Synchronous detection method for abrasion and geometric irregularity of rigid contact network

Abstract

The invention discloses a synchronous detection method for abrasion and geometric irregularity of a rigid contact network, which comprises the following steps of: arranging N high-precision displacement sensors at equal intervals along the transverse direction of the contact network on a rigid carrier bridged above the contact network to form a space detection array; driving the rigid carrier to move along the extension direction of the overhead line system, and synchronously collecting real-time distance measurement values of all the sensors at continuous spatial positions; based on the independent historical reference data of each sensor, the abrasion loss of the contact line at the corresponding position of each sensor is obtained; based on the spatial distance relation of the N sensors at the same sampling moment, the geometric irregularity of the contact line on the section is obtained. According to the method, the innovative thought of one chord and N points is adopted, through the high-precision displacement sensor array and the synchronous acquisition technology, the accuracy and relevance of detection data are guaranteed, the detection precision is improved, synchronous detection of abrasion and geometric irregularity is achieved, the detection efficiency is improved, and the detection time and cost are reduced.

Description

Technical Field

[0001] This invention relates to the field of contact wire condition detection technology, specifically to a method for simultaneous detection of wear and geometric irregularities in rigid contact wires. Background Technology

[0002] Rigid contact networks are widely used in urban rail transit, high-speed railways, and heavy-haul railways, and are an important component of the electric locomotive power collection system. With the increase in train speed and frequency, the contact network system faces serious mechanical wear and geometric irregularities, which in turn affect the reliability of power supply and the safety of train operation. Existing detection technologies mainly include the following categories: (1) single-point laser or visual measurement, which has limited spatial information; (2) line-scan three-dimensional modeling, which is costly and has complex data processing; (3) mobile platform detection, which is difficult to balance high precision and portability.

[0003] These methods generally suffer from problems such as limited detection point coverage, inability to restore continuous spatial morphology, weak ability to identify local anomalies, and insufficient ability to identify high-precision wear and small-scale geometric disturbances.

[0004] Therefore, there is an urgent need to propose a method for high-density, multi-point spatial detection of rigid contact wires without increasing system complexity, especially for simultaneously identifying wear and unevenness features. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a method for the simultaneous detection of wear and geometric irregularities in rigid contact wires.

[0006] The technical solution of this invention to solve the above-mentioned technical problems is as follows: A method for synchronously detecting wear and geometric irregularities of rigid contact wires provided by this invention includes the following steps: S1: On a rigid carrier spanning above the contact wire, N high-precision displacement sensors are arranged at equal intervals along the transverse direction of the contact wire to form a spatial detection array; S2: Drive the rigid carrier to move along the extension direction of the contact wire, and simultaneously collect the real-time distance measurement values ​​of all sensors at continuous spatial positions; S3: Based on the independent historical reference data of each sensor, obtain the wear amount of the contact wire at the corresponding position of each sensor; S4: Based on the spatial distance relationship of N sensors at the same sampling time, obtain the geometric irregularity of the contact wire at this cross section.

[0007] Furthermore, wear parameters are generated by comparing the current measurement value of a single sensor with its historical baseline data; The geometric irregularity parameter is generated by the spatial relative relationship of the distance values ​​of N sensors at the same time.

[0008] Furthermore, step S3 includes the following steps: S3.1: Establish a dynamic benchmark mapping relationship for each detection point, which is associated with historical benchmark values ​​and environmental parameters; S3.2: Obtain the current environmental parameters in real time and generate a compensated benchmark value based on the dynamic benchmark mapping relationship; S3.3: Calculate the difference between the current measured value and the compensated reference value, and use it as the wear depth at a single point; S3.4: Perform spatial continuity analysis on multiple consecutive single-point wear depths along the extension direction and output wear parameters.

[0009] Furthermore, the establishment of the dynamic reference mapping relationship in step S3.1 includes: first, calibrating the initial reference value of each detection point under the standard contact network condition, then determining the environmental compensation coefficient through temperature and humidity experiments, and constructing a functional model of the reference value and environmental parameters.

[0010] Furthermore, step S4 includes the following steps: S4.1: Divide N detection points of the same spatial section into M overlapping analysis units, each unit containing at least three detection points in continuous spatial locations; S4.2: Calculate the geometric deviation representing the local deformation of the contact line for each element; S4.3: Aggregate the geometric deviations of all units to generate a cross-sectional irregularity index.

[0011] Furthermore, the calculation method for the geometric deviation satisfies: For locations For the analysis unit, the geometric deviation G is defined by the following functional relationship: in, These are the measured values ​​at the corresponding locations.

[0012] Furthermore, step S4 also includes performing spatial straight line fitting on N measurements of the same cross section, calculating the vertical residual from each measurement point to the fitted straight line, and finally using the statistical characteristics of the residual as an index of the overall smoothness of the cross section.

[0013] Furthermore, the statistical characteristics include: Local irregularity amplitude: The maximum value of geometric deviation within the sliding analysis window; Continuous unevenness strength: Using a preset length as the evaluation unit, calculate the root mean square value of the vertical residual.

[0014] The present invention has the following beneficial effects: The present invention provides a method for simultaneous detection of wear and geometric irregularities in rigid contact wires: (1) This method enables simultaneous detection of wear and geometric irregularities, improving detection efficiency and reducing detection time and cost; (2) This method adopts the innovative idea of ​​"one string and N points". Through high-precision displacement sensor array and synchronous acquisition technology, it ensures the accuracy and correlation of detection data and improves detection accuracy.

[0015] (3) The establishment of dynamic benchmark mapping relationship in this method takes into account the influence of environmental factors on the test results, which improves the accuracy of wear calculation.

[0016] (4) The method of calculating geometric irregularity in this method can effectively characterize the local deformation and overall smoothness of the contact wire, providing a comprehensive evaluation basis for the maintenance and repair of the contact network. Attached Figure Description

[0017] Figure 1 This is the flowchart of the detection method of the present invention; Figure 2 This is a flowchart of the method for obtaining the wear amount of contact wire in this invention; Figure 3 This is a flowchart of the method for obtaining the contact wire unevenness in this invention. Detailed Implementation

[0018] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0019] like Figures 1 to 3 As shown, a method for simultaneously detecting wear and geometric irregularities in rigid contact wires includes the following steps: S1: On a rigid carrier spanning above the contact wire, N high-precision displacement sensors are arranged at equal intervals along the transverse direction of the contact wire to form a spatial detection array. The spacing between the sensors is determined according to the geometric characteristics of the contact wire and the detection accuracy requirements, and is generally 10-30cm.

[0020] Specifically, depending on the type of overhead contact line and the inspection environment, a carrier with sufficient strength and rigidity should be selected, such as a specially designed inspection trolley or an inspection device installed on a rail vehicle, to ensure that it can move stably above the overhead contact line and that its own deformation will not affect the inspection accuracy.

[0021] On a selected rigid carrier, N high-precision displacement sensors are arranged at equal intervals along the transverse direction of the contact wire (i.e., perpendicular to the extension direction of the contact wire). The spacing between the sensors should be determined based on the geometric parameters of the contact wire and the required detection accuracy, generally around 10-30 cm, to ensure detailed detection of the contact wire's geometric state. Simultaneously, it is crucial to ensure the sensors are accurately positioned and securely fixed to avoid measurement errors caused by sensor loosening or displacement during the detection process.

[0022] Connect each displacement sensor to the data acquisition system to ensure stable and reliable signal transmission. Before starting the formal testing, calibrate the sensors to eliminate their own errors and deviations, ensuring the accuracy of the measurement data. Calibration can be performed using a calibration device with a known standard distance, calibrating each sensor individually to match the sensor's measurement values ​​with the actual standard distance.

[0023] After completing the above steps, a spatial detection array is formed, evenly spaced along the transverse direction of the contact wire. This array can simultaneously acquire distance measurements at multiple points on the transverse cross-section of the contact wire, providing rich data support for subsequent wear and geometric irregularity analysis.

[0024] The simultaneous operation of multiple sensors in this spatial detection array allows for the acquisition of data from multiple points across the transverse cross-section of the overhead contact line. These data are interconnected and collectively describe the geometric state of the contact line at that cross-section. By analyzing the spatial relationships of this data, simultaneous detection of contact line wear and geometric irregularities can be achieved. This means acquiring two key pieces of contact line status information simultaneously in a single inspection, improving detection efficiency and data correlation.

[0025] S2: Drive the rigid carrier to move along the extension direction of the contact wire, simultaneously collecting real-time distance measurements from all sensors at continuous spatial positions. The moving speed can be adjusted according to detection efficiency and accuracy requirements, generally 0.1-0.5 m / s. Wear parameters are generated by comparing the current measurement value of a single sensor with its historical reference data. By analyzing the spatial relationship of these data, information on the wear and geometric irregularities of the contact wire can be obtained. For example, by comparing the real-time measurement value of each sensor with historical reference data, the wear amount of the contact wire can be calculated; by analyzing the spatial relative relationship of the measurement values ​​of multiple sensors within the same cross-section, the degree of geometric irregularity of the contact wire can be assessed.

[0026] S3: Based on the independent historical reference data of each sensor, obtain the wear amount of the contact wire at the corresponding position of each sensor, specifically including: S3.1: Establish a dynamic benchmark mapping relationship for each detection point, which is associated with historical benchmark values ​​and environmental parameters; The establishment of the dynamic reference mapping relationship in step S3.1 includes: first, calibrating the initial reference value of each detection point under the standard contact network condition, then determining the environmental compensation coefficient through temperature and humidity experiments, and constructing a functional model of the reference value and environmental parameters.

[0027] The dynamic baseline mapping relationship is as follows: Reference value = Initial calibration value + Temperature compensation coefficient × Temperature change + Humidity compensation coefficient × Humidity change; S3.2: Real-time acquisition of current environmental parameters, such as temperature and humidity, and generation of compensated reference values ​​based on the dynamic reference mapping relationship; S3.3: Calculate the difference between the current measured value and the compensated reference value as the single-point wear depth, i.e., wear depth = reference value - current measured value; S3.4: Perform spatial continuity analysis on multiple consecutive single-point wear depths along the extension direction and output wear parameters.

[0028] In this embodiment, the determination of the environmental compensation coefficient includes the following steps: (1) Set a series of different temperature and humidity combinations for environmental conditions that cover the range of working environments that the overhead contact line may actually encounter. For example, the temperature can be set from -20℃ to +50℃, with a temperature point set every 5℃ or 10℃; the humidity can be set from 30% RH to 90% RH, with a humidity point set every 10% RH. (2) Under each stable temperature and humidity environment, drive the rigid carrier to move along the contact wire, and synchronously collect the real-time distance measurement values ​​of all sensors. Repeat the measurement process multiple times and record the measurement data and the corresponding temperature and humidity values. (3) Organize the large amount of data collected and classify the measurement data according to different temperature and humidity conditions. For each detection point, calculate the difference between the measured value and the initial reference value under different temperature and humidity conditions. This difference is mainly due to the displacement change caused by the change in the geometric size of the contact network (such as thermal expansion and contraction) caused by environmental changes. (4) Using mathematical modeling methods such as multiple linear regression and neural networks, temperature and humidity are used as independent variables and the difference between the measured value and the initial baseline value is used as the dependent variable to establish a functional model between the baseline value and environmental parameters (temperature and humidity). For example, the model may be in the form of Δd = a×T + b ×H + c, where Δd is the difference between the measured value and the initial baseline value, T is temperature, H is humidity, and a, b, and c are undetermined coefficients.

[0029] The model was fitted and trained using a large amount of collected experimental data. Optimization algorithms, such as the least squares method, were used to determine the parameters a, b, and c in the model, thus obtaining a quantitative relationship between the environmental compensation coefficient and temperature and humidity. These coefficients constitute the environmental compensation coefficient, which is used to compensate for the baseline value based on real-time environmental parameters during actual testing, thereby improving the accuracy of wear calculation.

[0030] S4: Based on the spatial distance relationship of N sensors at the same sampling time, obtain the geometric irregularity of the contact wire at this cross section. The geometric irregularity parameter is generated by the spatial relative relationship of the distance values ​​of N sensors at the same time.

[0031] Specifically, the following steps are included: S4.1: Divide N detection points of the same spatial section into M overlapping analysis units, each unit containing at least three detection points in continuous spatial locations; By dividing the N detection points of the same spatial cross section into analysis units, a detailed local geometric deviation analysis of the contact network can be performed, thereby accurately obtaining the deformation of the contact network in various local areas and realizing a refined evaluation of the geometric state of the contact network. The overlapping setting is to avoid detection blind spots between units and ensure that the geometric state of the entire cross section can be fully evaluated.

[0032] S4.2: Calculate the geometric deviation representing the local deformation of the contact line for each element; The calculation method for the geometric deviation satisfies: For locations For the analysis unit, the geometric deviation G is defined by the following functional relationship: in, These are the measured values ​​at the corresponding locations.

[0033] The geometric deviation is calculated based on the measured values ​​of each detection point within the unit using the specific functional relationship described above. It reflects the degree of deviation between the local geometry of the contact line within the unit and the ideal state, and can indicate the unevenness of the contact line in that local area.

[0034] S4.3: Aggregate the geometric deviations of all units to generate a cross-sectional irregularity index.

[0035] By comprehensively processing the geometric deviations of each unit, such as by calculating the average value, maximum value, or other statistical methods, an index that can characterize the overall cross-sectional irregularity is obtained. This index can reflect the overall smoothness status of the catenary cross-section, providing crucial data support for catenary maintenance decisions.

[0036] Step S4 also includes performing spatial straight line fitting on N measurements of the same cross section, calculating the vertical residual from each measurement point to the fitted straight line, and finally using the statistical characteristics of the residual as the overall smoothness index of the cross section.

[0037] Specifically, spatial linear fitting: Spatial line fitting is performed on N measurements of the same cross section to find a straight line that best represents the trend of the contact network within that section. This straight line is obtained through mathematical calculations of the coordinate data of multiple measurement points, minimizing the vertical distance from all measurement points to this line in a statistical sense (such as the least squares method). For example, suppose there are 5 measurement points on a certain cross section with coordinates (x1, y1), (x2, y2), (x3, y3), (x4, y4), and (x5, y5). Through the spatial line fitting algorithm, a straight line y = ax + b can be determined, minimizing the sum (or sum of squares) of the vertical distances from these 5 points to this line, thus obtaining an overall trend line of the contact network at that cross section.

[0038] Vertical residual calculation: After obtaining the fitted straight line, the vertical residual from each measurement point to the fitted straight line is calculated. The vertical residual refers to the perpendicular distance from each measurement point to the fitted straight line, reflecting the degree of deviation of that measurement point relative to the fitted straight line. Taking the previous example, for the first measurement point (x1, y1), its vertical residual to the fitted straight line y=ax+b is |y1-(ax1+b)|. The larger this value, the greater the deviation of the contact wire geometry at that measurement point from the overall trend line, and the more likely there are local irregularities.

[0039] Statistical characteristics as smoothness indicators: Statistical characteristics include local irregularity amplitude and continuous irregularity intensity. Local irregularity amplitude is the maximum value of geometric deviation within a sliding analysis window. That is, a sliding window of a certain length is set along the extension direction of the contact wire (e.g., the window length could be 0.5 meters, 1 meter, etc., determined according to specific testing requirements). The maximum value of geometric deviation within this window is taken as the local irregularity amplitude. This indicator is mainly used to assess the degree of irregularity of the contact wire within a small area. For example, if within a 0.5-meter-long window, the geometric deviation at a certain location reaches 3 millimeters, while other locations are relatively smaller, then this 3 millimeters is the local irregularity amplitude, indicating a relatively significant irregularity in this local area, possibly caused by local damage, deformation, or installation errors in the contact wire.

[0040] The continuous irregularity strength is calculated by taking the root mean square (RMS) value of the vertical residuals using a preset length as the evaluation unit. For example, the preset length could be 10 meters, 20 meters, etc., dividing the overhead contact line into multiple such evaluation units. Within each evaluation unit, the vertical residuals at all measurement points are first squared, then averaged, and finally the square root of the average is taken to obtain the RMS value. This index reflects the overall irregularity of the overhead contact line over a continuous length. A larger RMS value indicates greater geometric fluctuations in that section of the contact line, resulting in poorer overall smoothness. This may affect the contact stability between the pantograph and the contact line, as well as the current transmission effect, thus impacting the train's operational stability and safety.

[0041] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for simultaneous detection of wear and geometric irregularities of a rigid catenary, characterized in that, The method comprises the following steps: S1: N high-precision displacement sensors are arranged on a rigid carrier spanning above the overhead contact line, and the sensors are arranged at equal intervals in the transverse direction of the overhead contact line to form a spatial detection array; S2: The rigid carrier is driven to move in the extension direction of the overhead contact line, and real-time distance measurement values of all sensors at continuous spatial positions are synchronously collected; S3: Based on independent historical reference data of each sensor, the wear amount of the contact wire at the position corresponding to each sensor is obtained; S4: Based on the spatial distance relationship of N sensors at the same sampling time, the geometric irregularity amount of the contact wire at the section is obtained.

2. The method for synchronous detection of wear and geometric irregularities of a rigid catenary according to claim 1, characterized in that, The wear parameter is generated by comparing the current measurement value of a single sensor with its historical reference data; The geometric irregularity parameter is generated by the spatial relative relationship of the distance values of N sensors at the same time.

3. The method for synchronous detection of wear and geometric irregularities of a rigid catenary according to claim 2, characterized in that, Step S3 comprises the following steps: S3.1: A dynamic reference mapping relationship is established for each detection point, which associates the historical reference value and the environmental parameter; S3.2: Real-time environmental parameters are obtained, and compensated reference values are generated according to the dynamic reference mapping relationship; S3.3: The difference between the current measurement value and the compensated reference value is calculated as the single-point wear depth; S3.4: Spatial continuity analysis is performed on a plurality of single-point wear depths in the extension direction, and the wear parameter is output.

4. The method for synchronous detection of wear and geometric irregularities of a rigid catenary according to claim 3, characterized in that, The establishment of the dynamic reference mapping relationship in step S3.1 comprises: first, calibrating the initial reference value of each detection point under the standard overhead contact line state, and then determining the environmental compensation coefficient through a temperature and humidity experiment to construct a function model of the reference value and the environmental parameter.

5. The method for synchronous detection of wear and geometric irregularities of rigid catenary according to claim 1, characterized in that, Step S4 comprises the following steps: S4.1: N detection points in the same spatial section are divided into M overlapping analysis units, and each unit contains at least three detection points at continuous spatial positions; S4.2: The geometric deviation amount representing the local deformation of the contact wire is calculated for each unit; S4.3: The geometric deviation amounts of all units are aggregated to generate a section irregularity index.

6. The method for synchronous detection of wear and geometric irregularities of a rigid catenary according to claim 5, characterized in that, The calculation method of the geometric deviation amount satisfies: The analysis unit comprises position points The geometric deviation G is defined by the following functional relationship: wherein is the measured value for the corresponding position.

7. The method for synchronous detection of wear and geometric irregularities of rigid catenary according to claim 1, characterized in that, Step S4 further comprises performing spatial straight line fitting on N measurement values of the same section, calculating the vertical residual error of each measurement point to the fitted straight line, and finally taking the statistical characteristics of the residual error as the overall smoothness index of the section.

8. The method for synchronous detection of wear and geometric irregularities of a rigid catenary according to claim 7, characterized in that, The statistical characteristics include: Local irregularity amplitude: the maximum value of the geometric deviation amount in the sliding analysis window; Continuous irregularity strength: taking a preset length as an evaluation unit, the root mean square value of the vertical residual error is calculated.

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