Traveling-wave positioning sensor inspection system and method

Abstract

The present application discloses a traveling-wave positioning sensor inspection system and method. The system comprises: an industrial control computer, a signal source generation apparatus, and a signal recording apparatus, the signal source generation apparatus and the signal recording apparatus being separately connected to the industrial control computer. The signal source generation apparatus generates a first electrical signal having a signal frequency greater than a preset frequency threshold. The signal recording apparatus acquires a second electrical signal obtained by a traveling-wave positioning sensor after performing transformation on the basis of the first electrical signal. On the basis of the second electrical signal, the industrial control computer determines an inspection result of the traveling-wave positioning sensor, Thus, traceability and verification of the accuracy of the traveling-wave positioning sensor is achieved, and the inspection result can also assist in improving a fault locating capability of the sensor.

Description

A traveling wave positioning sensor detection system and method Technical Field

[0001] This application relates to the field of power distribution network operation analysis technology, and in particular to a traveling wave positioning sensor detection system and method. Background Technology

[0002] With the accelerated construction of new power systems, the distribution network, the "last mile" of power grid construction, has become a key focus of these systems. New distribution networks are crucial for the large-scale integration of renewable energy, but their structures are more complex and typical fault characteristics are more difficult to identify. As an important indicator of high-quality power development, the reliability of power supply from distribution networks is receiving increasing attention and concern from the government, society, and the public.

[0003] In my country's medium-voltage distribution network, overhead lines dominate, and single-phase grounding faults account for over 80% of all distribution network faults. To improve the safe operation of distribution network lines, fault location is currently the primary technical means of operation and maintenance. Accurate fault location after a fault occurs is a key technology for ensuring rapid repair of faulty lines and rapid restoration of power supply to non-faulty areas. Currently, fault location in distribution networks can only be achieved by selecting the line or section, which is particularly problematic for long-distance distribution lines crossing forests and grasslands, significantly hindering rapid fault handling and seriously affecting power safety. Although fault location and insulation defect early warning technologies based on traveling waves can achieve fault location in high-voltage transmission networks, the complex structure of distribution networks, numerous line branches, various neutral grounding methods, complex fault types, and the difficulty in identifying faults, coupled with weak traveling wave signals, make accurate fault location difficult in many areas, leading to challenges in fault detection, handling, and early warning.

[0004] Traveling wave-based fault analysis technology can achieve accurate fault location. However, the traveling wave location sensors used for fault location in distribution networks currently lack effective calibration, and there is no relevant power source to test them, making it impossible to trace and verify the accuracy of traveling wave location sensors in distribution networks. Summary of the Invention

[0005] This application provides a traveling wave positioning sensor detection system and method. The traveling wave positioning sensor is detected by a high-frequency signal source generated by a signal source generator. This can enable the traceability and verification of the accuracy of the traveling wave positioning sensor, thereby helping to improve the fault location capability of the traveling wave positioning sensor.

[0006] The technical solution of this application is implemented as follows:

[0007] In a first aspect, this application provides a traveling wave positioning sensor detection system, including: an industrial control computer, a signal source generating device, and a signal receiving device, wherein the signal source generating device and the signal receiving device are respectively connected to the industrial control computer;

[0008] The signal source generating device is used to generate a first electrical signal with a signal frequency greater than a first frequency threshold, and send the first electrical signal to the traveling wave positioning sensor;

[0009] The signal acquisition device is used to acquire the second electrical signal after the traveling wave positioning sensor has transformed the first electrical signal, and to send the second electrical signal to the industrial control computer; the amplitude of the second electrical signal is less than the amplitude of the first electrical signal.

[0010] The industrial control computer is used to acquire the second electrical signal and determine the detection result of the traveling wave positioning sensor based on the second electrical signal.

[0011] Secondly, this application provides a traveling wave positioning sensor detection method, applied to the traveling wave positioning sensor detection system provided in the embodiments of this application. The method includes: the signal source generating device generating a first electrical signal with a signal frequency greater than a first frequency threshold, and sending the first electrical signal to the traveling wave positioning sensor;

[0012] The signal acquisition device collects the second electrical signal obtained by the traveling wave positioning sensor after transforming the first electrical signal, and sends the second electrical signal to the industrial control computer; the amplitude of the second electrical signal is less than the amplitude of the first electrical signal.

[0013] The industrial control computer acquires the second electrical signal collected by the signal recording device, and determines the detection result of the traveling wave positioning sensor based on the second electrical signal.

[0014] This application provides a traveling wave positioning sensor detection system and method. The traveling wave positioning sensor detection system includes: an industrial control computer, a signal source generator, and a signal receiving device. The signal source generator and the signal receiving device are respectively connected to the industrial control computer. The signal source generator is used to generate a first electrical signal with a frequency greater than a first frequency threshold and send the first electrical signal to the traveling wave positioning sensor. The signal receiving device is used to collect a second electrical signal from the traveling wave positioning sensor after transformation processing based on the first electrical signal and send the second electrical signal to the industrial control computer. The amplitude of the second electrical signal is less than the amplitude of the first electrical signal. The industrial control computer is used to acquire the second electrical signal collected by the signal receiving device and determine the detection result of the traveling wave positioning sensor based on the second electrical signal. In this way, a first electrical signal with a frequency greater than a preset frequency threshold is generated by a signal source generator, a second electrical signal after the traveling wave positioning sensor has transformed and processed based on the first electrical signal is collected by a signal receiving device, and the detection result of the traveling wave positioning sensor is determined by an industrial control computer based on the second electrical signal. This realizes the traceability and verification of the accuracy of the traveling wave positioning sensor, and the detection result can help improve the fault location capability of the traveling wave positioning sensor. Attached Figure Description

[0015] Figure 1 is a schematic diagram of a traveling wave positioning sensor detection system provided in an embodiment of this application;

[0016] Figure 2 is a schematic diagram of a signal source generating device provided in an embodiment of this application;

[0017] Figure 3 is a schematic diagram of a high-frequency waveform recorder provided in an embodiment of this application;

[0018] Figure 4 is a schematic diagram of a structure for implementing multi-station detection according to an embodiment of this application;

[0019] Figure 5 is a flowchart illustrating a traveling wave positioning sensor detection method provided in an embodiment of this application;

[0020] Figure 6 is a schematic diagram of a power distribution network traveling wave positioning sensor detection system provided in an embodiment of this application;

[0021] Figure 7 is a flowchart illustrating a measurement mode implementation method for a high-frequency waveform recorder provided in an embodiment of this application;

[0022] Figure 8 is a flowchart illustrating a method for implementing the recording mode of a high-frequency waveform recorder according to an embodiment of this application;

[0023] Figure 9 is a flowchart illustrating an automatic closed-loop testing method for a traveling wave positioning sensor in a power distribution network, provided in an embodiment of this application.

[0024] Figure 10 is a flowchart illustrating a method for fitting and analyzing the secondary high-frequency signal of a traveling wave positioning sensor in a power distribution network, as provided in an embodiment of this application. Detailed Implementation

[0025] In order to gain a more detailed understanding of the features and technical content of the embodiments of this application, the implementation of the embodiments of this application will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for reference and illustration only and are not intended to limit the embodiments of this application.

[0026] This application provides a traveling wave positioning sensor detection system, as shown in Figure 1. The traveling wave positioning sensor detection system 100 may include: an industrial control computer 101, a signal source generator 102, and a signal receiving device 103.

[0027] In some embodiments, the signal source generating device 102 can be used to generate a first electrical signal with a signal frequency greater than a first frequency threshold and send the first electrical signal to the traveling wave positioning sensor.

[0028] In some embodiments, the first frequency threshold can be set by test software installed on the industrial control computer 101. The first frequency threshold can be determined based on the frequency parameters of the traveling wave positioning sensor under test, such as by the sampling frequency of the traveling wave positioning sensor. The first frequency threshold can be the frequency value of voltage signal, current signal, etc., and the first frequency value can be 500 kHz, 1000 kHz, etc.

[0029] In some embodiments, since the signal frequency of the first electrical signal is greater than the first frequency threshold, the first electrical signal is a high-frequency signal. The first electrical signal can be a high-frequency analog signal, for example, the first electrical signal can be a high-frequency analog voltage signal or a high-frequency analog current signal, etc.; the first electrical signal can be an AC signal, correspondingly, the first electrical signal can be an AC voltage signal or an AC current signal.

[0030] In some embodiments, the signal source generating device 102 can be electrically connected to the traveling wave positioning sensor. After generating the first electrical signal, the signal source generating device can transmit the first electrical signal to the traveling wave positioning sensor through the electrical connection.

[0031] In some embodiments, the signal source generating device 102 can generate a first electrical signal with a signal frequency greater than a first frequency threshold based on the control of the industrial control computer 101. For example, the industrial control computer 101 sends information such as the frequency and amplitude of the first electrical signal to the signal source generating device 102. After receiving such information, the signal source generating device 102 can trigger the generation of the first electrical signal.

[0032] In some embodiments, the signal acquisition device 103 can be used to acquire the second electrical signal after the traveling wave positioning sensor has transformed based on the first electrical signal, and send the second electrical signal to the industrial control computer 101.

[0033] In some embodiments, the signal receiving device 103 and the traveling wave positioning sensor can establish an electrical connection. The traveling wave positioning sensor can convert the amplitude of the input first electrical signal through its own transformation ratio parameters to obtain a second electrical signal. The signal type of the second electrical signal can be the same as that of the first electrical signal. For example, if the first electrical signal is an analog current signal, then the second electrical signal is also an analog current signal; if the first electrical signal is an analog voltage signal, then the second electrical signal is also an analog voltage signal.

[0034] In some embodiments, the signal frequency of the second electrical signal is the same as that of the first electrical signal, but the amplitudes of the first and second electrical signals are different, with the amplitude of the second electrical signal being smaller than that of the first electrical signal. For example, if both the first and second electrical signals are alternating current signals, then the current amplitude of the first electrical signal is greater than that of the second electrical signal.

[0035] In some embodiments, the traveling wave positioning sensor can transmit its own output second electrical signal to the signal receiving device 103, or the signal receiving device 103 can actively collect the second electrical signal output by the sensor. After acquiring the second electrical signal, the signal receiving device 103 can send the second electrical signal to the industrial control computer 101.

[0036] In some embodiments, the industrial computer 101 can be used to acquire the second electrical signal and determine the detection result of the traveling wave positioning sensor based on the second electrical signal.

[0037] In some embodiments, the detection result of the traveling wave positioning sensor may include whether the sampling frequency of the traveling wave positioning sensor is accurate, for example, whether the actual sampling frequency of the traveling wave positioning sensor is consistent with the sampling frequency specified in the factory parameters of the traveling wave positioning sensor. The detection result of the traveling wave positioning sensor may also include the sampling accuracy of the traveling wave positioning sensor.

[0038] In some embodiments, the industrial control computer 101 can analyze and process the acquired second electrical signal to calibrate the sampling frequency of the traveling wave positioning sensor, and / or determine the sampling accuracy of the traveling wave positioning sensor. The sampling frequency of the traveling wave positioning sensor can be its maximum sampling frequency.

[0039] In this embodiment, the traveling wave positioning sensor detection system includes: an industrial control computer, a signal source generator, and a signal receiving device. The signal source generator and the signal receiving device are respectively connected to the industrial control computer. The signal source generator generates a first electrical signal with a frequency greater than a first frequency threshold and sends the first electrical signal to the traveling wave positioning sensor. The signal receiving device collects a second electrical signal from the traveling wave positioning sensor after processing the first electrical signal and sends the second electrical signal to the industrial control computer. The amplitude of the second electrical signal is less than the amplitude of the first electrical signal. The industrial control computer acquires the second electrical signal collected by the signal receiving device and determines the detection result of the traveling wave positioning sensor based on the second electrical signal. Thus, by generating a first electrical signal with a frequency greater than a preset frequency threshold using the signal source generator, collecting the second electrical signal from the traveling wave positioning sensor after processing the first electrical signal using the signal receiving device, and determining the detection result of the traveling wave positioning sensor based on the second electrical signal using the industrial control computer, the system achieves traceability and verification of the accuracy of the traveling wave positioning sensor. Furthermore, the detection result can help improve the fault location capability of the traveling wave positioning sensor.

[0040] In some embodiments of this application, the industrial control computer 101 is further configured to determine the information of the first electrical signal based on the parameters of the traveling wave positioning sensor, and send the information of the first electrical signal to the signal source generating device 102, so that the signal source generating device 103 generates the first electrical signal based on the information of the first electrical signal.

[0041] In some embodiments, the information of the first electrical signal may include information such as the frequency, amplitude, and waveform of the first electrical signal; the parameters of the traveling wave positioning sensor may include the current transformer (CT) ratio and frequency of the traveling wave positioning sensor; the industrial control computer 101 is equipped with test software, which can be used to edit test cases for the traveling wave positioning sensor, including the information of the first electrical signal (such as frequency, amplitude, waveform, etc.).

[0042] In some embodiments, after the information of the first electrical signal is edited by the test software of the industrial control computer 101, the information of the first electrical signal can be sent to the signal source generator 102. After receiving the information of the first electrical signal, the signal source generator can generate the first electrical signal according to the information of the first electrical signal.

[0043] Understandably, by determining the information of the first electrical signal based on the parameters of the traveling wave positioning sensor, the information of the first electrical signal of different traveling wave positioning sensors can be freely set on the industrial control computer, or multiple different information of the first electrical signal can be set for the same traveling wave positioning sensor under test, so as to realize the flexible setting of the test signal for the traveling wave positioning sensor.

[0044] In some embodiments of this application, the industrial control computer 101 is also used to determine a fault signal threshold and a signal error threshold, so as to analyze and process the second electrical signal based on the fault signal threshold and the signal error threshold, and determine the detection result of the traveling wave positioning sensor.

[0045] In some embodiments, the fault signal threshold can be a current value, voltage value, etc., used to trigger the acquisition of the fault signal. For example, when the fault signal is a current, the fault signal threshold can be 3 amperes (A), 4 A, etc. The signal error threshold can be the maximum permissible error between the amplitude of the signal acquired by the traveling wave positioning sensor and the amplitude of the test signal generated by the signal source generator 102.

[0046] In some embodiments, the fault signal threshold and signal error threshold can also be determined by the parameters of the traveling wave positioning sensor, and can be edited by the test software of the industrial control computer 101. After editing the fault signal threshold and signal error threshold through the test software, the fault signal threshold and signal error threshold can be saved. After receiving the second electrical signal sent by the signal receiving device, the second electrical signal can be converted to obtain a third electrical signal, for example, by converting the secondary signal (second electrical signal) into a primary signal (first electrical signal) through the CT ratio. The third electrical signal is truncated according to the fault signal threshold to obtain the amplitude of the truncated electrical signal. The amplitude of the truncated electrical signal is compared with the test signal (first electrical signal) to determine the absolute value of the difference between the amplitude of the truncated electrical signal and the amplitude of the test signal. The signal error threshold is determined based on the absolute value of the difference to determine the detection result of the traveling wave positioning sensor. The detection result may include whether the frequency of the traveling wave positioning sensor is accurate, the sampling accuracy, etc.

[0047] It is understandable that by determining the fault signal threshold and signal error threshold through the industrial control computer, the second electrical signal can be analyzed and processed based on the fault signal threshold and signal error threshold after it is acquired, thereby obtaining the detection result of the traveling wave positioning sensor.

[0048] In some embodiments of this application, the signal source generating device 102 includes a signal generator 1021, an amplitude controller 1022, an operational amplifier mixer 1023, a high-frequency amplifier 1024, and a current detector 1025 connected in sequence.

[0049] In some embodiments, the signal generator 1021 can be used to generate traveling wave waveform data, which can be waveform data of an AC current signal or waveform data of an AC voltage signal, etc.

[0050] In some embodiments, the signal generator 1021 can be a Direct Digital Synthesis (DDS) signal generator. The DDS signal generator can use a large-scale fully parallel computing array as the execution unit, a large-capacity 32-bit bandwidth First Input First Output (FIFO) array as the pre-computation unit, and a high-frequency low-temperature drift oscillation array as the trigger unit. The trigger unit uses a 100 MHz frequency to trigger the execution unit to output the high-frequency traveling wave waveform data of the pre-computation unit, thereby completing the DDS signal generation.

[0051] In some embodiments, the amplitude controller 1022 can be used to control the amplitude of the traveling wave waveform data generated by the signal generator to obtain a first analog signal.

[0052] In some embodiments, the amplitude controller 1022 may be composed of a 16-bit multiplication digital-to-analog converter (DAC), which can control the amplitude of the signal emitted by the DDS, and the adjustment accuracy can reach more than 0.01%.

[0053] In some embodiments, the operational amplifier mixer 1023 can be used to perform negative feedback operation based on a first analog signal and a sampled signal output by a current detector, and output a second analog signal.

[0054] In some embodiments, the operational amplifier mixer 1024 may be an adder composed of a high-frequency, high-precision operational amplifier with a gain bandwidth of 100MHz and a voltage conversion rate greater than 1000 volts / microsecond (V / uS). It receives an analog high-frequency signal (first analog signal) transmitted from the amplitude controller 1022, adds the analog high-frequency signal to the sampling signal of the current detector 1025 and performs a negative feedback operation. The resulting second analog signal is sent to the high-frequency power amplifier 1024. The operational amplifier mixer 1024 can process signals with a -3dB frequency of up to 20MHz.

[0055] In some embodiments, the high-frequency amplifier 1024 can be used to amplify the second analog signal to obtain a third analog signal.

[0056] In some embodiments, the high-frequency power amplifier 1024 may be composed of a high-frequency, high-precision operational amplifier and a push-pull high-speed transistor pair, which amplifies the second analog signal transmitted from the operational amplifier mixer 1023, and the power bandwidth can reach 1.2MHz in the range of -3dB.

[0057] In some embodiments, the current detector 1025 can be used to detect the current of the third analog signal and output the third analog signal to the traveling wave positioning sensor.

[0058] In some embodiments, the current detector 1025 may be a non-inductive platinum resistance thermometer. When the third analog signal output by the high-frequency power amplifier 1024 is a current signal, the current detector 1025 accurately detects the high-frequency large current (third analog signal) output by the high-frequency power amplifier 1024 to determine whether the high-frequency large current is too large.

[0059] In some embodiments, the current detector 1025 may also send a third analog signal, which has been confirmed as qualified by current detection, to the traveling wave positioning sensor for detection of the traveling wave positioning sensor.

[0060] It is understandable that by generating traveling wave waveform data through a signal generator, controlling the amplitude of the traveling wave waveform data through an amplitude controller, filtering the amplitude-controlled analog signal through an operational amplifier mixer, amplifying the filtered analog signal through a high-frequency amplifier, and detecting the current in the amplified analog signal through a current detector, the accuracy and stability of the first electrical signal finally output by the signal source generator can be improved.

[0061] In some embodiments of this application, as shown in FIG2, the high-frequency amplifier 1024 and the current detector 1025 each include multiple ones. One high-frequency amplifier 1024 and one current detector 1025 constitute a series circuit, and the series circuits are connected in parallel.

[0062] It is understandable that by using a structure in which each high-frequency amplifier 1024 and its corresponding current detector 1025 are connected in series and then in parallel, the heat dissipation of the signal source generator during operation can be dispersed, and the distributed inductance can be reduced.

[0063] In some embodiments of this application, the current detector 1025 is also used to output an overcurrent protection signal to the high-frequency amplifier 1024 to protect the overcurrent signal when it is determined that an overcurrent signal exists in the third analog signal.

[0064] In some embodiments, after the current detector 1025 detects the current in the third analog signal, if it determines that there is an overcurrent signal in the third analog signal, it can output an overcurrent signal to the high-frequency power amplifier 1024 to protect the power device, and amplify the sampled signal and feed it back to the operational amplifier mixer 1023.

[0065] Understandably, by using a current detector to detect the current in the third analog signal output by the high-frequency amplifier, it can determine whether there is an overcurrent signal in the third analog signal, and if an overcurrent signal is found, it can send an overcurrent protection signal to the high-frequency amplifier. This can protect the power devices of the signal source generator and ensure the accuracy of the current in the final output third analog signal.

[0066] In some embodiments of this application, the signal recording device 103 includes a first processing module 1031, a second processing module 1032, a programmable logic module 1033, and a storage module 1034.

[0067] In some embodiments, the first processing module 1031 can be used to determine the sampling frequency for the second electrical signal. The first processing module 1031 can be a central processing unit (CPU), and the sampling frequency of the second electrical signal can be the frequency of the output second electrical signal of the traveling wave positioning sensor. The first processing module 1031 can analyze one cycle of the second electrical signal to determine the sampling frequency.

[0068] In some embodiments, the programmable logic module 1033 can be used to sample the second electrical signal according to the sampling frequency and transmit the sampled signal to the storage module 1034 for storage.

[0069] In some embodiments, the programmable logic module 1033 may be a field programmable gate array (FPGA), which can sample the second electrical signal, and the storage module 1034 may be a static random-access memory (SRAM), which stores the sampled signal in the SRAM.

[0070] In some embodiments, the second processing module 1032 may be used to obtain the sampled signal from the storage module 1034 and send the sampled signal to the industrial control computer 101.

[0071] In some embodiments, the second processing module 1032 may also be a CPU unit. The second processing module 1032 and the first processing module 1031 may be different CPU units. The second processing module 1032 may obtain the sampled signal from the storage module 1034 as needed (e.g., the industrial computer 101 sends a signal acquisition request to the signal acquisition device) and feed the sampled signal back to the industrial computer 101.

[0072] In some embodiments, the signal recording device 103 can be a high-frequency waveform recorder. For example, as shown in FIG3, which is a structural schematic diagram of a high-frequency waveform recorder provided in this application, the high-frequency waveform recorder 300 includes a computing CPU 301, an FPGA 302, a management CPU 303, an SRAM 304, a dual gigabit network card 305, and a communication bus 306. The electrical measurement part mainly consists of an 8-channel synchronous analog-to-digital (AD) converter 307 and voltage and current analog channels.

[0073] In waveform recording mode, the CPU 301 of the high-frequency waveform recorder 300 takes one cycle of sampled data, calculates various data, and determines the sampling frequency. The FPGA 302 continuously sends the AD sampled data into the SRAM 304 in real time. The management CPU 303 periodically acquires waveform data from the SRAM 304 and sends it to the server via the dual gigabit network card 305 using the User Datagram Protocol (UDP) through the Reduced Media Independent Interface (RMII). The maximum sampling rate is 1000 kilo samples per second (Ksps). The FPGA and AD use an 8-channel Serial Peripheral Interface (SPI) to send the acquired AD data into the SRAM 304 (2 megabytes / M bytes), without the need for intervention from the calculation CPU 301. Each cycle contains 8192 bytes * 8 = 131070 bytes; SRAM 304 can cache 16 cycles, or 0.32 seconds of data. The management CPU 303 uses an External Bus Interface (EBI) interface and an Interrupt Request (IRQ) to retrieve waveform data from SRAM 304 at 0.2-second intervals, taking approximately 5 milliseconds to retrieve 0.2 seconds of waveform data. The management CPU 304 sends the data to the server (industrial computer 101) via UDP protocol, with a data stream of approximately 65 megabits per second (bits / s). The utilization rate of the management CPU 303 is less than 50% during 100-second waveform recording.

[0074] It is understandable that by determining the sampling frequency of the second electrical signal through the first processing module, the programmable logic module samples the second electrical signal according to the sampling frequency and transmits the sampled signal to the storage module for storage. The second processing module retrieves the sampled signal from the storage module and sends the sampled signal to the industrial control computer. This can achieve accurate recording of the second electrical signal and reduce the transmission error of the second electrical signal output by the traveling wave positioning sensor.

[0075] In some embodiments of this application, both the signal source generating device 102 and the signal receiving device 102 include multiple devices; each signal source generating device 102 corresponds to one signal receiving device 103, and each signal source generating device 102 and the corresponding signal receiving device 103 are set on the same test equipment, and different test equipment are connected to different traveling wave positioning sensors; each test equipment and the industrial control computer 101 are established with a communication connection.

[0076] In some embodiments, the industrial control computer 101 can establish a communication connection with each test device through Internet Protocol (IP) address, port number and other information to control the signal source generator 102 in each test device to generate a first electrical signal. In addition, after the signal receiving device 103 in the test device obtains the second electrical signal output by the traveling wave positioning sensor, it can send the second electrical signal to the industrial control computer 101. The industrial control computer 101 can determine the corresponding traveling wave positioning sensor under test according to the IP address, port number and other information of the test screen that sent the second electrical signal, thereby obtaining the detection result of the corresponding traveling wave positioning sensor.

[0077] For example, as shown in Figure 4, in order to realize multi-station testing, the test control part such as the industrial control computer 101 can be set in the control panel 401, and the signal source generator 102 and the signal receiving device 103 can be set in the test panel 402. The control panel 401 and the test panel 402 are connected through the communication bus 403. The signal source generator 102 in multiple test panels 402 can be controlled to output the detection analog quantity (first electrical signal) through information such as IP address and port number. The signal receiving device 103 in the test panel 402 sends the measured data (second electrical signal) to the control panel 401 through the communication bus 403. The control panel 401 locates the test panel 402 according to the IP address, port number and other information of the received signal receiving device 203, and compares and analyzes the test data to realize the simultaneous testing of multiple test panels 402. There is no upper limit to the number of test panels 402, and they can be expanded arbitrarily according to needs to achieve the purpose of large-scale testing of the power distribution network traveling wave positioning sensor 404.

[0078] This application provides a method for detecting a traveling wave positioning sensor. This method is applied to the traveling wave positioning sensor detection system provided in this application, as shown in Figure 5. The method includes:

[0079] S501, The signal source generating device generates a first electrical signal with a signal frequency greater than a first frequency threshold and sends the first electrical signal to the traveling wave positioning sensor.

[0080] In some embodiments, the first frequency threshold can be the frequency value of a voltage signal, current signal, etc., and the first frequency threshold can be 500 kHz, 1000 kHz, etc.; the first frequency threshold can be determined based on the frequency parameters of the traveling wave positioning sensor under test; the first frequency threshold can be set by test software installed on the industrial control computer 101, and the first electrical signal can be a high-frequency electrical signal by the limitation of the first frequency threshold.

[0081] In some embodiments, the first electrical signal can be a high-frequency analog signal, such as a high-frequency analog voltage signal or a high-frequency analog current signal; the first electrical signal can be an alternating current signal, such as an alternating voltage signal or an alternating current signal.

[0082] In some embodiments, the signal source generating device 102 can generate a first electrical signal based on the information such as the frequency and amplitude of the first electrical signal sent by the industrial control computer 101 after receiving such information, and send the generated first electrical signal to the traveling wave positioning sensor connected thereto for detection of the traveling wave positioning sensor.

[0083] S502, The signal acquisition device acquires the second electrical signal after the traveling wave positioning sensor transforms and processes the first electrical signal, and sends the second electrical signal to the industrial control computer.

[0084] In some embodiments, the traveling wave positioning sensor can perform amplitude transformation on the input first electrical signal. For example, when the first electrical signal is an alternating current signal, the amplitude of the first electrical signal can be converted into the amplitude of the second electrical signal through the CT ratio, and the amplitude of the second electrical signal is smaller than the amplitude of the first electrical signal.

[0085] In some embodiments, the signal acquisition device 103 and the traveling wave positioning sensor are electrically connected. Therefore, the second electrical signal obtained by the traveling wave positioning sensor based on the first electrical signal can be acquired and the acquired second electrical signal can be sent to the industrial control computer.

[0086] In some embodiments, the signal acquisition device 103 can acquire multiple discrete signal values ​​based on the frequency of the traveling wave positioning sensor, and then perform curve fitting on the multiple discrete signals to obtain the waveform corresponding to the second electrical signal, thereby realizing the restoration of the second electrical signal.

[0087] S503, the industrial control computer acquires the second electrical signal and determines the detection result of the traveling wave positioning sensor based on the second electrical signal.

[0088] In some embodiments, the detection result of the traveling wave positioning sensor may include whether the sampling frequency of the traveling wave positioning sensor is accurate. For example, whether the actual sampling frequency of the traveling wave positioning sensor is consistent with the sampling frequency specified in the factory parameters of the traveling wave positioning sensor. The detection result of the traveling wave positioning sensor may also include the sampling accuracy of the traveling wave positioning sensor.

[0089] In some embodiments, the industrial control computer 101 can analyze and process the second electrical signal sent by the signal recording device 103, such as calibrating the sampling frequency of the traveling wave positioning sensor or determining the sampling accuracy of the traveling wave positioning sensor, thereby obtaining the detection result of the traveling wave positioning sensor.

[0090] In this embodiment, a signal source generating device generates a first electrical signal with a frequency greater than a first frequency threshold and sends the first electrical signal to a traveling wave positioning sensor. A signal receiving device collects a second electrical signal from the traveling wave positioning sensor after processing the first electrical signal and sends the second electrical signal to an industrial control computer. The amplitude of the second electrical signal is less than the amplitude of the first electrical signal. The industrial control computer acquires the second electrical signal and determines the detection result of the traveling wave positioning sensor based on the second electrical signal. Thus, by generating a first electrical signal with a frequency greater than a preset frequency threshold, collecting a second electrical signal from the traveling wave positioning sensor after processing the first electrical signal, and determining the detection result of the traveling wave positioning sensor based on the second electrical signal by the industrial control computer, the accuracy of the traveling wave positioning sensor can be traced and verified. Furthermore, the detection result can help improve the fault location capability of the traveling wave positioning sensor.

[0091] In some embodiments of this application, before the signal source generating device 102 generates a first electrical signal with a signal frequency greater than a first frequency threshold and sends the first electrical signal to the traveling wave positioning sensor, the industrial control computer 101 can also acquire parameter information of the traveling wave positioning sensor; based on the parameter information, determine test information for the traveling wave positioning sensor.

[0092] In some embodiments, the parameter information of the traveling wave positioning sensor may include information such as the frequency and CT ratio of the traveling wave positioning sensor. Different traveling wave positioning sensors may have different frequencies and CT ratios, so the test information determined for different traveling wave positioning sensors may also be different.

[0093] In some embodiments, the test information includes at least the amplitude of the first electrical signal, the fault signal threshold, and the signal error threshold. Based on the parameter information of the traveling wave positioning sensor, the amplitude of the first electrical signal, the fault signal threshold, and the signal error threshold can be edited or set using the test software of the industrial control computer 101.

[0094] Understandably, based on the parameter information of the traveling wave positioning sensor, it is possible to personalize the test information of the traveling wave positioning sensor, thereby meeting the different test requirements of different traveling wave positioning sensors.

[0095] In some embodiments of this application, the detection result includes the sampling accuracy of the traveling wave positioning sensor. Based on this, in the process of determining the detection result of the traveling wave positioning sensor based on the second electrical signal, the industrial control computer 101 can convert the second electrical signal to obtain a third electrical signal. The industrial control computer 101 converts the second electrical signal to obtain the third electrical signal. Based on the fault signal threshold, the target electrical signal in the third electrical signal is determined, and the amplitude of the target electrical signal is obtained. Based on the absolute value of the difference between the amplitude of the target electrical signal and the amplitude of the first electrical signal, and the signal error threshold, the sampling accuracy of the traveling wave positioning sensor is determined.

[0096] In some embodiments, the industrial computer 101 can convert the amplitude of the second electrical signal to obtain a third electrical signal, wherein the amplitude of the third electrical signal is greater than the amplitude of the second electrical signal.

[0097] In some embodiments, the fault signal threshold can be the minimum value of the fault signal amplitude. The fault signal, i.e. the target electrical signal, can be determined from the third electrical signal by the fault signal threshold. For example, when the third electrical signal is a current signal, the fault signal threshold can be 4A, and the target electrical signal can be an electrical signal with an amplitude greater than 4A in the third electrical signal.

[0098] In some embodiments, the signal error threshold may be the maximum permissible error between the amplitude of the signal acquired by the traveling wave positioning sensor and the amplitude of the test signal generated by the signal source generator 102. The amplitude of the first electrical signal may be the true amplitude of the first electrical signal determined by the test software of the industrial control computer 101. By calculating the absolute value of the difference between the amplitude of the target electrical signal and the amplitude of the first electrical signal, the measurement error of the traveling wave positioning sensor can be determined. Furthermore, by comparing the absolute value of the difference with the signal error threshold, the sampling accuracy of the traveling wave positioning sensor can be determined.

[0099] It is understandable that by converting the second electrical signal through an industrial control computer to obtain a third electrical signal, the target electrical signal can be determined from the third electrical signal based on the fault signal threshold, and the sampling accuracy of the traveling wave positioning sensor under test can be accurately determined based on the absolute value of the difference between the amplitude of the target electrical signal and the amplitude of the first electrical signal, as well as the signal error threshold.

[0100] The implementation process of the application embodiments in practical application scenarios is described below.

[0101] This application provides a distribution network traveling wave location sensor detection system, as shown in Figure 6. The distribution network traveling wave location sensor detection system 600 consists of test software 601, a high-frequency signal source 602 (equivalent to a "signal source generating device" in other embodiments), and a high-frequency waveform recorder 603 (equivalent to a "signal receiving device" in other embodiments). It adopts a closed-loop detection architecture: test cases are edited on the test software 601, and the high-frequency signal source 602 is controlled to output a primary high-frequency signal (equivalent to a "first electrical signal" in other embodiments). The distribution network traveling wave location sensor 604 under test collects this signal. The high-frequency waveform recorder 603 records the secondary high-frequency signal (equivalent to a "second electrical signal" in other embodiments) after the primary high-frequency signal collected by the distribution network traveling wave location sensor 604 under test, forming a waveform recording file in the standard power system transient data exchange format (Comtrade) and sending it to the test software 601. The test software 601 compares and analyzes the detection data and generates a detection report. The 604 traveling wave positioning sensor for power distribution networks can be used to detect the sampling accuracy and sampling rate of power frequency or traveling wave current.

[0102] The test software 601 is installed on the industrial control computer 101. The test software 601 can perform electromagnetic transient program (EMTP) simulation of fault current traveling wave and waveform inversion of recorded data on site, control the high-frequency signal source 602 to output the corresponding current signal, and accept the Comtrade format waveform data file recorded by the high-frequency waveform recorder 603, automatically compare it with the standard output data, and generate an electronic test report.

[0103] In some embodiments, the high-frequency signal source 602 is controlled by the test software 601 to output the analog power frequency or high-frequency current required for detection. The high-frequency signal source 602 is a controllable constant current source with an output frequency range of DC to 1000kHz; it consists of a DDS signal generator, an amplitude controller, an operational amplifier mixer, several intermediate frequency power amplifiers, and a current detector. Its core feature is the parallel output of multiple high-power high-frequency power amplifiers and current detectors, which disperses heat dissipation during operation and reduces distributed inductance.

[0104] In some embodiments, the high-frequency signal source 602 may include 20 high-frequency high-power amplifiers, capable of outputting a maximum power of 200A (4000VA) at a maximum frequency of 1000kHz, with a port voltage of 20V. The structure of the high-frequency signal source 602 is shown in Figure 2: the signal generator 1021 uses advanced DDS digital signal generation technology to maintain accurate and stable waveform signals. The amplitude controller 1022 employs a multi-bit serial multiplier DAC to adapt to the amplitude control of high-frequency signals; the operational amplifier mixer 1023 consists of a voltage amplifier and a feedback adder, ensuring the accuracy of the final output current; the high-frequency power amplifier 1024 consists of multiple Class A power amplifiers with a maximum output of 10A; the current detector 1025 consists of multiple high-precision sampling resistors and high-speed operational amplifiers, providing feedback signals to the operational amplifier mixer 1024.

[0105] In some embodiments, the structure of the high-frequency waveform recorder 603 is shown in Figure 3. The high-frequency waveform recorder 603 includes a measurement mode and a waveform recording mode. The flow chart of the measurement mode is shown in Figure 7.

[0106] S701. Determine whether the CPU has completed the calculation of the sampled data for one cycle.

[0107] If yes, proceed to steps S702 to S703; otherwise, proceed to step S704.

[0108] The S702 and FPGA send the calculated data to the management CPU.

[0109] S703 manages the CPU to send the calculated data to the test software.

[0110] S704. The CPU acquires AD data to perform calculations on the sampled data of one cycle.

[0111] In some embodiments, the sampling rate of the electrical measurement section is 12.8Ksps. The FPGA 302 tracks and samples the data in real time according to the actual frequency of the line, and the sampled data is sent to the SRAM 304. The calculation CPU 301 takes the sampled data once per cycle to calculate various data. The calculated data is then averaged once per second and sent to the management CPU 303 through the parallel serial port of the FPGA 302.

[0112] In some embodiments, the processing flow of the recording mode of the high-frequency waveform recorder 603 is shown in Figure 8:

[0113] S801: Obtain the data calculated by the CPU from the sampled data of one cycle.

[0114] In some embodiments, the computing CPU 301 of the high-frequency waveform recorder 603 can take one cycle of sampled data to calculate various data and determine the sampling frequency before recording.

[0115] The S802 and FPGA store the calculated sampled data in SRAM.

[0116] In some embodiments, FPGA 302 can send AD sampling data into SRAM 304 in real time and without interruption.

[0117] S803 manages the CPU to obtain waveform data from SRAM and sends the waveform data to the test software.

[0118] In some embodiments, the management CPU 301 periodically acquires waveform data from the SRAM 304 and sends it to the test software 601 via the UDP protocol from the dual gigabit network card 305.

[0119] This application provides an automatic closed-loop testing method for a traveling wave positioning sensor in a power distribution network, as shown in Figure 9. The method includes:

[0120] S901. Input the parameter information of the traveling wave positioning sensor of the power distribution network under test.

[0121] In some embodiments, the parameter information of the traveling wave positioning sensor 604 of the distribution network under test includes information such as the manufacturer, model, date, and CT ratio of the traveling wave positioning sensor 604 of the distribution network under test.

[0122] S902. Edit test cases using testing software.

[0123] In some embodiments, test cases can be edited on the test software 601, including editing of power frequency measurement data, thresholds and traveling wave current waveforms, thresholds, etc.

[0124] S903, high-frequency signal source outputs a high-frequency signal.

[0125] In some embodiments, the high-frequency signal source 602 can be controlled to output a high-frequency signal (test analog quantity) based on the completed test case.

[0126] S904, high-frequency waveform recorder to collect measured data.

[0127] In some embodiments, the high-frequency waveform recorder 601 can acquire the secondary high-frequency signal (test analog quantity) output by the primary high-frequency signal acquired by the traveling wave positioning sensor 604 of the distribution network under test, and send the secondary high-frequency signal to the test software 601.

[0128] S905: The testing software performs fitting analysis based on the measured data to obtain the fitting analysis results.

[0129] In some embodiments, the test software 601 can convert the secondary high-frequency signal into a primary quantity according to information such as the set CT ratio, etc., and perform data fitting analysis to obtain the fitting analysis result.

[0130] S906. Generate a test report based on the fitting analysis result.

[0131] In some embodiments, the test software 601 can compare the fitting analysis result with the set threshold. If it is within the threshold range, it is judged as qualified; otherwise, it is judged as unqualified. Among them, when the threshold is set such that the power frequency or traveling wave current ≤ 10A, the measurement error of the traveling wave current amplitude should be ≤ ±0.2A; when the power frequency or traveling wave current > 10A, the measurement error of the traveling wave current amplitude should be ≤ ±5%; the power frequency current sampling rate ≥ 12.8kHZ; the traveling wave current sampling rate ≥ 500kHZ. According to the comparison result, fill in the test report template to generate an electronic test report.

[0132] In some embodiments, in order to implement the automatic closed-loop detection of the distribution network traveling wave positioning sensor 604, the fitting analysis of the secondary high-frequency signal collected by the measured distribution network traveling wave positioning sensor 604 is an important part. The fitting analysis process of the secondary high-frequency signal is shown in Figure 10 and includes:

[0133] S11. Perform filtering processing on the secondary high-frequency signal collected by the distribution network traveling wave positioning sensor to obtain the filtered high-frequency signal.

[0134] In some embodiments, the noise signal outside the high-frequency signal in the secondary high-frequency signal can be removed, such as the medium and low-frequency signals within 50kHz, and the high-frequency signals between 50kHz and 1000kHz are retained.

[0135] S12. Synthesize digital feature quantities based on the filtered high-frequency signal.

[0136] In some embodiments, the digital feature quantities can be synthesized based on the 2M digital fitting technology for the filtered high-frequency signal, including identifying the time-domain signal and frequency-domain signal of the wavefront.

[0137] S13. Compare the synthesized digital feature quantities with the true digital feature quantities to obtain a comparison result.

[0138] In some embodiments, the true digital feature quantities can include the true time-domain signal and true frequency-domain signal of the wavefront. The time-domain signal of the wavefront obtained by fitting analysis can be compared with the true time-domain signal of the wavefront, and the frequency-domain signal of the wavefront obtained by fitting analysis can be compared with the true frequency-domain signal of the wavefront.

[0139] S14. Compare the comparison result with the set threshold to obtain a detection conclusion.

[0140] In some embodiments, setting a threshold may include a time-domain signal error threshold and a frequency-domain signal error threshold. The comparison result may include a first difference between the wavefront time-domain signal and the true wavefront time-domain signal, and a second difference between the wavefront frequency-domain signal and the true wavefront frequency-domain signal. By comparing the first difference with the time-domain signal error threshold and the second difference with the frequency-domain signal error threshold, it can be determined whether the frequency of the power distribution network traveling wave positioning sensor 604 is accurate.

[0141] It is understood that the distribution network traveling wave positioning sensor detection method and system provided in this application comprehensively considers factors such as the wide bandwidth and high sampling rate of the distribution network traveling wave positioning sensor, designs an effective high-frequency signal source, and establishes a multi-station distribution network traveling wave positioning sensor detection system. This can realize the traceability and verification of the distribution network traveling wave positioning sensor, improve the accuracy of distribution network traveling wave positioning, and ensure power supply reliability.

[0142] It should be noted that the description of the traveling wave positioning sensor detection method in this application is similar to the description of the traveling wave positioning sensor detection system embodiment described above, and has similar beneficial effects to the system embodiment; therefore, it will not be repeated. For technical details not disclosed in this embodiment, please refer to the description of the method embodiment in this application for understanding.

[0143] It should be noted that, in this document, the term "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising at least one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0144] In the several embodiments provided in this application, it should be understood that the disclosed systems and methods can be implemented in other ways. The system embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, and can be electrical, mechanical, or other forms.

[0145] The above are merely embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A traveling wave positioning sensor detection system, characterized in that, It includes an industrial control computer, a signal source generator, and a signal receiving device, wherein the signal source generator and the signal receiving device are respectively connected to the industrial control computer; The signal source generating device is used to generate a first electrical signal with a signal frequency greater than a first frequency threshold, and send the first electrical signal to the traveling wave positioning sensor; The signal acquisition device is used to acquire the second electrical signal after the traveling wave positioning sensor has transformed the first electrical signal, and to send the second electrical signal to the industrial control computer; the amplitude of the second electrical signal is less than the amplitude of the first electrical signal. The industrial control computer is used to acquire the second electrical signal and determine the detection result of the traveling wave positioning sensor based on the second electrical signal.

2. The traveling wave positioning sensor detection system according to claim 1, characterized in that, The industrial control computer is also used to determine the information of the first electrical signal according to the parameters of the traveling wave positioning sensor, and send the information of the first electrical signal to the signal source generating device, so that the signal source generating device generates the first electrical signal based on the information of the first electrical signal.

3. The traveling wave positioning sensor detection system according to claim 1, characterized in that, The industrial control computer is also used to determine a fault signal threshold and a signal error threshold, so as to analyze and process the second electrical signal based on the fault signal threshold and the signal error threshold, and determine the detection result of the traveling wave positioning sensor.

4. The traveling wave positioning sensor detection system according to claim 1, characterized in that, The signal source generating device includes a signal generator, an amplitude controller, an operational amplifier mixer, a high-frequency amplifier, and a current detector connected in sequence. The signal generator is used to generate traveling wave waveform data; The amplitude controller is used to control the amplitude of the traveling wave waveform data to obtain a first analog signal; The operational amplifier mixer is used to perform negative feedback operation based on the first analog signal and the sampled signal output by the current detector, and output a second analog signal. The high-frequency amplifier is used to amplify the second analog signal to obtain a third analog signal; The current detector is used to detect the current of the third analog signal and output the third analog signal to the traveling wave positioning sensor.

5. The traveling wave positioning sensor detection system according to claim 4, characterized in that, The current detector is also used to output an overcurrent protection signal to the high-frequency amplifier to protect the overcurrent signal when it is determined that an overcurrent signal exists in the third analog signal.

6. The traveling wave positioning sensor detection system according to claim 4, characterized in that, The high-frequency amplifier and the current detector each include multiple units. One high-frequency amplifier and one current detector form a series circuit, and the various series circuits are connected in parallel.

7. The traveling wave positioning sensor detection system according to any one of claims 1 to 6, characterized in that, The signal recording device includes a first processing module, a second processing module, a programmable logic module, and a storage module; The first processing module is used to determine the sampling frequency for the second electrical signal; The programmable logic module is used to sample the second electrical signal according to the sampling frequency and transmit the sampled signal to the storage module for storage. The second processing module is used to obtain the sampled signal from the storage module and send the sampled signal to the industrial control computer.

8. The traveling wave positioning sensor detection system according to claim 7, characterized in that, Both the signal source generating device and the signal receiving device include multiple components; Each signal source generating device corresponds to a signal receiving device. Each signal source generating device and its corresponding signal receiving device are set up on the same test equipment. Different test equipment are connected to different traveling wave positioning sensors. Each test equipment and the industrial control computer are connected to each other.

9. A method for detecting a traveling wave positioning sensor, applied to the traveling wave positioning sensor detection system according to any one of claims 1 to 8, characterized in that, include: The signal source generating device generates a first electrical signal with a signal frequency greater than a first frequency threshold, and sends the first electrical signal to the traveling wave positioning sensor; The signal acquisition device collects the second electrical signal obtained by the traveling wave positioning sensor after transforming the first electrical signal, and sends the second electrical signal to the industrial control computer; the amplitude of the second electrical signal is less than the amplitude of the first electrical signal. The industrial control computer acquires the second electrical signal and determines the detection result of the traveling wave positioning sensor based on the second electrical signal.

10. The traveling wave positioning sensor detection method according to claim 9, characterized in that, The method further includes: The industrial control computer acquires the parameter information of the traveling wave positioning sensor; Based on the parameter information, test information for the traveling wave positioning sensor is determined; the test information includes at least the amplitude of the first electrical signal, the fault signal threshold, and the signal error threshold.

11. The traveling wave positioning sensor detection method according to claim 10, characterized in that, The detection results include the sampling accuracy of the wave positioning sensor; Determining the detection result of the traveling wave positioning sensor based on the second electrical signal includes: The industrial control computer converts the second electrical signal to obtain a third electrical signal; the amplitude of the third electrical signal is greater than the amplitude of the second electrical signal. The target electrical signal in the third electrical signal is determined based on the fault signal threshold, and the amplitude of the target electrical signal is obtained. The sampling accuracy of the traveling wave positioning sensor is determined based on the absolute value of the difference between the amplitude of the target electrical signal and the amplitude of the first electrical signal, and the signal error threshold.

Images