the cable to be inspected, and b′(f(i)) is the peak vector of the cable to be inspected;

[0032] By formula Determine a second root mean square value of the peak vector of the standard cable, wherein rmsBy is the second root mean square value of the peak vector of the standard cable, b(f(i)) is the peak vector of the standard cable, and n is a constant greater than 0.

[0033] Further, judging the weight loss quality of the cable conductor to be inspected based on the first root mean square value and the second root mean square value includes:

[0034] Based on the ratio of the first root mean square value to the second root mean square value, the weight loss quality of the cable conductor to be inspected is determined.

[0035] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0036] Accurate weight loss quality judgment: By comparing the ratio of the first RMS value to the second RMS value, it is possible to more accurately determine whether the cable conductor has been weight-lossed, because the change in the ratio can reflect the change in the cable cross-sectional area.

[0037] Further, judging the weight loss quality of the cable conductor to be inspected based on the ratio of the first root mean square value to the second root mean square value includes:

[0038] By judging the condition rmsBy′ / rmsBy≥K ， Performing weight loss quality judgment on the cable to be inspected, wherein K is a weight loss quality evaluation parameter set based on the preset frequency range;

[0039] If rmsBy′ / rmsBy≥K, it is determined that the cable to be inspected has a thin quality.

[0040] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0041] Clear evaluation criteria: By setting a preset frequency range and the corresponding evaluation parameter K, a clear quality evaluation criterion for cable quality is provided, which helps to unify and standardize cable quality evaluation.

[0042] One or more embodiments of this specification provide a non-destructive determination device for the weight loss quality of a cable conductor, comprising:

[0043] An impedance spectrum measuring unit, which measures a first impedance spectrum of the cable to be tested in an open circuit state and a second impedance spectrum of the cable to be tested in a short circuit state within a preset frequency range;

[0044] A characteristic impedance determining unit, which obtains a characteristic impedance of the cable to be tested based on the first impedance spectrum and the second impedance spectrum, wherein the characteristic impedance includes a real part and an imaginary part;

[0045] A first vector determination unit, which determines a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0046] A characteristic impedance acquisition unit, which acquires the characteristic impedance of the standard cable within the preset frequency range measured in advance;

[0047] A second vector determination unit, which determines the peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0048] The slimming quality judging unit judges the slimming quality of the conductor of the cable to be tested based on the peak vector of the cable to be tested and the peak vector of the standard cable, wherein the slimming quality is used to determine whether the cross-sectional area of ​​the conductor of the cable to be tested is reduced.

[0049] One or more embodiments of this specification provide a non-destructive determination device for the weight loss quality of a cable conductor, including:

[0050] at least one processor; and,

[0051] a memory communicatively connected to the at least one processor; wherein,

[0052] The memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0053] Within a preset frequency range, measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state;

[0054] Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part;

[0055] Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0056] Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range;

[0057] Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0058] The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

[0059] One or more embodiments of this specification provide a non-volatile computer storage medium storing computer executable instructions, which can achieve the following when executed by a computer:

[0060] Within a preset frequency range, respectively measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state;

[0061] Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part;

[0062] Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0063] Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range;

[0064] Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0065] The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

[0066] At least one of the above technical solutions adopted in the embodiments of this specification can achieve the following beneficial effects:

[0067] Nondestructive testing: The embodiments of this specification can realize nondestructive testing of cables, avoiding physical damage to the cables that may be caused by traditional destructive testing methods, thereby protecting the integrity of the cables.

[0068] Slimming quality judgment: The embodiments of this specification can determine whether the cross-sectional area of ​​the cable conductor is reduced, that is, the conductor is slimmed, which is crucial for evaluating the safety and reliability of the cable.

[0069] Improved safety: The embodiments of this specification can prevent power outages and safety accidents caused by cable faults by timely discovering and handling conductor slimming problems, thereby improving the safe and stable operation of the distribution network. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] In order to more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art description. Obviously, the drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. In the drawings:

[0071] Figure 1 A flow chart of a method for non-destructive determination of cable conductor weight loss quality provided in one or more embodiments of this specification;

[0072] Figure 2 A schematic diagram of a curve showing a change in the imaginary part of characteristic impedance versus test frequency provided in one or more embodiments of this specification;

[0073] Figure 3A schematic diagram of a curve showing a change in the imaginary part of characteristic impedance versus test frequency provided in one or more embodiments of this specification;

[0074] Figure 4 A schematic diagram of the structure of a non-destructive determination device for the weight loss quality of a cable conductor provided in one or more embodiments of this specification;

[0075] Figure 5 A schematic diagram of the structure of a non-destructive determination device for the slimming quality of a cable conductor provided in one or more embodiments of this specification. DETAILED DESCRIPTION

[0076] The embodiments of this specification provide a method, device, equipment and medium for non-destructive determination of the slimming quality of cable conductors.

[0077] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this specification.

[0078] Figure 1 A schematic diagram of a process flow of a non-destructive determination method of cable conductor weight loss quality provided in one or more embodiments of this specification, which process can be executed by a cable conductor weight loss quality determination system. Certain input parameters or intermediate results in the process allow manual intervention and adjustment to help improve accuracy.

[0079] The method steps of the embodiment of this specification are as follows:

[0080] S101, within a preset frequency range, measuring a first impedance spectrum at the beginning of the cable when the end of the cable to be tested is in an open circuit state, and measuring a second impedance spectrum at the beginning of the cable when the end of the cable to be tested is in a short circuit state.

[0081] In the embodiments of this specification, the preset frequency range can be set based on actual conditions. The impedance spectrum refers to a curve of the cable impedance with respect to the signal frequency, which can include an amplitude spectrum and a phase spectrum. The first impedance spectrum and the second impedance spectrum can be measured using a network analyzer or a spectrum analyzer.

[0082] S102: Obtain a characteristic impedance of the cable to be inspected based on the first impedance spectrum and the second impedance spectrum, where the characteristic impedance includes a real part and an imaginary part.

[0083] In the embodiment of this specification, the formula The characteristic impedance of the cable to be tested is obtained, where Z0 is the characteristic impedance of the cable to be tested, and Z open For the first impedance spectrum, Z short is the second impedance spectrum.

[0084] It should be noted that the characteristic impedance Z0 refers to the impedance encountered when electromagnetic waves propagate between conductors and insulators. The characteristic impedance Z0 is an important parameter because the characteristic impedance Z0 determines the reflection and attenuation of the signal when it is transmitted in the cable. The characteristic impedance is a complex number and can be expressed as Z0=R0+jX0, where R0 is the real part, representing the resistance, which is related to the resistivity, length and cross-sectional area of ​​the material; j is the imaginary unit, and X0 is the imaginary part, representing the reactance, which is usually composed of capacitance (C) and inductance (L).

[0085] S103: Determine, based on the imaginary part of the characteristic impedance, a characteristic peak frequency vector of the cable to be inspected and an imaginary part peak vector of the characteristic impedance of the cable to be inspected corresponding to the characteristic peak frequency vector.

[0086] In an embodiment of the present specification, a peak curve that changes with the test frequency can be first determined within the preset frequency range based on the imaginary part of the characteristic impedance; finally, the characteristic peak frequency vector of the cable to be tested and the peak vector of the cable to be tested corresponding to the characteristic peak frequency vector can be determined in the peak vector curve.

[0087] It should be noted that the above content can be implemented through the following specific implementation plans:

[0088] The imaginary part values ​​of characteristic impedance at multiple frequency points are plotted into a curve, i.e., a peak curve. Characteristic peak frequencies are identified in the peak curve, and these frequencies correspond to the points where the imaginary part of the characteristic impedance reaches a maximum value. These characteristic peak frequency points are recorded to form a characteristic peak frequency vector. For each characteristic peak frequency, the corresponding peak value of the cable to be tested is determined in the peak curve, and the peak values ​​of the cables to be tested are recorded to form a peak vector of the cable to be tested.

[0089] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0090] Improve detection efficiency: Determine the peak curve within the preset frequency range, which can quickly screen out the key frequency points in the cable, thereby improving detection efficiency.

[0091] Enhanced diagnostic capabilities: The determination of characteristic peak frequency vectors and peak vectors enhances diagnostic capabilities, allowing inspectors to more accurately assess the quality and performance of the cable.

[0092] S104, obtaining the pre-measured characteristic impedance of the standard cable within the preset frequency range.

[0093] S105: Determine the peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance.

[0094] It should be noted that the standard cable is a standard cable with known performance. The characteristic impedance of the standard cable and the peak vector of the standard cable corresponding to the characteristic peak frequency vector are generated in advance.

[0095] S106, based on the peak vector of the cable to be inspected and the peak vector of the standard cable, determining the weight loss mass of the conductor of the cable to be inspected, wherein the weight loss mass is used to determine whether there is a reduction in the cross-sectional area of ​​the conductor of the middle section of the cable to be inspected.

[0096] In an embodiment of the present specification, when judging the slimming quality of the conductor of the cable to be tested based on the peak vector of the cable to be tested and the peak vector of the standard cable, a first root mean square value of the peak vector of the cable to be tested and a second root mean square value of the peak vector of the standard cable can be determined first; based on the first root mean square value and the second root mean square value, the slimming quality of the conductor of the cable to be tested is judged.

[0097] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0098] Improved accuracy: By comparing the RMS value of the cable under test with the standard cable, it is possible to more accurately determine whether the cable conductor has become thinner, because the RMS value can reflect the overall fluctuation amplitude of the signal.

[0099] Furthermore, when determining the first RMS value of the peak vector of the cable to be tested and the second RMS value of the peak vector of the standard cable, the formula Determine the first root mean square value of the peak vector of the cable to be tested, wherein rmsBy′ is the first root mean square value of the peak vector of the cable to be tested, and b′(f(i)) is the peak vector of the cable to be tested; by formula Determine a second root mean square value of the peak vector of the standard cable, wherein rmsBy is the second root mean square value of the peak vector of the standard cable, b(f(i)) is the peak vector of the standard cable, and n is a constant greater than 0.

[0100] Furthermore, when judging the weight loss quality of the cable conductor to be inspected based on the first root mean square value and the second root mean square value, the weight loss quality of the cable conductor to be inspected can be judged based on the ratio of the first root mean square value to the second root mean square value.

[0101] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0102] Accurate weight loss quality judgment: By comparing the ratio of the first RMS value to the second RMS value, it is possible to more accurately determine whether the cable conductor has been weight-lossed, because the change in the ratio can reflect the change in the cable cross-sectional area.

[0103] Furthermore, when judging the weight loss quality of the cable conductor to be inspected based on the ratio of the first root mean square value to the second root mean square value, the judgment condition rmsBy′ / rmsBy≥K ， The slimming quality of the cable to be inspected is judged, wherein K is a slimming quality evaluation parameter set based on the preset frequency range; if rmsBy′ / rmsBy≥K, it is determined that the cable to be inspected has slimming quality; if rmsBy′ / rmsBy is less than K, it is determined that the cable to be inspected does not have slimming quality.

[0104] In addition, the embodiments of this specification can also evaluate the slimming quality of the cable conductor based on the ratio of the first root mean square value to the second root mean square value, that is, when the ratio of the first root mean square value to the second root mean square value is in different threshold ranges, the severity of the conductor slimming can be obtained.

[0105] It should be noted that the embodiments of this specification have the following beneficial effects through the above contents:

[0106] Clear evaluation criteria: By setting a preset frequency range and the corresponding evaluation parameter K, a clear quality evaluation criterion for cable quality is provided, which helps to unify and standardize cable quality evaluation.

[0107] It should be noted that at present, the problem of cable middle section conductor weight loss can only be checked by destructive methods, and conventional cable defect detection methods such as oscillation wave partial discharge method, ultra-low frequency ULF (Ultra Low Frequency) partial discharge method, ultra-low frequency dielectric loss detection and time domain reflection method are mainly based on high-voltage excitation methods, which have a certain risk of cumulative insulation damage. Although they can diagnose cable faults, they cannot detect the discontinuous and slight changes in the cross-sectional area of ​​the cable conductor. In addition, the severity of cable conductor weight loss is related to the degree of economic loss of users, and there is no non-destructive and convenient evaluation method. Therefore, it is necessary to study a method for non-destructive identification of cable conductor weight loss quality problems and its severity assessment.

[0108] It should be noted that the embodiments of this specification aim at the practical problem that it is difficult to non-destructively identify and evaluate the slimming quality problem of cable conductors, and the technical solution adopted is: a method for non-destructively identifying the slimming quality problem of cable conductors and evaluating their severity. Based on the analysis of the impedance spectrum characteristics when the cable has a slimming quality problem of the conductor, the impedance spectrum of the head end of the cable to be tested is measured in two states: open circuit and short circuit. The characteristic impedance of the cable to be tested is calculated, and its imaginary part is taken. A curve of the change of the imaginary part of the characteristic impedance with respect to the frequency is plotted, and the characteristic peak frequency of the curve is extracted. The root mean square value of the imaginary part of the characteristic impedance at the characteristic peak frequency is calculated, and compared with the root mean square value of the imaginary part of the characteristic impedance at the characteristic peak frequency of a normal cable of the same model. Combined with the conductor slimming severity assessment table, it can be determined whether the conductor of the cable to be tested has a conductor slimming quality problem and its severity.

[0109] It should be noted that the impedance spectrum at the head end refers to the curve of the complex impedance at the head end of the cable with respect to the signal frequency, including the amplitude spectrum and the phase spectrum. When the load at the end of the cable is in the short-circuit and open-circuit states respectively, the impedance spectrum at the head end is recorded as Z short and Z open , then the characteristic impedance Z0 of the cable can be calculated by the following formula:

[0110]

[0111] If the cable to be tested is a cable with conductor slimming quality problems, the measured impedance spectra of the first end in the short-circuit and open-circuit states are Z short ' and Z open ', the result obtained by the above formula (1) is recorded as the characteristic impedance Z0' of the cable in question.

[0112] The imaginary part of the characteristic impedance Z0' of the cable to be tested is recorded as b', and the imaginary part of the characteristic impedance Z0 of a normal cable of the same specification (i.e., the standard cable mentioned above) is recorded as b. Plot the curve of b' versus test frequency, and take its peak frequency vector as Bx', and the peak vector as By', as shown in the following equations (2) and (3):

[0113] Bx' = [f(1), f(2), ..., f(n)], where n is the number of peak points (2);

[0114] By' = [b'(f(1)), b'(f(2)), ..., b'(f(n))], where n is the number of peak points (3);

[0115] The imaginary vector of the characteristic impedance Z0 of a normal cable of the same specification and model at the peak frequency is By, as shown in the following formula (4):

[0116] By = [b(f(1)), b(f(2)), ..., b(f(n))], where n is the number of peak points (4);

[0117] Calculate the RMS value of the imaginary part of the characteristic impedance of the cable under test and the normal cable of the same specification and model at the characteristic peak frequency, as shown in the following equations (5) and (6):

[0118]

[0119] If rmsBy' is 50 times or more of rmsBy, it is judged that the cable under test has a conductor slimming quality problem, that is, the judgment condition is:

[0120] α=rmsBy' / rmsBy≥50(7);

[0121] After the ratio α is calculated, the severity of the cable conductor slimming to be tested is evaluated by the conductor slimming severity evaluation table in Table 1. The severity is divided into three levels: low, medium, and high, corresponding to the cross-sectional area of ​​the cable conductor being reduced by less than 10%, reduced by 10% to 20%, and reduced by more than 20%, respectively. The range of the ratio α is also related to the upper limit of the test frequency. The table gives the empirical value of the ratio α in the range of 10MHz to 50MHz. The empirical values ​​of other frequency ranges can be obtained by interpolation.

[0122] Table 1 Conductor slimming severity assessment table

[0123]

[0124] Furthermore, the embodiments of this specification also provide a method for non-destructive identification of cable conductor weight loss quality problems and severity assessment, and the specific implementation methods are as follows:

[0125] like Figure 2 The schematic diagram of the conductor slimming cable model shown in the figure shows that when the conductor in the middle section of the cable has a conductor slimming problem, it is assumed that the starting and ending positions of the conductor slimming part are la and lb respectively. Since the cross-section of the conductor in the middle section is discontinuous, the local distributed parameters R, L, G, and C will change, and the change in the distributed parameters will further cause the local characteristic impedance to change.

[0126] A 50m long conductor slim cable is customized. The 10m sections at both ends use copper conductor cables with a conductor cross-sectional area of ​​95mm2, and the middle 30m section uses copper conductor cables with a conductor cross-sectional area of ​​70mm2, i.e. la = 10m and lb = 40m, and the total cable length is l = 50m. Calculation shows that the conductor cross-sectional area of ​​the middle section of the customized cable is reduced by 26.3%.

[0127] First, the impedance spectrum Z of a normal copper conductor cable of the same specification and model and 50m in length is measured when the end is short-circuited and open-circuited. short and Z open The upper limit of the test frequency is 50MHz. The characteristic impedance Z0 is calculated by formula (1), and its imaginary part is recorded as b.

[0128] Then the impedance spectrum Z of the first end of the customized conductor slim cable is measured when the end is short-circuited and open-circuited. short ' and Z open ', the upper limit of the test frequency is 50MHz, and the characteristic impedance Z0' is calculated by formula (1), and its imaginary part is recorded as b'. Figure 3 The diagram shows the curve of the imaginary part of characteristic impedance changing with the test frequency.

[0129] It can be seen that the imaginary part of the characteristic impedance of the cable to be tested has 20 peak points, that is, n=20.

[0130] From the frequency curve, we can get the peak frequency vector:

[0131] Bx'=[1830000, 3860000, 5990000, 8020000, 11710000, 13740000,

[0132] 15850000,17880000,21590000,23620000,25730000,27760000,31470000,

[0133] 33500000,35600000,37630000,41350000,43380000,45480000,47510000]

[0134] Peak vector:

[0135] By'=[-100.7608,-53.5294,+46.3785,+64.6093,-59.3647,-36.9097,

[0136] +35.0411,+52.3441,-49.8372,-31.1640,+30.3114,+46.1570,-44.6628,

[0137] -27.8334,+27.3884,+42.3409,-41.1929,-25.5416,+25.2370,+39.3756]

[0138] Find the imaginary part vector of the characteristic impedance Z0 of a normal cable of the same specification and model at the peak frequency:

[0139] By=[-0.1375,-0.0949,-0.0762,-0.0659,-0.0546,-0.0504,

[0140] -0.0469,-0.0442,-0.0402,-0.0384,-0.0368,-0.0355,-0.0333,

[0141] -0.0323,-0.0313,-0.0305,-0.0291,-0.0284,-0.0277,-0.0271]

[0142] The RMS values ​​of the imaginary part of the characteristic impedance of the tested cable and the normal cable of the same specification and model at the characteristic peak frequency are calculated by equations (5) and (6) as follows: rmsBy'=47.1968, rmsBy=0.0551 respectively.

[0143] The ratio α=rmsBy' / rmsBy=856.6>>50 is calculated by formula (7), which indicates that the tested cable has a conductor slimming quality problem.

[0144] From Table 1, it can be seen that the severity assessment result of the slimming quality problem of the cable conductor under test is high, and the cross-sectional area of ​​the conductor is reduced by more than 20%, which is consistent with the actual situation.

[0145] At this point, the non-destructive identification of the slimming quality problems of the cable conductor under test and the assessment of its severity have been achieved.

[0146] Figure 4 A schematic structural diagram of a non-destructive determination device for the slimming quality of a cable conductor provided for one or more embodiments of the present specification, comprising: an impedance spectrum measurement unit 401, a characteristic impedance determination unit 402, a first vector determination unit 403, a characteristic impedance acquisition unit 404, a second vector determination unit 405 and a slimming quality determination unit 406.

[0147] The impedance spectrum measuring unit 401 measures a first impedance spectrum of the cable to be tested in an open circuit state and a second impedance spectrum of the cable to be tested in a short circuit state within a preset frequency range;

[0148] A characteristic impedance determining unit 402 is configured to obtain a characteristic impedance of the cable to be tested based on the first impedance spectrum and the second impedance spectrum, wherein the characteristic impedance includes a real part and an imaginary part;

[0149] A first vector determining unit 403 determines a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0150] A characteristic impedance acquisition unit 404 is configured to acquire a pre-measured characteristic impedance of a standard cable within the preset frequency range;

[0151] A second vector determining unit 405 determines a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0152] The weight loss quality determination unit 406 determines the weight loss quality of the conductor of the cable to be tested based on the peak vector of the cable to be tested and the peak vector of the standard cable, wherein the weight loss quality is used to determine whether the cross-sectional area of ​​the conductor of the cable to be tested is reduced.

[0153] Figure 5 A schematic diagram of a non-destructive determination device for the weight loss quality of a cable conductor provided in one or more embodiments of this specification includes:

[0154] at least one processor; and,

[0155] a memory communicatively connected to the at least one processor; wherein,

[0156] The memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0157] Within a preset frequency range, measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state;

[0158] Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part;

[0159] Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0160] Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range;

[0161] Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0162] The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

[0163] One or more embodiments of this specification provide a non-volatile computer storage medium storing computer executable instructions, which can achieve the following when executed by a computer:

[0164] Within a preset frequency range, respectively measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state;

[0165] Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part;

[0166] Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance;

[0167] Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range;

[0168] Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance;

[0169] The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

[0170] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device, equipment, and non-volatile computer storage medium embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0171] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0172] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0173] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, 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 through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0174] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0175] In addition, each functional unit in each embodiment of the present application 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. The above units may be implemented in the form of hardware or software.

[0176] If the integrated module / 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 present application implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electric carrier signals and telecommunication signals.

[0177] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such 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 application, and should all be included in the protection scope of the present application.

Claims

1. A non-destructive method for determining the weight loss quality of a cable conductor, characterized in that: include: Within a preset frequency range, measuring a first impedance spectrum when the end of the cable to be tested is in an open circuit state, and measuring a second impedance spectrum when the end of the cable to be tested is in a short circuit state; Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part; Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance; Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range; Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance; The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

2. The method according to claim 1, characterized in that: The obtaining the characteristic impedance of the cable to be inspected based on the first impedance spectrum and the second impedance spectrum includes: By formula The characteristic impedance of the cable to be tested is obtained, where Z0 is the characteristic impedance of the cable to be tested, and Z open For the first impedance spectrum, Z short is the second impedance spectrum.

3. The method according to claim 1, characterized in that: The determining, based on the imaginary part of the characteristic impedance, the characteristic peak frequency vector of the cable to be inspected and the peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector comprises: Based on the imaginary part of the characteristic impedance, determining a peak curve that varies with the test frequency within the preset frequency range; The characteristic peak frequency vector of the cable to be inspected and the peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector are determined in the peak vector curve.

4. The method according to claim 1, characterized in that The step of determining the weight loss quality of the conductor of the cable to be inspected based on the peak vector of the cable to be inspected and the peak vector of the standard cable includes: Determine a first root mean square value of the peak vector of the cable to be tested, and determine a second root mean square value of the peak vector of the standard cable; Based on the first root mean square value and the second root mean square value, the weight loss quality of the cable conductor to be inspected is determined.

5. The method according to claim 4, characterized in that Determining a first root mean square value of the peak vector of the cable to be tested, and determining a second root mean square value of the peak vector of the standard cable, comprises: By formula Determine a first root mean square value of the peak vector of the cable to be inspected, wherein rmsBy′ is the first root mean square value of the peak vector of the cable to be inspected, and b′(f(i)) is the peak vector of the cable to be inspected; By formula Determine a second root mean square value of the peak vector of the standard cable, wherein rmsBy is the second root mean square value of the peak vector of the standard cable, b(f(i)) is the peak vector of the standard cable, and n is a constant greater than 0.

6. The method according to claim 5, characterized in that The step of determining the weight loss quality of the cable conductor to be inspected based on the first root mean square value and the second root mean square value includes: Based on the ratio of the first root mean square value to the second root mean square value, the weight loss quality of the cable conductor to be inspected is determined.

7. The method according to claim 6, characterized in that The step of judging the weight loss quality of the cable conductor to be inspected based on the ratio of the first root mean square value to the second root mean square value includes: By judging the condition rmsBy′ / rmsBy≥K ， Performing weight loss quality judgment on the cable to be inspected, wherein K is a weight loss quality evaluation parameter set based on the preset frequency range; If rmsBy′ / rmsBy≥K, it is determined that the cable to be inspected has a thin quality.

8. A non-destructive determination device for the weight loss quality of a cable conductor, characterized in that: include: An impedance spectrum measuring unit, which measures a first impedance spectrum of the cable to be tested in an open circuit state and a second impedance spectrum of the cable to be tested in a short circuit state within a preset frequency range; A characteristic impedance determining unit, which obtains a characteristic impedance of the cable to be tested based on the first impedance spectrum and the second impedance spectrum, wherein the characteristic impedance includes a real part and an imaginary part; A first vector determination unit, which determines a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance; A characteristic impedance acquisition unit, which acquires the characteristic impedance of the standard cable within the preset frequency range measured in advance; A second vector determination unit, which determines the peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance; The slimming quality judging unit judges the slimming quality of the conductor of the cable to be tested based on the peak vector of the cable to be tested and the peak vector of the standard cable, wherein the slimming quality is used to determine whether the cross-sectional area of ​​the conductor of the cable to be tested is reduced.

9. A non-destructive determination device for the weight loss quality of cable conductors, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to: Within a preset frequency range, measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state; Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part; Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance; Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range; Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance; The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

10. A non-volatile computer storage medium, characterized in that: Computer executable instructions are stored, and when the computer executable instructions are executed by a computer, the following can be achieved: Within a preset frequency range, measuring a first impedance spectrum of the cable to be tested in an open circuit state, and measuring a second impedance spectrum of the cable to be tested in a short circuit state; Based on the first impedance spectrum and the second impedance spectrum, a characteristic impedance of the cable to be tested is obtained, where the characteristic impedance includes a real part and an imaginary part; Determining a characteristic peak frequency vector of the cable to be inspected and a peak vector of the cable to be inspected corresponding to the characteristic peak frequency vector based on the imaginary part of the characteristic impedance; Obtaining a pre-measured characteristic impedance of a standard cable within the preset frequency range; Determining a peak vector of the standard cable corresponding to the characteristic peak frequency vector based on the imaginary part of the standard characteristic impedance; The weight loss mass of the conductor of the cable to be inspected is determined based on the peak vector of the cable to be inspected and the peak vector of the standard cable. The weight loss mass is used to determine whether the cross-sectional area of ​​the conductor of the cable to be inspected is reduced.

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