Method and equipment for synchronously measuring electrical impedance and magnetic flux density of current collection circuit

Abstract

The invention discloses a method and equipment for synchronously measuring impedance and magnetic flux density of a current collection circuit, and relates to the technical field of power system monitoring and measurement. Firstly, measuring points are uniformly selected according to circuit structure distribution, a magnetic flux density probe is arranged, a distribution rationality formula is used for evaluation, and a specific alternating current test signal is injected into one end of the circuit; a stability formula is used for guaranteeing injection stability; a voltage-current method is used for measuring the electrical impedance of each point for multiple times and averaging; an error formula is used for controlling an error; a Hall sensor is used for measuring the magnetic flux density and filtering; and finally storing and analyzing the synchronous data. The method and the device can accurately and synchronously measure the electrical impedance and the magnetic flux density of the current collection circuit, reduce the measurement error, scientifically evaluate the circuit state, optimize the measurement parameters, improve the measurement efficiency, guarantee the reliability of the measurement result, improve the monitoring and management level of the current collection circuit, and maintain the stable operation of a power system.

Description

Technical Field

[0001] The present invention relates to the technical field of power system monitoring and measurement, and in particular to a method and equipment for synchronously measuring electrical impedance and magnetic flux density of a collector line. Background Art

[0002] The collector line plays a key role in collecting and transmitting electric energy in the power system. The stability of its operating state is directly related to the reliability and safety of power supply. Accurately measuring the electrical impedance and magnetic flux density of the collector line is crucial for timely detection of potential line faults, assessment of line health, and optimization of power system operation. However, existing measurement methods and technologies have many shortcomings and are difficult to meet actual needs.

[0003] Traditional electrical impedance measurement methods often only focus on the measurement of a single parameter, and the measurement process is cumbersome and inefficient. For example, when using the bridge method to measure electrical impedance, the line needs to be wired and debugged in a complex manner, the measurement time is long, and it is easily disturbed by external environmental factors, which affects the accuracy and reliability of the measurement results. At the same time, this method cannot be synchronized with the magnetic flux density measurement, and it is difficult to fully and real-time reflect the operating status of the collector line.

[0004] In terms of magnetic flux density measurement, existing technologies mainly rely on single-point measurement or limited-point measurement, which cannot perform comprehensive and continuous monitoring of the collector line. Moreover, the accuracy of the magnetic flux density measurement equipment is limited and it is easily affected by electromagnetic interference and temperature changes, resulting in large measurement errors. In addition, due to the lack of effective synchronization technology, the electrical impedance measurement data and the magnetic flux density measurement data cannot be accurately matched in time, which increases the difficulty of data analysis and fault diagnosis, and it is difficult to accurately determine the fault location and type of the line.

[0005] For fault diagnosis of collector lines, traditional methods mainly make judgments based on the change of a single parameter, such as judging whether the line has a short circuit or open circuit fault based only on the change of electrical impedance. This method ignores the changes in other important parameters such as magnetic flux density, which can easily lead to misjudgment and missed judgment. Moreover, traditional fault diagnosis methods lack in-depth analysis and mining of fault characteristics, cannot accurately predict the development trend of faults, and are difficult to take effective measures to repair them in a timely manner, which may cause more serious power accidents.

[0006] In terms of the operating status assessment of collector lines, the existing assessment methods are mostly based on experience and simple statistical analysis, lacking scientific assessment models and algorithms. These methods cannot comprehensively consider the impact of multiple factors such as electrical impedance, magnetic flux density, temperature, humidity, etc. on the operating status of the line, and the accuracy and reliability of the assessment results are low. In addition, due to the lack of real-time monitoring and dynamic assessment capabilities, potential problems of the line cannot be discovered in time, and effective decision support cannot be provided for the optimized operation of the power system.

[0007] With the continuous development and upgrading of power systems, the structure and operating environment of collector lines are becoming increasingly complex, and the requirements for measurement methods and technologies are becoming higher and higher. Existing measurement methods and technologies can no longer meet the needs of modern power systems for accurate measurement, fault diagnosis and operating status evaluation of collector lines. Therefore, it is of great practical significance to develop a synchronous measurement method and equipment for electrical impedance and magnetic flux density of collector lines, which can effectively solve the problems existing in the existing technology and improve the operation and management level of collector lines. Summary of the invention

[0008] The present invention provides a method and device for synchronously measuring the electrical impedance and magnetic flux density of a collector line to solve the problems mentioned in the above-mentioned prior art.

[0009] In order to achieve the above object, the present invention adopts the following technical solution: a method for synchronously measuring the electrical impedance and magnetic flux density of a collector line, comprising the following steps: Arrange measurement points: According to the structure and distribution characteristics of the collector line, evenly select measurement points on the collector line. The distance between measurement points is set according to the actual situation of the line, generally not more than 10 meters. At the same time, arrange magnetic flux density measurement probes around each measurement point, and use the measurement point distribution rationality formula ,in To measure the rationality of the distribution of points, In order to effectively reflect the number of measurement points of the line characteristics, is the total number of measurement points; Signal injection: Inject an AC test signal of a specific frequency and amplitude at one end of the collector line. The signal frequency is selected between 50Hz-1000Hz, and the signal amplitude is adjusted according to the rated voltage and current of the line, generally 1%-5% of the rated value. Evaluate the stability of the injected signal, where Inject stability into the signal, is the set injection signal strength, is the actual injected signal strength; Impedance measurement: The impedance of each measuring point is measured using the voltage-current method. The voltage U and current I of the injected signal are measured at each measuring point at the same time. According to Ohm's law Calculate the impedance Z, measure at least 5 times, and use the impedance measurement error formula Evaluate the measurement error, where is the impedance measurement error, is the measured electrical impedance value, is the actual electrical impedance value; Magnetic flux density measurement: Use a magnetic flux density measurement probe to measure the magnetic flux density B of each measurement point in real time. The probe uses a Hall sensor with a measurement accuracy of ±0.01mT. Filter the measurement data to remove interference signals. Assess the accuracy of the measurement, where For the accuracy of magnetic flux density measurement, is the measured magnetic flux density value, is the actual magnetic flux density value; Data synchronization processing: Using clock synchronization technology, the synchronization accuracy reaches ±1μs, and the synchronized data is stored and analyzed. Evaluate the synchronization error, where is the data synchronization error, is the timestamp of the electrical impedance measurement data, is the timestamp of the magnetic flux density measurement data, To measure the total duration.

[0010] Furthermore, it also includes: Line fault diagnosis: Based on the measured electrical impedance and magnetic flux density data, the fault feature extraction algorithm is used to extract the fault features. When the electrical impedance suddenly increases or the magnetic flux density fluctuates abnormally, a fault discrimination model is established to determine whether the line has a fault by comparing the normal operating data with the real-time measurement data. The fault diagnosis accuracy formula is used to Evaluate the accuracy of fault diagnosis, where is the fault diagnosis accuracy, is the number of faults correctly diagnosed, is the total number of faults diagnosed; Data analysis and evaluation: Analyze the measured and processed data, evaluate the operating status of the collector line, analyze the changing trends of electrical impedance and magnetic flux density, score the health status of the line by establishing an operating status evaluation model, and use the operating status evaluation accuracy formula Assess the accuracy of the evaluation results, where To evaluate the accuracy of the running status, is the operating status score obtained by measuring the evaluation. Score the actual operational status.

[0011] Furthermore, it also includes: Measurement parameter optimization: According to different collector line types and measurement environments, adjust the frequency and amplitude of signal injection to adapt to the characteristics of different lines. At the same time, optimize the number and distribution of measurement points and use the measurement parameter optimization effect formula Evaluate the optimization effect, where To measure the effect of parameter optimization, is the electrical impedance value measured before optimization, is the electrical impedance value measured after optimization; Verification of measurement results: Compare and verify the measured impedance and magnetic flux density data with known standard data or data obtained by other reliable measurement methods. If the deviation exceeds the set threshold, check and correct the measurement process, and verify the accuracy formula through the measurement results. Evaluate the accuracy of validation, where To verify the accuracy of the measurement results, is the measured data value, is the standard data value.

[0012] Furthermore, the line fault diagnosis uses a wavelet transform algorithm to process the electrical impedance and magnetic flux density data when extracting fault features, and determines the severity and location of the fault by analyzing the wavelet transform coefficients. The wavelet transform fault location accuracy formula is used Evaluate the accuracy of fault location, where is the wavelet transform fault location accuracy, is the fault location measured by wavelet transform, is the actual fault location.

[0013] Furthermore, the data analysis and evaluation adopts the fuzzy comprehensive evaluation method when establishing the operation status evaluation model. By establishing fuzzy membership functions and fuzzy rules, the operation status of the line is comprehensively evaluated. The fuzzy comprehensive evaluation accuracy formula is used. Assess the accuracy of the reviews, where To evaluate the accuracy of fuzzy comprehensive evaluation, is the running status score obtained by fuzzy comprehensive evaluation, Score the actual operational status.

[0014] Furthermore, the measurement parameter optimization uses a genetic algorithm to optimize when adjusting the signal injection frequency. The genetic algorithm simulates natural selection and genetic mechanisms to find the signal injection frequency, and continuously adjusts the frequency parameters according to the electrical impedance and magnetic flux density measurement results of the line. The genetic algorithm is used to optimize the efficiency formula Evaluate optimization efficiency, where To optimize the efficiency of genetic algorithm, is the measurement error before optimization, is the measurement error after optimization.

[0015] Furthermore, the measurement result verification uses statistical analysis methods to calculate the measurement parameters when comparing the data, and determines whether there is a significant difference between the two through hypothesis testing. If there is a significant difference, the measurement process is further checked and corrected, and the reliability formula is verified using statistical analysis. Assess the reliability of the validation, where To verify the reliability of statistical analysis, is the number of correct verifications, is the total number of verifications.

[0016] Further, including: Signal injection unit: used to generate an AC test signal of a specific frequency and amplitude and inject it into the collector line. It uses a signal generator with a frequency accuracy of ±0.1Hz and an amplitude accuracy of ±0.5%. It has a signal conditioning function and can adjust signal parameters according to different line requirements. Electrical impedance measurement unit: It uses the voltage-current measurement method to measure the voltage and current of each measuring point of the collector line at the same time, calculate the electrical impedance value, and is equipped with a voltage sensor and a current sensor. The measurement accuracy reaches ±0.1% and ±0.2% respectively. It has data acquisition and processing functions, and performs filtering and averaging on the measured data. Magnetic flux density measurement unit: Use Hall sensor to measure the magnetic flux density of each measuring point in real time. The sensor measurement accuracy reaches ±0.01mT. It has temperature compensation function to reduce the influence of temperature on the measurement results and transmit the measurement data to the data processing unit in real time. Data processing unit: The processor used has a clock synchronization function to ensure the time synchronization of the electrical impedance measurement data and the magnetic flux density measurement data, store, analyze and process the synchronized data, and realize the line fault diagnosis and operation status evaluation functions; Display and storage unit: used to display measurement results, fault diagnosis information and operation status evaluation results. It has data storage function and can store long-term measurement data to facilitate subsequent analysis and query.

[0017] Compared with the prior art, the present invention has the following beneficial effects: In terms of measurement accuracy, by rationally arranging measurement points, using high-precision sensors and advanced measurement technology, combined with the impedance measurement error formula and the magnetic flux density measurement accuracy formula, the measurement error is effectively reduced to ensure the accuracy of the impedance and magnetic flux density measurement data. At the same time, high-precision clock synchronization technology achieves accurate matching of data in time, and the synchronization effect is evaluated through the data synchronization error formula, providing a reliable basis for subsequent analysis.

[0018] In terms of fault diagnosis, the wavelet transform algorithm is used to extract fault features. Combined with the fault diagnosis accuracy formula and the wavelet transform fault location accuracy formula, it can accurately identify the time, type and location of the fault, improve the accuracy and timeliness of fault diagnosis, facilitate timely maintenance measures, and reduce power outage time and losses.

[0019] When evaluating the operating status, the fuzzy comprehensive evaluation method is used to establish an evaluation model, which comprehensively considers the impact of various factors on the line operating status. The reliability and scientific nature of the evaluation results are improved through the operating status evaluation accuracy formula and the fuzzy comprehensive evaluation accuracy formula, which helps to discover potential line problems in advance and formulate reasonable maintenance plans.

[0020] In the measurement parameter optimization phase, the signal injection frequency is adjusted using a genetic algorithm, and the optimization effect is evaluated using the genetic algorithm optimization efficiency formula. The optimal measurement parameters can be found according to different line characteristics and measurement environments to improve measurement efficiency and accuracy. The measurement result verification adopts a statistical analysis method, and the statistical analysis verification reliability formula is used to evaluate the verification reliability to ensure the credibility of the measurement results.

[0021] In terms of equipment, each unit has a clear division of labor and works in coordination. The signal injection unit can accurately generate and adjust signals, the electrical impedance and magnetic flux density measurement units have high measurement accuracy, the data processing unit realizes data synchronization and analysis, and the display and storage unit facilitates data viewing and management. Overall, the monitoring and management level of the collector line is improved to ensure the stable operation of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The present invention provides a schematic block diagram of a method for synchronously measuring electrical impedance and magnetic flux density of a collector line. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, and it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0026] Reference Figure 1 :A method for synchronously measuring the electrical impedance and magnetic flux density of a collector line comprises the following steps: Arrangement of measurement points: It is necessary to operate according to the structure and distribution characteristics of the collector line. The structure of the collector line is often complex and diverse, including different directions, branching conditions, etc., and its distribution may cover a large area. These factors have an important impact on the selection of measurement points. Specifically, multiple measurement points should be evenly selected on the collector line. The reason for emphasizing uniform selection is to obtain parameter information at different positions of the line in a comprehensive and balanced manner. Taking into account factors such as line length and branching conditions, the spacing between measurement points needs to be set according to the actual situation of the line, generally not exceeding 10 meters. Shorter spacing can capture changes in line parameters more carefully. For areas with complex line structures and frequent parameter changes, the spacing can be appropriately reduced; while in more regular parts with relatively stable parameter changes, relatively larger spacing can be used.

[0027] At the same time, magnetic flux density measuring probes are arranged at appropriate locations around each measuring point. The placement of the probe is crucial to ensure that it can accurately measure the magnetic flux density at that point. This requires comprehensive consideration of factors such as the distance and angle between the probe and the line to avoid interference from surrounding environmental factors on the measurement results. Use the measurement point distribution rationality formula (in To measure the rationality of the distribution of points, In order to effectively reflect the number of measurement points of the line characteristics, is the total number of measuring points) to evaluate the rationality of the measurement point layout.

[0028] Signal injection: Inject an AC test signal of a specific frequency and amplitude at one end of the collector line. The selection of signal frequency has a strict range and basis, and the frequency selection is between 50Hz - 1000Hz, which needs to be determined according to the characteristics of the line. Different collector lines have different response characteristics to signals of different frequencies due to differences in their length, material, structure and other factors. Reasonable selection of frequency can enable the signal to better reflect the parameter information of the line when it propagates in the line, thereby improving the accuracy of the measurement. For example, for a shorter line, a higher frequency signal may better reflect its characteristics; while for a longer line, a lower frequency signal may have a better propagation effect.

[0029] The signal amplitude also needs to be fine-tuned. Its amplitude is adjusted according to the rated voltage and current of the line, generally 1% - 5% of the rated value. Such an amplitude setting can ensure that the signal has sufficient strength to obtain clear measurement data without having too much impact on the normal operation of the line. (in Inject stability into the signal, is the set injection signal strength, is the actual injected signal strength) to evaluate the stability of the injected signal.

[0030] Electrical impedance measurement: The voltage-current method is used to accurately measure the electrical impedance of each measurement point. At each measurement point, the voltage U and current I of the injected signal are measured synchronously. This simultaneous measurement method is to ensure that the acquired data can truly reflect the electrical characteristics of the measurement point at the same time, because the voltage and current in the line may change dynamically over time, and only simultaneous measurement can ensure the accuracy and consistency of the data. According to Ohm's law Calculate the impedance Z. In order to effectively reduce the measurement error and improve the reliability of the measurement results, the method of taking the average value of multiple measurements is adopted, and the number of measurements is not less than 5. Multiple measurements can offset the influence of accidental errors to a certain extent and make the measurement results closer to the true value. By performing statistical analysis on multiple measurement data and calculating the average value, a more accurate impedance measurement value can be obtained. Use the impedance measurement error formula (in is the impedance measurement error, is the measured electrical impedance value, The formula is used to evaluate the measurement error. The formula intuitively reflects the degree of deviation between the measured value and the actual value in the form of a percentage. By calculating the measurement error, the accuracy of the measurement result can be quantitatively evaluated. If the measurement error exceeds the allowable range, it is necessary to further check the measuring instrument, measurement method or measurement environment and other factors to find out the cause of the error and make corrections to ensure that the accuracy of the measurement result meets the requirements.

[0031] Magnetic flux density measurement: Magnetic flux density measurement is an important means to fully understand the electromagnetic characteristics of the collector circuit. During the measurement process, a magnetic flux density measurement probe is used to measure the magnetic flux density B of each measuring point in real time. These probes use highly sensitive Hall sensors. Hall sensors have the characteristics of fast response speed and high sensitivity. They can accurately sense changes in the magnetic field. Their measurement accuracy can reach ±0.01mT, which provides a strong hardware guarantee for obtaining accurate magnetic flux density data. In the actual measurement environment, there will inevitably be various interference signals. These interference signals may affect the measurement results and cause deviations in the measurement data. In order to improve the accuracy of the measurement, the measurement data needs to be filtered. Filtering can effectively remove interference signals and retain the true magnetic flux density signal. Through specific filtering algorithms and circuits, the measurement data can be screened and processed according to the differences in frequency, amplitude, etc. between the interference signal and the useful signal, so as to obtain purer and more accurate measurement data. Through the magnetic flux density measurement accuracy formula (in For the accuracy of magnetic flux density measurement, is the measured magnetic flux density value, The accuracy of the measurement is evaluated by using the formula (where θ is the actual magnetic flux density value). This formula is similar to the impedance measurement error formula, and also measures the degree of deviation between the measured value and the actual value in the form of a percentage. By calculating this accuracy index, possible problems in the measurement process, such as sensor failure, excessive interference, etc., can be discovered in a timely manner, and corresponding measures can be taken to improve them, so as to ensure the reliability and accuracy of the magnetic flux density measurement results, and provide accurate data support for subsequent electromagnetic analysis and fault diagnosis of the collector circuit.

[0032] Data synchronization processing: To ensure the synchronization of electrical impedance measurement data and magnetic flux density measurement data in time, high-precision clock synchronization technology is used. The application of this technology is extremely important because in the measurement scenario of the collector line, the changes in electrical impedance and magnetic flux density may be closely related to time. If the data of the two are not synchronized in time, the subsequent comprehensive analysis of line parameters will lose its meaning and cannot accurately reflect the actual operating status of the line. The synchronization accuracy reaches ±1μs. Such high accuracy can minimize the measurement error and analysis deviation caused by time difference.

[0033] After data synchronization is completed, the synchronized data is stored and analyzed. The purpose of storing data is to facilitate subsequent in-depth research and comparative analysis, while the purpose of analyzing data is to mine relevant information about line operation, such as fault diagnosis, status evaluation, etc. (in is the data synchronization error, is the timestamp of the electrical impedance measurement data, is the timestamp of the magnetic flux density measurement data, The formula is used to evaluate the synchronization error by calculating the ratio of the difference between the two measurement data timestamps and the total measurement time, and quantifies the data synchronization error. If the synchronization error is too large, it may affect the accurate judgment of the line parameters. At this time, it is necessary to check and adjust the clock synchronization technology or related equipment to ensure the accuracy of data synchronization and provide a reliable basis for subsequent analysis and decision-making based on synchronization data.

[0034] The present invention also includes: Line fault diagnosis: Based on the measured electrical impedance and magnetic flux density data, the fault feature extraction algorithm is used to extract the fault features. For example, when the electrical impedance suddenly increases or the magnetic flux density fluctuates abnormally, there may be a line fault. A fault discrimination model is established to determine whether there is a line fault by comparing the normal operation data with the real-time measurement data. Use the fault diagnosis accuracy formula (in is the fault diagnosis accuracy, is the number of faults correctly diagnosed, The accuracy of fault diagnosis is evaluated by using the total number of diagnosed faults.

[0035] Data analysis and evaluation: Conduct in-depth analysis of measured and processed data to evaluate the operating status of the collector line. Analyze the changing trends of electrical impedance and magnetic flux density to determine whether the line has problems such as aging and short circuit. By establishing an operating status evaluation model, comprehensively consider factors such as electrical impedance, magnetic flux density, and temperature to score the health status of the line. Use the operating status evaluation accuracy formula (in To evaluate the accuracy of the running status, is the operating status score obtained by measuring the evaluation. Score the actual operating status) to evaluate the accuracy of the evaluation results.

[0036] The present invention also includes: Measurement parameter optimization: Optimize measurement parameters according to different collector line types and measurement environments. Adjust the frequency and amplitude of signal injection to adapt to the characteristics of different lines. For example, for long-distance collector lines, appropriately increase the signal frequency and amplitude to enhance the signal transmission capacity. At the same time, optimize the number and distribution of measurement points to improve measurement accuracy and efficiency. Use the measurement parameter optimization effect formula (in To measure the effect of parameter optimization, is the electrical impedance value measured before optimization, The optimization effect is evaluated by measuring the electrical impedance value after optimization.

[0037] Verification of measurement results: Compare and verify the measured impedance and magnetic flux density data with known standard data or data obtained by other reliable measurement methods. If the deviation exceeds the set threshold (usually ±5%), the measurement process is checked and corrected. Verify the accuracy formula through measurement results (in To verify the accuracy of the measurement results, is the measured data value, is the standard data value) to evaluate the accuracy of the validation.

[0038] In the present invention, the line fault diagnosis uses a wavelet transform algorithm to process the electrical impedance and magnetic flux density data when extracting fault features. Wavelet transform can effectively extract mutation features in the signal and accurately identify the time and type of fault. The severity and location of the fault are determined by analyzing the wavelet transform coefficients. The wavelet transform fault location accuracy formula is: (in is the wavelet transform fault location accuracy, is the fault location measured by wavelet transform, The actual fault location is used to evaluate the accuracy of fault location.

[0039] In the present invention, the data analysis and evaluation adopts fuzzy comprehensive evaluation method when establishing the operation status evaluation model. Consider the influence of multiple factors on the line operation status, such as electrical impedance, magnetic flux density, temperature, humidity, etc. By establishing fuzzy membership functions and fuzzy rules, the operation status of the line is comprehensively evaluated. The fuzzy comprehensive evaluation accuracy formula is used (in To evaluate the accuracy of fuzzy comprehensive evaluation, is the running status score obtained by fuzzy comprehensive evaluation, Score the actual operating status) to assess the accuracy of the evaluation.

[0040] In the present invention, the measurement parameter optimization uses a genetic algorithm to optimize when adjusting the signal injection frequency. The genetic algorithm simulates natural selection and genetic mechanisms to find the optimal signal injection frequency. According to the electrical impedance and magnetic flux density measurement results of the line, the frequency parameters are continuously adjusted to minimize the measurement error. Using the genetic algorithm to optimize the efficiency formula (in To optimize the efficiency of genetic algorithm, is the measurement error before optimization, is the measured error after optimization) to evaluate the optimization efficiency.

[0041] In the present invention, the measurement result verification adopts statistical analysis method when comparing data. Calculate the statistical parameters such as mean and variance of the measurement data and standard data, and judge whether there is a significant difference between the two through hypothesis testing. If there is a significant difference, further check and correct the measurement process. Use statistical analysis to verify the reliability formula (in To verify the reliability of statistical analysis, is the number of correct verifications, is the total number of verifications) to evaluate the reliability of the verification.

[0042] The present invention includes: Signal injection unit: used to generate an AC test signal of a specific frequency and amplitude, and accurately inject it into the collector line. This unit uses a high-precision signal generator with a frequency accuracy of up to ±0.1Hz, which means that when the signal is generated, the frequency fluctuation range is extremely small, which can provide a stable and accurate frequency reference for the measurement. The amplitude accuracy reaches ±0.5%, which ensures the accuracy of the signal strength, so that the signal injected into the line meets the measurement requirements. In addition, this unit also has a signal conditioning function, which can flexibly adjust the frequency, amplitude and other parameters of the signal according to the specific needs of different collector lines. Regardless of the line length, material or structure, the signal injection unit can ensure that the test signal can effectively excite the line by adjusting the parameters, providing a reliable prerequisite for subsequent electrical impedance and magnetic flux density measurements.

[0043] Impedance measurement unit: The impedance measurement unit uses the voltage-current measurement method to accurately measure the voltage and current of each measuring point of the collector line at the same time, and then calculates the impedance value. In order to achieve high-precision measurement, the unit is equipped with high-precision voltage sensors and current sensors, of which the measurement accuracy of the voltage sensor reaches ±0.1%, and the measurement accuracy of the current sensor reaches ±0.2%. These high-precision sensors can accurately capture the voltage and current changes at the measuring point, providing a reliable data basis for the calculation of impedance. In addition, the unit also has powerful data acquisition and processing functions. In terms of data acquisition, it can quickly and stably obtain measurement data; in terms of data processing, the measurement data can be filtered to remove interference signals and improve the purity of the data. It can also be averaged. By taking the average value of multiple measurements, the measurement error can be reduced and the accuracy and reliability of the measurement results can be improved.

[0044] Magnetic flux density measurement unit: Use highly sensitive Hall sensors to measure the magnetic flux density of each measuring point in real time. The sensor has a measurement accuracy of ±0.01mT, can keenly sense subtle changes in the magnetic field, and provide high-precision data for the measurement of magnetic flux density. At the same time, the sensor has a temperature compensation function. Since temperature changes may affect the measurement results of the Hall sensor, the temperature compensation function can automatically adjust according to changes in ambient temperature, reduce the interference of temperature factors on the measurement results, and ensure that accurate magnetic flux density measurements can be obtained under different temperature conditions. The measured data can be transmitted to the data processing unit in real time to provide timely information support for subsequent data processing and analysis.

[0045] Data processing unit: It uses a high-performance processor and is the core processing part of the entire measurement system. It has a high-precision clock synchronization function, which is essential to ensure the time synchronization of the impedance measurement data and the flux density measurement data. In the measurement of the collector line, only by ensuring the temporal consistency of the two data can the operation status of the line be accurately analyzed. The unit performs comprehensive storage, analysis and processing of the synchronized data. In terms of storage, it can safely and stably save a large amount of data; in terms of analysis, it uses advanced algorithms and models to deeply mine the data to realize functions such as line fault diagnosis and operation status evaluation. Through the analysis of the measurement data, it is possible to timely discover the potential fault hazards of the line, evaluate the operation health of the line, and provide a scientific basis for the maintenance and management of the line.

[0046] Display and storage unit: used to display measurement results, fault diagnosis information, and operating status evaluation results. Through the intuitive interface, operators can clearly understand the various parameters of the collector line, whether there are faults, and the current operating status and other key information. At the same time, the unit has a large-capacity data storage function and can store long-term measurement data. These historical data are of great value for subsequent in-depth analysis and query. For example, by analyzing historical data, the law of line operation can be summarized, and possible problems in the future can be predicted, providing strong data support for the long-term maintenance and optimization of the line.

[0047] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for synchronously measuring electrical impedance and magnetic flux density of a collector line, characterized in that: The following steps are involved: Arrange measurement points: According to the structure and distribution characteristics of the collector line, evenly select measurement points on the collector line. The distance between measurement points is set according to the actual situation of the line and does not exceed 10 meters. At the same time, arrange magnetic flux density measurement probes around each measurement point and use the measurement point distribution rationality formula ,in To measure the rationality of the distribution of points, In order to effectively reflect the number of measurement points of the line characteristics, is the total number of measurement points; Signal injection: Inject an AC test signal of a specific frequency and amplitude at one end of the collector line. The signal frequency is selected between 50Hz-1000Hz, and the signal amplitude is adjusted according to the rated voltage and current of the line, which is 1%-5% of the rated value. The signal injection stability formula is used Evaluate the stability of the injected signal, where Inject stability into the signal, is the set injection signal strength, is the actual injected signal strength; Impedance measurement: The impedance of each measuring point is measured using the voltage-current method. The voltage U and current I of the injected signal are measured at each measuring point at the same time. According to Ohm's law Calculate the impedance Z, measure at least 5 times, and use the impedance measurement error formula Evaluate the measurement error, where is the impedance measurement error, is the measured electrical impedance value, is the actual electrical impedance value; Magnetic flux density measurement: Use a magnetic flux density measurement probe to measure the magnetic flux density B of each measurement point in real time. The probe uses a Hall sensor with a measurement accuracy of ±0.01mT. Filter the measurement data to remove interference signals. Assess the accuracy of the measurement, where For the accuracy of magnetic flux density measurement, is the measured magnetic flux density value, is the actual magnetic flux density value; Data synchronization processing: Using clock synchronization technology, the synchronization accuracy reaches ±1μs, and the synchronized data is stored and analyzed. Evaluate the synchronization error, where is the data synchronization error, is the timestamp of the electrical impedance measurement data, is the timestamp of the magnetic flux density measurement data, To measure the total duration.

2. The method for synchronously measuring collector line electrical impedance and magnetic flux density according to claim 1, characterized in that: Also includes: Line fault diagnosis: Based on the measured electrical impedance and magnetic flux density data, the fault feature extraction algorithm is used to extract the fault features. When the electrical impedance suddenly increases or the magnetic flux density fluctuates abnormally, a fault discrimination model is established to determine whether the line has a fault by comparing the normal operating data with the real-time measurement data. The fault diagnosis accuracy formula is used to Evaluate the accuracy of fault diagnosis, where is the fault diagnosis accuracy, is the number of faults correctly diagnosed, is the total number of faults diagnosed; Data analysis and evaluation: Analyze the measured and processed data, evaluate the operating status of the collector line, analyze the changing trends of electrical impedance and magnetic flux density, score the health status of the line by establishing an operating status evaluation model, and use the operating status evaluation accuracy formula Assess the accuracy of the evaluation results, where To evaluate the accuracy of the running status, is the operating status score obtained by measuring the evaluation. Score the actual operational status.

3. The method for synchronously measuring collector line electrical impedance and magnetic flux density according to claim 1, characterized in that: Also includes: Measurement parameter optimization: According to different collector line types and measurement environments, adjust the frequency and amplitude of signal injection to adapt to the characteristics of different lines. At the same time, optimize the number and distribution of measurement points and use the measurement parameter optimization effect formula Evaluate the optimization effect, where To measure the effect of parameter optimization, is the electrical impedance value measured before optimization, is the electrical impedance value measured after optimization; Verification of measurement results: Compare and verify the measured impedance and magnetic flux density data with known standard data or data obtained by other reliable measurement methods. If the deviation exceeds the set threshold, check and correct the measurement process, and verify the accuracy formula through the measurement results. Evaluate the accuracy of validation, where To verify the accuracy of the measurement results, is the measured data value, is the standard data value.

4. The method for synchronously measuring collector line electrical impedance and magnetic flux density according to claim 2, characterized in that: The line fault diagnosis uses wavelet transform algorithm to process the electrical impedance and magnetic flux density data when extracting fault features, and determines the severity and location of the fault by analyzing the wavelet transform coefficients. The wavelet transform fault location accuracy formula is used Evaluate the accuracy of fault location, where is the wavelet transform fault location accuracy, is the fault location measured by wavelet transform, is the actual fault location.

5. The method for synchronously measuring collector line electrical impedance and magnetic flux density according to claim 2, characterized in that: The data analysis and evaluation adopts fuzzy comprehensive evaluation method when establishing the operation status evaluation model. By establishing fuzzy membership function and fuzzy rules, the operation status of the line is comprehensively evaluated. The fuzzy comprehensive evaluation accuracy formula is used. Assess the accuracy of the reviews, where To evaluate the accuracy of fuzzy comprehensive evaluation, is the running status score obtained by fuzzy comprehensive evaluation, Score the actual operational status.

6. The method for synchronously measuring collector line electrical impedance and magnetic flux density according to claim 3, characterized in that: The measurement parameter optimization adopts a genetic algorithm to optimize when adjusting the signal injection frequency. The genetic algorithm simulates natural selection and genetic mechanism to find the signal injection frequency, and continuously adjusts the frequency parameters according to the measurement results of the line's electrical impedance and magnetic flux density. The genetic algorithm is used to optimize the efficiency formula Evaluate optimization efficiency, where To optimize the efficiency of genetic algorithm, is the measurement error before optimization, is the measurement error after optimization.

7. The method for synchronously measuring collector line electrical impedance and magnetic flux density according to claim 3, characterized in that: The measurement result verification uses statistical analysis methods to calculate the measurement parameters when comparing data, and uses hypothesis testing to determine whether there is a significant difference between the two. If there is a significant difference, the measurement process is checked and corrected, and the reliability formula is verified using statistical analysis. Assess the reliability of the validation, where To verify the reliability of statistical analysis, is the number of correct verifications, is the total number of verifications.

8. A system using the method for synchronously measuring electrical impedance and magnetic flux density of a collector line according to any one of claims 1 to 7, characterized in that: include: Signal injection unit: used to generate an AC test signal of a specific frequency and amplitude and inject it into the collector line. It uses a signal generator with a frequency accuracy of ±0.1Hz and an amplitude accuracy of ±0.5%. It has a signal conditioning function and can adjust signal parameters according to different line requirements. Electrical impedance measurement unit: It uses the voltage-current measurement method to measure the voltage and current of each measuring point of the collector line at the same time, calculate the electrical impedance value, and is equipped with a voltage sensor and a current sensor. The measurement accuracy reaches ±0.1% and ±0.2% respectively. It has data acquisition and processing functions, and performs filtering and averaging on the measured data. Magnetic flux density measurement unit: Use Hall sensor to measure the magnetic flux density of each measuring point in real time. The sensor measurement accuracy reaches ±0.01mT. It has temperature compensation function to reduce the influence of temperature on the measurement results and transmit the measurement data to the data processing unit in real time. Data processing unit: The processor used has a clock synchronization function to ensure the time synchronization of the electrical impedance measurement data and the magnetic flux density measurement data, store, analyze and process the synchronized data, and realize the line fault diagnosis and operation status evaluation functions; Display and storage unit: used to display measurement results, fault diagnosis information and operation status evaluation results. It has data storage function and can store long-term measurement data to facilitate subsequent analysis and query.

Images