A method for measuring and analyzing the crimping resistance of cable fittings

Abstract

The present invention relates to the technical field of electric power grid, and specifically to a cable fitting crimping resistance measurement and analysis method, comprising: S100, obtaining the position of the measured cable, connecting the measured cable to a measuring fixture, and determining the corresponding measuring point on the measured cable; S200, measuring the cable resistance according to the measuring point on the measured cable, and determining the measured resistance value of the corresponding measuring point at each measurement; based on the obtained measured resistance value, determining the resistance standard deviation between the measured resistance value corresponding to each measuring point and the preset resistance value as the first error; using the resistance standard deviation extracted from the historical data of each measuring point as the second error, and obtaining the uncertainty index of the corresponding measuring point according to the first error and the second error. High precision and high efficiency of resistance measurement are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of electric power grid, and in particular to a method for measuring and analyzing the crimping resistance of cable hardware. Background Art

[0002] Cable joints are an important part of cable lines, used to connect cable lengths and cross-connect three-phase lines. Whether the cable line can operate safely depends largely on the success of the cable core connection. There are two ways to connect the cable core: welding and crimping. Due to the high technical requirements of the welding process, crimping is currently commonly used to connect the cable core. The use of crimping to connect the conductor core changes the flow cross-section of the joint connection point. The contact resistance between the connecting tube and the crimping surface of the cable core (hereinafter referred to as crimping resistance) is the main reason for the heating of the cable intermediate joint. The larger the crimping resistance, the lower the current carrying capacity of the cable intermediate joint.

[0003] For example, Chinese patent publication No. CN105277794A discloses a method and system for measuring the crimping resistance of a cable connector. A first measuring point, a second measuring point and a third measuring point are respectively set at both ends of the cable connector and on the cable, a current is applied to the cable connector, and the temperature of the cable connector is detected. When the temperature of the cable connector reaches a steady state, the effective voltage, the effective current and the phase angle between the first measuring point and the third measuring point and between the second measuring point and the third measuring point are measured, and then the AC resistance between the first measuring point and the third measuring point and the AC resistance between the second measuring point and the third measuring point are calculated according to the AC resistance calculation formula, and the absolute value of the difference between the two AC resistances is calculated to obtain the crimping resistance of the cable connector.

[0004] However, when measuring resistance, if the current is unstable or other conditions occur, the calculated resistance is prone to fluctuations. When the calculated resistance value fluctuates greatly, the measurement accuracy will be reduced and the measured resistance will deviate. Summary of the invention

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A cable fitting crimping resistance measurement and analysis method, comprising:

[0007] S100, obtaining the position of the cable under test, connecting the cable under test to a measuring fixture, and determining a corresponding measuring point on the cable under test.

[0008] S200, measuring the cable resistance according to the measuring points on the measured cable, and determining the measured resistance value of the corresponding measuring point at each measurement; based on the obtained measured resistance value, determining the resistance standard deviation between the measured resistance value corresponding to each measuring point and the preset resistance value as the first error; taking the resistance standard deviation extracted from the historical data of each measuring point as the second error, and obtaining the uncertainty index of the corresponding measuring point according to the first error and the second error.

[0009] S300, based on the acquired uncertain indicators, extracting environmental parameters corresponding to the uncertain indicators, and determining the correlation between the environmental parameters and the uncertain indicators.

[0010] S400, based on the correlation between the environmental parameters and the uncertainty indicators, a corresponding value change curve is generated for the uncertainty indicators according to the measurement time and location, the change value of the uncertainty indicators when the value changes, and the currently set measurement point is adjusted according to the change value of the uncertainty indicators.

[0011] The beneficial effects of the present invention are as follows: 1. The present invention measures the cable resistance by obtaining the position of the measured cable, connecting the measuring fixture, and determining the measuring point, while considering the first error between the measured resistance value and the preset resistance value and the second error in the historical data, so as to more accurately evaluate the uncertainty and error of each measurement.

[0012] Second, the present invention extracts environmental parameters corresponding to uncertain indicators and analyzes the correlation between environmental parameters and uncertain indicators, which helps to understand the impact of different environmental factors on measurement results and provides a basis for subsequent adjustment of measurement points.

[0013] 3. The present invention dynamically adjusts the currently set measuring points according to the changing value of the uncertain index. Through priority setting and interpolation operation, the layout of the measuring points is optimized, so that measuring points are added in high-priority areas, which improves the pertinence and effectiveness of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0015] Figure 1 The invention is a flow chart of a cable fitting crimping resistance measurement and analysis method. DETAILED DESCRIPTION

[0016] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. If no specific techniques or conditions are specified in the embodiments, the techniques or conditions described in the literature in the art or the product specifications are used.

[0017] See also Figure 1, a cable fitting crimping resistance measurement and analysis method, comprising:

[0018] S100, obtaining the position of the measured cable, connecting the measured cable to the measuring fixture, and determining the corresponding measuring points on the measured cable; the positions of the measuring points include measuring the inner conductor of the cable, the insulation layer of the cable, the metal sheath of the cable, and other measuring points, which are used to determine the rate of change of the internal current of the cable when the current passes through, so as to identify the resistance caused by the corresponding skin effect when the current change rate changes, and the change in resistance value caused by the corresponding wire cross section, so as to identify the resistance of the cable when it is working.

[0019] S200, measuring the cable resistance according to the measuring points on the measured cable, and determining the measured resistance value of the corresponding measuring point at each measurement; based on the obtained measured resistance value, determining the resistance standard deviation between the measured resistance value corresponding to each measuring point and the preset resistance value as the first error; taking the resistance standard deviation extracted from the historical data of each measuring point as the second error, and obtaining the uncertainty index of the corresponding measuring point according to the first error and the second error.

[0020] The first error is used to indicate the error between the resistance value measured at the corresponding measuring point in a fixed measurement sequence and the preset value. The first error is also used to determine the uncertainty measure generated when measuring resistance. The uncertainty measure is used to indicate the degree of change in the resistance value measurement during resistance measurement. The second error is determined by the resistance error measured for this type of measurement point with the same settings in history, to determine the value of the measured resistance difference during the current measurement. The uncertainty index obtained at this time is used to express the range value in which the measured resistance value mainly fluctuates during the corresponding calculation. This uncertainty index is mainly used to determine whether the resistance measured during the current calculation is stable. If the currently selected measurement point is unstable, the position of the corresponding measurement point is adjusted so that the crimping resistance obtained during the final measurement is accurate and reliable.

[0021] S300, based on the acquired first error and second error, extract a first error point corresponding to the first error and a second error point corresponding to the second error, and adjust the uncertainty indicator based on the first error point and the second error point.

[0022] S400, based on the adjusted uncertainty indicator, extracting the environmental parameter corresponding to the uncertainty indicator, and determining the correlation between the environmental parameter and the uncertainty indicator.

[0023] Environmental parameters include the measurement current used during measurement, the parameters corresponding to each measurement point, the conductor cross-section, insulation layer, conductor thickness, metal sheath, etc. The correlation between the environmental parameters and uncertainty indicators measured at these locations, based on the differences in the values ​​of these measured environmental parameters, and whether the uncertainty indicators obtained by measurement calculation have changed accordingly;

[0024] S500, based on the correlation between the environmental parameters and the uncertain indicators, a corresponding value change curve is generated for the uncertain indicators according to the measurement time and location, and the probability and location of the uncertain indicators when the value changes; according to the probability and location of the uncertain indicators, the currently set measurement points are adjusted.

[0025] The methods for obtaining the measured resistance value include:

[0026] First, determine the standard resistance value at the corresponding measuring point per unit length during measurement. Among them, R DC is the standard resistance value of the measuring point per unit length, ρ is the resistivity of the material corresponding to the measuring point, S is the cross-sectional area at the corresponding position of the measuring point, and according to the obtained standard resistance value; determine the change in the contact area during crimping at this time. This contact area is used to determine that the contact area between metal parts will increase or decrease due to deformation during the cable crimping process. According to the obtained standard resistance value, calculate the equivalent cross-sectional area of ​​the cable conductor at each measuring point; Where ρ is the resistivity of the material at the measurement point, R c is the standard resistance value when crimped, L is the length of the cable conductor, and S1 is the equivalent cross-sectional area.

[0027] According to the calculated equivalent cross-sectional area, the change value of the corresponding area during crimping is determined, and the inverse relationship between the equivalent cross-sectional area and the resistance between the metal parts during crimping is judged. If the currently calculated standard resistance value and the equivalent cross-sectional area value match, the corresponding standard resistance value is used as the measured resistance value of the measuring point. If the currently calculated resistance value and the equivalent cross-sectional area value do not match, the resistance value of the standard resistance value after the temperature change is used as the measured resistance value corresponding to the measuring point. At this time, the product of the resistivity of the corresponding material and the length of the cable conductor is determined to be the same as the product of the currently calculated resistance value and the equivalent cross-sectional area value. If they are the same, it means that the calculated resistance value and the equivalent cross-sectional area value match. If they are different, it means that the resistance value is affected by the temperature change, resulting in an increase in the resistance value. Then, the change amplitude of the resistance value of the cable when the temperature changes is obtained to determine the resistance value after the temperature change; if the currently calculated resistance value and the equivalent cross-sectional area value match, the corresponding temperature, equivalent cross-sectional area, resistance value and measuring point position are recorded.

[0028] The way to determine the resistance value after temperature change is:

[0029] Among them, R t is the resistance value after temperature change, R′ is the standard resistance value at the current temperature, δ is the temperature conversion coefficient, and t is the current cable temperature.

[0030] The temperature conversion coefficient will be adjusted according to the current cable material, such as 0.00374 for copper, 0.00383 for aluminum, or other similar values, to determine the change in resistance when the temperature changes. At the same time, this value is compared with the directly measured value to determine the range of resistance change.

[0031] According to the change in the resistance in the cable, record the resistance values ​​measured under different conditions, and also record the value range of these resistance values ​​measured under the same measurement conditions when measured and compared multiple times.

[0032] The measured resistance values ​​are compared with the preset resistance to determine the probability interval of resistance value change during the comparison, and the first error and the second error corresponding to the resistance standard deviation are obtained according to the probability interval of resistance value change.

[0033] At this time, the standard deviation of the resistance is determined by averaging the multiple resistance values ​​measured above to determine the corresponding error during measurement, which is used to evaluate the dispersion of the resistance value and the deviation from the preset value.

[0034] The first error obtained can be expressed as:

[0035] Among them, σ1 is the first error, R i is the measured resistance value of the i-th measurement point, R0 is the preset resistance value, n is the number of measurement points, i = 1, 2,,, n. The second error is obtained in the same manner as the first error, and the obtained second error includes the corresponding measurement point where the error occurs and the corresponding time.

[0036] At this time, the method for obtaining the uncertain indicator in step S200 is:

[0037]

[0038] Among them, γ is the uncertainty index, σ1 is the first error, σ2 is the second error, w1 is the weight of the first error, and w2 is the weight of the second error. The uncertainty index obtained at this time can reduce the possible range of resistance during measurement and improve the accuracy of resistance measurement.

[0039] At the same time, when obtaining the uncertainty index, the uncertainty index obtained can also be adjusted by adjusting the measurement points selected when calculating the first error and the second error. The first error point and the second error point corresponding to the first error and the second error are extracted, and the first error point is compared with the second error point to obtain the corresponding uncertainty index.

[0040] Then, after obtaining the first error, the method of extracting the first error point corresponding to the first error and the second error point corresponding to the second error is:

[0041] According to the measurement sequence selected during measurement, the measurement points at which the error value between the measured resistance value and the preset resistance value is greater than the first error are extracted and marked as the first error points. The first error points are marked according to the position and time during measurement, and it is determined whether there is a measurement point identical to the first error point among the measurement points corresponding to the second error. At this time, the corresponding point is determined according to the position of the measurement point during cable measurement, and the error value between the measured resistance value of the measurement point at this position and the preset resistance value is checked. If the measurement point corresponding to the second error has the same position as the first error point and the error value between the measured resistance value of the corresponding measurement point and the preset resistance value is consistent, the corresponding first error point is extracted as the second error point. If they are not consistent, the point is not extracted as the second error point. The second error point represents the intersection of the corresponding measurement points when the first error and the second error are measured, and is used to determine the point that satisfies the error of historical data and the current measurement error. At this time, calculation of these measurement points can facilitate the determination of the error generated during the overall measurement.

[0042] The above measurement sequence indicates that the resistance values ​​related to the measurement points are obtained in a certain order and position. The measurement sequence is mainly used to process the measurement points in sequence according to the corresponding time sequence to obtain the measurement points in each corresponding time period, so as to facilitate the judgment of whether the resistance value measured in the current time period is the resistance value during normal operation.

[0043] In step S300, the uncertainty index is adjusted based on the first error point and the second error point as follows:

[0044] γ=w3×log2(1+σ3)+w4×log2(1+σ4);

[0045] Among them, γ is the uncertainty index of adjustment, σ3 is the resistance standard deviation of the measured resistance value corresponding to the first error point, σ4 is the resistance standard deviation of the measured resistance value corresponding to the second error point, w3 is the weight of the first error point, and w4 is the weight of the second error point.

[0046] Using the first error and the second error to directly calculate the uncertainty index is a relatively macro method, which takes into account the overall error situation of all measurement points; while extracting the first error point and the second error point to obtain the uncertainty index is a more detailed method; it focuses on which specific measurement points have produced large errors, and the consistency of these error points in historical data and current measurements; by comparing the first error point and the second error point, it can be determined whether the current measurement is consistent with the historical data, and the uncertainty index currently obtained can be adjusted according to the value of this comparison.

[0047] After the uncertainty index is obtained, a measurement point where the uncertainty index is less than a set index value during two measurements is selected, and the corresponding crimping resistance during crimping is determined according to the difference between the two measurement points.

[0048] When determining the correlation between environmental parameters and uncertainty indicators, it also includes determining the temperature corresponding to the uncertainty indicator based on the calculated uncertainty indicator, and determining the difference between the temperature and the uncertainty indicator; for example, obtaining the temperature value corresponding to the measured uncertainty indicator, determining the range of the measured uncertainty indicator under constant temperature conditions, and comparing the difference between the corresponding uncertainty indicators at each measured temperature, and using this part of the difference that changes with temperature as the difference between the identified temperature and the uncertainty indicator.

[0049] Then, the correlation between the environmental parameters and the uncertainty index determined in step S400 can be expressed as:

[0050]

[0051] Among them, r is the correlation between environmental parameters and uncertainty indicators, x j is the value of the jth environmental parameter, γ j is the value of the uncertainty index corresponding to the jth environmental parameter, is the mean value of the environmental parameter, is the mean of the uncertainty index, m is the number of environmental parameters, j = 1, 2,,,m.

[0052] At this time, by determining the value of the corresponding uncertain indicator under different environmental parameters, it is determined which environmental parameters the uncertain indicator is susceptible to.

[0053] The possible influence of the corresponding environmental parameters on the uncertain indicators is determined according to the correlation between the obtained uncertain indicators and the environmental parameters, so as to screen out the environmental parameters corresponding to the abnormal points when the abnormal points appear in the time series, and the instability in the resistance measurement can be prevented by identifying the environmental parameters.

[0054] At the same time, regression analysis can be used to determine the relevance of each environmental parameter to the uncertain index. The regression analysis method is to compare the data calculated by adding the scores of all environmental parameters and weights plus the initial terms with the uncertain index, so as to continuously iterate the weight corresponding to each environmental parameter, so as to identify whether the corresponding environmental parameter can affect the measurement of the current resistance.

[0055] The processing method of the value change curve in step S500 includes generating a time series according to the time of the uncertain indicator, creating a spatial distribution map in combination with the position of the uncertain indicator, and determining the probability and position of the occurrence of the uncertain indicator.

[0056] For the acquired time series, identify the changing trend in the time series, determine the changing trend of the uncertain indicators in the corresponding time period, distribute the probability of the uncertain indicators in the corresponding time series, and determine the probability of the uncertain indicators appearing in the corresponding time period based on the obtained probability distribution.

[0057] The probability of the occurrence of uncertain indicators is expressed as:

[0058]

[0059] Among them, P is the probability of occurrence of the uncertain indicator, γ′ is the standard deviation of the uncertain indicator, γ″ is the mean of the uncertain indicator, π is the circumference of a circle, and e is the exponential constant.

[0060] The identified change trend indicates the increase or decrease in the value of the uncertain indicator in a specific time period or a fixed time period, and determines the probability of occurrence of the uncertain indicator under these corresponding trends. Based on the obtained probability of occurrence, the change of the uncertain indicator over time is determined.

[0061] For the differences between uncertainty indicators at different locations, the indicator differences between the uncertainty indicators of the measuring points at different locations within a fixed time period and the target values ​​are displayed, and the corresponding uncertainty indicators are sorted according to the size of the indicator differences.

[0062] Based on the probability and location of the uncertain indicators, the methods for adjusting the currently set measurement points include:

[0063] Determine the indicator difference between the uncertainty indicator and the target value of the measuring points at different positions, process them according to the occurrence probability of the measuring points and the size of the indicator difference, set the measuring points with an occurrence probability greater than the preset occurrence probability and an indicator difference greater than the preset indicator value as the first priority points, and set the measuring points with an occurrence probability less than the preset occurrence probability and an indicator difference less than the preset indicator value as the second priority points.

[0064] The target value is determined by realizing the set value. The set value is the minimum value at which the error of the currently measured resistance value occurs, that is, the minimum fluctuation value allowed when measuring the resistance, to determine the position at which a higher difference is likely to occur during measurement.

[0065] For the first priority point, the occurrence probability corresponding to the first priority point is marked, and the measurement point closest to the first priority point is determined for each measurement. The measurement point obtained at this time represents the position of the measurement point closest to the first priority point on the cable when performing resistance value measurement calculation. Interpolation operation is performed on the measurement point closest to the first priority point to determine the uncertainty index value of the first priority point after the interpolation operation, and the uncertainty index value of the first priority point after the interpolation operation is used as the uncertainty index value of the adjusted first priority point.

[0066] For the interpolation operation, the first priority point for linear interpolation is selected by selecting two measurement points closest to the first priority point:

[0067]

[0068] Among them, b p is the coordinate value corresponding to the position of the first priority point, a p is the uncertainty index value of the first priority point, b0 and b1 are the coordinate values ​​corresponding to the positions of the two measurement points closest to the first priority point, a0 and a1 are the uncertainty index values ​​of the two measurement points closest to the first priority point, a0<a1, b0<b1.

[0069] When performing the interpolation operation on the first priority point as mentioned above, if the position of the first priority point is adjusted, the coordinate value corresponding to the position of the first priority point is adjusted based on the uncertainty index value of the first priority point, that is, the uncertainty index of the first priority point is substituted into the above formula, and the position after interpolation is calculated to determine the coordinate value of the first priority point; if the uncertainty index of the first priority point is adjusted, the corresponding uncertainty index value of the first priority point is calculated based on the coordinate value corresponding to the position of the first priority point.

[0070] For the second priority point, adjust the second priority point according to the position where it appears, determine that each second priority point has at least one corresponding first priority point in the adjacent area, and use the area set at this time as the area corresponding to the second priority point for measurement.

[0071] At the same time, based on the above adjustment method, according to the correlation between environmental parameters and uncertainty indicators, and the differences between uncertainty indicators at different positions, the target areas are extracted. These target areas are obtained by extracting the measurement points corresponding to the first ten percent of the data in the sorting of uncertainty indicators, and according to the correlation between environmental parameters and uncertainty indicators, the measurement points whose slope of the change trend in the time series is greater than the preset part are extracted to determine the measurement points at the corresponding positions. According to the measurement points extracted at these positions, the current situation is analyzed to evaluate the main influencing factors of the target area; and according to the identified influencing factors, the distribution and position of the measurement points are adjusted in time to improve the measurement efficiency.

[0072] Initialize an empty collection to store the adjusted measurement points.

[0073] Traverse the current set of measurement points.

[0074] For each measurement point, a flag is initialized to indicate whether the point needs to be adjusted.

[0075] Traverse the set of identified influencing factors.

[0076] If the current measurement point is significantly affected by a certain influencing factor, the position or distribution of the measurement point is adjusted according to the influencing factor, and the adjusted measurement point is added to the adjusted set, and the adjustment flag is set to true.

[0077] If a measured point is not significantly affected by any influencing factor, its original position is retained and it is added to the adjusted set.

[0078] Returns the adjusted set of measurement points.

[0079] According to the adjusted measurement point set, the obtained resistance value is output to determine the current measured resistance value. At this time, the adjusted measurement point is mainly based on the uncertainty index obtained after adjusting the first priority point and the second priority point, and the corresponding resistance value of this part of the measurement points is output.

[0080] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations on the present invention. A person skilled in the art may make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention and they are still covered by the protection scope of the present invention.

Claims

1. A cable fitting crimping resistance measurement and analysis method, characterized in that: include: S100, obtaining the position of the cable under test, connecting the cable under test to a measuring fixture, and determining a corresponding measuring point on the cable under test; S200, measuring the cable resistance according to the measuring points on the measured cable, and determining the measured resistance value of the corresponding measuring point in each measurement; based on the obtained measured resistance value, determining the resistance standard deviation between the measured resistance value corresponding to each measuring point and the preset resistance value as the first error; The standard deviation of the resistance extracted from the historical data of each measuring point is used as the second error, and the uncertainty index of the corresponding measuring point is obtained according to the first error and the second error; In step S200, the method for obtaining the uncertain indicator is: Among them, γ is the uncertainty index, σ1 is the first error, σ2 is the second error, w1 is the weight of the first error, and w2 is the weight of the second error; S300, based on the acquired first error and second error, extracting a first error point corresponding to the first error and a second error point corresponding to the second error, and adjusting the uncertainty indicator based on the first error point and the second error point; In step S300, the uncertainty index is adjusted based on the first error point and the second error point obtained as follows: γ=w3×log2(1+σ3)+w4×log2(1+σ4); Wherein, γ is the adjusted uncertainty index, σ3 is the resistance standard deviation of the measured resistance value corresponding to the first error point, σ4 is the resistance standard deviation of the measured resistance value corresponding to the second error point, w3 is the weight of the first error point, and w4 is the weight of the second error point; S400, based on the adjusted uncertain index, extracting the environmental parameter corresponding to the uncertain index, and determining the correlation between the environmental parameter and the uncertain index; The correlation between the environmental parameters and the uncertainty index determined in step S400 is expressed as: Among them, r is the correlation between environmental parameters and uncertainty indicators, x j is the value of the jth environmental parameter, γ j is the value of the uncertainty index corresponding to the jth environmental parameter, is the mean value of the environmental parameter, is the mean value of the uncertainty index, m is the number of environmental parameters, j = 1, 2, ..., m; S500, based on the correlation between the environmental parameters and the uncertain indicators, generating a corresponding value change curve for the uncertain indicators according to the measurement time and location, determining the probability and location of the uncertain indicators when the value changes; and adjusting the currently set measurement point according to the probability and location of the uncertain indicators; The processing method of the numerical change curve includes generating a time series according to the time of the uncertain indicator, and creating a spatial distribution map in combination with the position of the uncertain indicator to determine the probability and position of the occurrence of the uncertain indicator; The probability of the occurrence of uncertain indicators is expressed as: Among them, P is the probability of occurrence of the uncertain indicator, γ′ is the standard deviation of the uncertain indicator, γ″ is the mean of the uncertain indicator, π is the circumference of a circle, and e is the exponential constant.

2. A cable fitting crimping resistance measurement and analysis method according to claim 1, characterized in that: The methods for obtaining the measured resistance value include: First, determine the standard resistance value at the corresponding measuring point per unit length during measurement, and calculate the equivalent cross-sectional area of ​​the cable conductor at each measuring point based on the obtained standard resistance value; based on the calculated equivalent cross-sectional area, determine the inverse relationship between the equivalent cross-sectional area and the resistance between metal parts during the crimping process. If the currently calculated standard resistance value and the equivalent cross-sectional area value match, use the corresponding standard resistance value as the measured resistance value of the measuring point; if the currently calculated resistance value and the equivalent cross-sectional area value do not match, use the resistance value of the standard resistance after the temperature change as the measured resistance value corresponding to the measuring point.

3. A cable fitting crimping resistance measurement and analysis method according to claim 1, characterized in that: The first error obtained can be expressed as: Among them, σ1 is the first error, R i is the measured resistance value of the i-th measuring point, R0 is the preset resistance value, n is the number of measuring points, i=1,2,......,n.

4. A cable fitting crimping resistance measurement and analysis method according to claim 1, characterized in that: The method of extracting the first error point corresponding to the first error and the second error point corresponding to the second error is: According to the measurement sequence selected during measurement, the measurement points at which the error value between the measured resistance value and the preset resistance value is greater than the first error are extracted and marked as the first error points. The first error points are marked according to the position and time during measurement, and it is determined whether there is a measurement point identical to the first error point among the measurement points corresponding to the second error. If the measurement point corresponding to the second error has the same position as the first error point and the measured resistance value of the corresponding measurement point is consistent with the error value of the preset resistance value, the corresponding first error point is extracted as the second error point. If they are not consistent, the measurement point is not extracted as the second error point.

5. A cable fitting crimping resistance measurement and analysis method according to claim 1, characterized in that: The method of adjusting the currently set measurement point based on the probability and location of the occurrence of the uncertain indicator includes: Determine the index difference between the uncertainty index and the target value of the measuring points at different positions, process them according to the occurrence probability of the measuring points and the size of the index difference, set the measuring points with an occurrence probability greater than the preset occurrence probability and an index difference greater than the preset index value as the first priority point, and set the measuring points with an occurrence probability less than the preset occurrence probability and an index difference less than the preset index value as the second priority point; For the first priority point, the occurrence probability corresponding to the first priority point is marked, and the measurement point closest to the first priority point is determined for each measurement. The measurement point obtained at this time represents the position of the measurement point closest to the first priority point on the cable when performing resistance value measurement calculation. Interpolation operation is performed on the measurement point closest to the first priority point to determine the uncertainty index value of the first priority point after the interpolation operation, and the uncertainty index value of the first priority point after the interpolation operation is used as the uncertainty index value of the first priority point after the adjustment; For the second priority point, adjust the second priority point according to the position where it appears, determine that each second priority point has at least one corresponding first priority point in the adjacent area, and use the area set at this time as the area corresponding to the second priority point for measurement.

6. A cable fitting crimping resistance measurement and analysis method according to claim 5, characterized in that: For the interpolation operation, the first priority point for linear interpolation is selected by selecting two measurement points closest to the first priority point: Among them, b p is the coordinate value corresponding to the position of the first priority point, a p is the uncertainty index value of the first priority point, b0 and b1 are the coordinate values ​​corresponding to the positions of the two measurement points closest to the first priority point, a0 and a1 are the uncertainty index values ​​of the two measurement points closest to the first priority point, a0<a1, b0<b1.

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