High-voltage circuit breaker opening and closing coil current test system

Abstract

The invention relates to a high-voltage circuit breaker opening and closing coil current test system, which comprises a signal acquisition module, a data processing module, a data storage module, a defect diagnosis module and a man-machine interaction module, and is characterized in that the signal acquisition module, the data processing module, the data storage module and the defect diagnosis module are connected in sequence; the data storage module and the defect diagnosis module are both connected to the man-machine interaction module. According to the invention, in hardware, the system has higher sampling rate and resolution, longer waveform recording duration, autonomous setting of trigger level and self-defined filtering functions. In software, waveform operation, waveform comparison analysis, correlation coefficient calculation and auxiliary function judgment can be carried out. In the aspects of portability and expansibility, a handheld portable design is adopted, and meanwhile, different acquisition cards can be replaced according to needs. The circuit breaker opening and closing coil current test system has excellent applicability, precision, stability, portability and data processing capability, and has a wide application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of high-voltage circuit breaker coil current testing, and in particular relates to a high-voltage circuit breaker opening and closing coil current testing system. Background Art

[0002] Under the general background of "carbon peak and carbon neutrality", the power industry is undergoing unprecedented development and great changes. As one of the most core equipment in the power system, switch equipment plays a role of control and protection. The quality of the equipment status directly affects the safe and stable operation of itself and even the regional power grid. Therefore, it is necessary to conduct regular tests and evaluations on the insulation status and mechanical properties of the circuit breaker. At present, the diagnostic test methods for switch equipment are very limited and are limited to conventional routine test items, including mechanical action characteristic tests, loop resistance tests, and direct resistance tests of opening and closing coils. When encountering GIS equipment without grounding block lead-out, the test methods are even more limited, which is not conducive to the implementation of diagnostic tests.

[0003] During the operation of the circuit breaker, the corresponding opening and closing operation coil current waveforms can reflect the status of the circuit breaker operating mechanism and control circuit. In addition, the coil current of each circuit breaker has certain fingerprint characteristics during the operation process, which is of great significance for the mechanical fault judgment of the circuit breaker operating mechanism and the diagnosis and identification of potential mechanical faults.

[0004] The circuit breaker opening and closing coil current test system can be widely used in the fault diagnosis process of switch equipment of various voltage levels and models, helping maintenance testers to quickly determine the fault location and improve maintenance efficiency. At present, the existing instruments on the market have the following problems: First, the hardware performance is weak, the caliper is not stable enough, the sampling rate is not high, the trigger level cannot be set, the recording length is limited, and there is no filtering function. Second, the waveform analysis function is limited, and only waveform comparison and analysis can be performed manually, without waveform calculation and auxiliary judgment functions. Third, the portability and scalability are poor, and an external power supply is required. Fourth, the communication performance between software and hardware is poor. When the caliper is adjusted to change the wiring, the software system will be disconnected, and the host power supply needs to be restarted frequently. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art, provide a high-voltage circuit breaker opening and closing coil current test system, and provide a set of hardware and software with more powerful performance, while taking into account portability and scalability. In terms of hardware, it has a higher sampling rate and resolution, a longer waveform recording time, and can independently set the trigger level and customize the filtering function; in terms of software, it can perform waveform calculations, waveform comparison analysis, correlation coefficient calculations, and auxiliary function judgments. In terms of portability and scalability, it adopts a handheld portable design, and different acquisition cards can be replaced as needed. The circuit breaker opening and closing coil current test system has excellent applicability, accuracy, stability, portability, and data processing capabilities, and has broad application prospects.

[0006] The present invention solves the technical problem by the following technical solutions:

[0007] A high-voltage circuit breaker opening and closing coil current test system, comprising a signal acquisition module, a data processing module, a data storage module, a defect diagnosis module and a human-computer interaction module, wherein the signal acquisition module, the data processing module, the data storage module and the defect diagnosis module are connected in sequence, and the data storage module and the defect diagnosis module are both connected to the human-computer interaction module;

[0008] The signal acquisition module is located on the current sampling clamp, detects the opening and closing coil current of the circuit breaker through the current sensor, and inputs the electrical signal into the data processing module after analog filtering and A / D conversion;

[0009] The data processing module performs filtering processing on the original current digital signal;

[0010] The data storage module receives and stores the circuit breaker opening and closing coil current processed by the data processing module, and stores the historical data of the circuit breaker opening and closing coil current; the data in the data storage module is called by the human-computer interaction module on the one hand, and the current coil opening and closing current or historical current data of the current test is updated in real time on the display; on the other hand, it is called and input into the defect diagnosis module, and the defect diagnosis module calculates the Pearson correlation coefficient of the opening and closing coil current, and determines the current state of the high-voltage circuit breaker based on the current and historical Pearson correlation coefficients of the coil current, and predicts the development trend of the future circuit breaker operation state. The defect diagnosis results and trend development of the defect diagnosis module will be displayed in the human-computer interaction module.

[0011] Moreover, the signal acquisition module is composed of a Hall current sensor, an analog filter and an A / D conversion module, and collects the current of the opening and closing coil after the circuit breaker is actuated. The pre-filter performs preliminary noise reduction on the signal, and then inputs it into the data processing module through analog-to-digital conversion. At the same time, the module can independently set the trigger pulse and has a sampling locking function. When the sampling clamp is disconnected, the current signal sampling and filtering are no longer performed.

[0012] Moreover, the data processing module is a secondary precision filter of the digital filter, which performs Kalman filtering on the rough digital signal of the signal acquisition module to obtain a smooth current signal curve, which is stored in the data storage module and input into the defect diagnosis module to determine the operating status of the circuit breaker.

[0013] Moreover, the data storage module is a data receiving terminal and a disk. The data storage module can be replaced by plugging and unplugging a memory card, and the data transmission module can be updated by Bluetooth and wired transmission. On the one hand, it stores the historical data of the circuit breaker opening and closing coil current, and on the other hand, it receives the digital signal data of the circuit breaker opening and closing coil current sent by the signal acquisition module and the data processing module, and forms a new historical data packet in the disk. At the same time, it has a read-write port for exchanging data / commands with the fault diagnosis module and the human-computer interaction module.

[0014] Moreover, the defect diagnosis module receives the currently collected and filtered opening and closing coil current data, extracts the historical data of the circuit breaker from the data storage module, and uses the segmented Pearson correlation coefficient to compare the new current data with multiple historical data to obtain the operating status and change trend of the circuit breaker. At the same time, it has a read-write port for data / command exchange with the human-computer interaction module;

[0015] The specific process of the segmented Pearson correlation coefficient is as follows: first, determine the inflection point of the current waveform of the circuit breaker opening and closing coil, and segment the current waveform according to the inflection point into four or five segments; then, calculate the Pearson correlation coefficient on each monotonous curve segment; when the number of sampling points of the new current data and the historical data in the segment is different, the length principle is adopted, and the short data segment is expanded by linear interpolation. When the dimensions of the two data segments are consistent, the Pearson correlation coefficient of the two is calculated, which is the Pearson correlation coefficient of the segment; finally, judge the operating status of the circuit breaker. When each segment shows a strong correlation, it indicates that the circuit breaker is in good condition. When the correlation of a certain segment is weak, there is reason to suspect that the circuit breaker is in poor condition and needs to be further diagnosed in combination with other test items.

[0016] Moreover, the human-computer interaction module has a read-write port for exchanging data / commands with the data storage module and the defect diagnosis module respectively. The currently measured or historical circuit breaker opening and closing coil current waveform can be called and displayed from the data storage module, and the good or bad state of the opening and closing coil current under this measurement can be read from the defect diagnosis module and displayed on the screen for on-site maintenance personnel to review; before performing the circuit breaker test, the maintenance personnel can update the corresponding circuit breaker historical data in the data storage module through the human-computer interaction module, and the technicians can also adjust and set the programs and parameters of the data processing module and the defect diagnosis module through the human-computer interaction module.

[0017] The advantages and beneficial effects of the present invention are:

[0018] 1. The present invention provides a set of opening and closing coil current test system with powerful software and hardware performance, portability and scalability, which can complete the accurate sampling and accurate judgment of the opening and closing coil current of the high-voltage circuit breaker in a very short time, ensuring that the test operation and maintenance personnel can accurately grasp the operating status of the switch equipment, discover hidden defects in advance, and facilitate maintenance personnel to timely check and replace the problematic circuit breaker parts;

[0019] 2. The hardware of the present invention adopts a small and compact caliper, which can be flexibly applied to various complex working conditions. While ensuring the sampling rate and resolution, the stability is improved. At the same time, it has a pre-analog filtering function, a longer waveform recording time, an independent setting of the trigger level and a custom filtering function; the software is more intelligent, which reduces the probability of manual judgment errors and reduces the difficulty of operation. Compared with the existing defect discrimination algorithm, the Pearson correlation coefficient is used for defect identification, which can not only complete waveform calculation, waveform comparison analysis and auxiliary function judgment, but also saves the time of defect discrimination compared with other simple programs, and is more suitable for the needs of on-site work; in terms of practicality, it has both portability and scalability, and the human-computer interaction interface is powerful and can meet some daily command requirements. The handheld design with a built-in power supply enhances the portability of use, and the acquisition card port is easy to replace to meet different sampling conditions; the sampling locking function of the caliper prevents the entry of clutter, so that after adjusting the caliper and changing the wiring, there will be no software system disconnection phenomenon, which reduces the frequent restart of the host power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the test system of the present invention. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0022] like Figure 1As shown, a high-voltage circuit breaker opening and closing coil current testing system, the innovation of which is: comprising a signal acquisition module, a data processing module, a data storage module, a defect diagnosis module and a human-computer interaction module, the signal acquisition module, the data processing module, the data storage module and the defect diagnosis module are connected in sequence, and the data storage module and the defect diagnosis module are both connected to the human-computer interaction module;

[0023] The signal acquisition module is located on the current sampling clamp, detects the opening and closing coil current of the circuit breaker through the current sensor, and inputs the electrical signal into the data processing module after analog filtering and A / D conversion;

[0024] The data processing module performs filtering processing on the original current digital signal;

[0025] The data storage module receives and stores the circuit breaker opening and closing coil current processed by the data processing module, and stores the historical data of the circuit breaker opening and closing coil current; the data in the data storage module is called by the human-computer interaction module on the one hand, and the current coil opening and closing current or historical current data of the current test is updated in real time on the display; on the other hand, it is called and input into the defect diagnosis module, and the defect diagnosis module calculates the Pearson correlation coefficient of the opening and closing coil current, and determines the current state of the high-voltage circuit breaker based on the current and historical Pearson correlation coefficients of the coil current, and predicts the development trend of the future circuit breaker operation state. The defect diagnosis results and trend development of the defect diagnosis module will be displayed in the human-computer interaction module.

[0026] The signal acquisition module is composed of a Hall current sensor, an analog filter and an A / D conversion module, and collects the current of the opening and closing coil after the circuit breaker is actuated. The pre-filter performs preliminary noise reduction on the signal, and then inputs it into the data processing module through analog-to-digital conversion. At the same time, the module can independently set the trigger pulse and has a sampling locking function. When the sampling clamp is disconnected, the current signal sampling and filtering are no longer performed.

[0027] The data processing module is a secondary precision filter of the digital filter, which performs Kalman filtering on the rough digital signal of the signal acquisition module to obtain a smooth current signal curve, which is stored in the data storage module and input into the defect diagnosis module to determine the operating status of the circuit breaker.

[0028] The data storage module is a data receiving terminal and a disk. The data storage module can be replaced by plugging and unplugging a memory card, and the data transmission module can be updated by Bluetooth and wired transmission. On the one hand, it stores the historical data of the circuit breaker opening and closing coil current, and on the other hand, it receives the digital signal data of the circuit breaker opening and closing coil current sent by the signal acquisition module and the data processing module, and forms a new historical data packet in the disk. At the same time, it has a read-write port for exchanging data / commands with the fault diagnosis module and the human-computer interaction module.

[0029] The defect diagnosis module receives the currently collected and filtered opening and closing coil current data, extracts the historical data of the circuit breaker from the data storage module, and uses the segmented Pearson correlation coefficient to compare the new current data with multiple historical data to obtain the operating status and change trend of the circuit breaker. At the same time, it has a read-write port for exchanging data / commands with the human-computer interaction module;

[0030] The specific process of the segmented Pearson correlation coefficient is as follows: first, determine the inflection point of the current waveform of the circuit breaker opening and closing coil, and segment the current waveform according to the inflection point into four or five segments; then, calculate the Pearson correlation coefficient on each monotonous curve segment; when the number of sampling points of the new current data and the historical data in the segment is different, the length principle is adopted, and the short data segment is expanded by linear interpolation. When the dimensions of the two data segments are consistent, the Pearson correlation coefficient of the two is calculated, which is the Pearson correlation coefficient of the segment; finally, judge the operating status of the circuit breaker. When each segment shows a strong correlation, it indicates that the circuit breaker is in good condition. When the correlation of a certain segment is weak, there is reason to suspect that the circuit breaker is in poor condition and needs to be further diagnosed in combination with other test items.

[0031] The human-computer interaction module has a read-write port for exchanging data / commands with the data storage module and the defect diagnosis module respectively. The currently measured or historical circuit breaker opening and closing coil current waveform can be called and displayed from the data storage module, and the good and bad status of the opening and closing coil current under this measurement can be read from the defect diagnosis module and displayed on the screen for on-site maintenance personnel to review; before performing the circuit breaker test, the maintenance personnel can update the corresponding circuit breaker historical data in the data storage module through the human-computer interaction module, and the technical personnel can also adjust and set the programs and parameters of the data processing module and the defect diagnosis module through the human-computer interaction module.

[0032] The current sampling caliper of the present invention adopts a small and compact caliper structure, a built-in Hall current sensor and an analog filter of Winson WCS1700, a bandwidth DC 30MHz, a current 30A, a sampling rate 1Ms / s, and a trigger condition is used when the opening and closing coil is energized, and a wave recorder is started to realize the function of collecting the opening and closing coil current. The caliper is provided with an opening button and an energized locking device to ensure that there is no noise input during the process of changing the caliper wiring. The sampled analog signal is connected to the single-chip microcomputer of the STM32 series STM32F407ZGT6 through the A / D conversion interface of the model AD7606, and the single-chip microcomputer performs fine Kalman filtering on the digital signal and encapsulates it into the built-in memory of the analyzer, so that the fault diagnosis module can be called at any time. The single-chip microcomputer, memory and derived sensor and other devices located inside the opening and closing coil current analyzer are powered by a rechargeable lithium battery and a power management module.

[0033] The application program written by using the disk of the dedicated PC and the Qt graphical interface realizes the integration of the functions of the data storage module, data processing module, and human-computer interaction module. The application program interface reads the circuit breaker closing and opening coil current and the historical current from the serial port, and updates the calculated correlation coefficient.

[0034] The algorithm flow of the segmented Pearson correlation coefficient: the current waveform of the circuit breaker closing and opening coil and the historical current data are segmented by the inflection point, and the 200 sampling points before or after the inflection point are required to be monotonic and less than or greater than the current value at the inflection point. The Pearson correlation coefficient of the current detection current and the historical current is calculated in each monotonic segment. Substitute the following segmented Pearson correlation coefficient formula for calculation,

[0035]

[0036] Where: r k is the Pearson correlation coefficient of the kth segment in chronological order; n k is the number of sampling points in the kth segment; i Y is the latest sampled circuit breaker closing and opening coil current, the i-th sampled data counted from the starting inflection point of each small segment; i is the historical current data of the circuit breaker opening and closing coil, the i-th sampling data counted from the starting inflection point of each small segment; It is the average value of the latest sampling and historical coil current in each segment;

[0037]

[0038] Among them: r is the Pearson coefficient of the current test and a certain historical data; m is the number of segments of the coil current according to the inflection point. When the Pearson coefficient is greater than 0.8, it indicates that the current coil current is highly similar to the historical data, and it is considered that the opening and closing coil of the circuit breaker is in good condition; when the Pearson coefficient is less than 0.5, it indicates that the current coil current is weakly similar to the historical data, and it is considered that the opening and closing coil of the circuit breaker has defects; when the Pearson coefficient is greater than 0.5 and less than 0.8, it is necessary to combine other test schemes to determine the status of the circuit breaker.

[0039] When the number of sampling points of the segmented current data is different from that of the historical data, the principle of length is adopted, and the short data is supplemented to the same length as the long data by linear interpolation. First, the difference w between the data volume of the short data segment and the long data segment is calculated, and then the short data segment is evenly divided into w+1 parts, and a data point is supplemented between each two parts by linear interpolation. Finally, the Pearson correlation coefficient with the long data segment is calculated and recorded as the Pearson correlation coefficient of the segment.

[0040] The Pearson correlation coefficient of the current test coil current data and all historical data is calculated separately to obtain a curve chart of the change of the Pearson coefficient over time. The operating status and development trend of the circuit breaker can be judged through this curve chart. At the same time, the Pearson correlation coefficient of the three-phase coil current of the circuit breaker is calculated separately, and the operating status of the coil is compared horizontally, which is convenient for operation and maintenance personnel to maintain or replace the asymmetric phase of the circuit breaker.

[0041] The present invention is powered by a self-contained power supply, which improves the convenience of on-site test work. At the same time, it provides a printing function option, which is convenient for printing and recording current waveforms and defect identification results, etc. At the same time, it has an expandable human-computer interaction interface, which is convenient for connecting with other devices to realize more additional functions. The detachable acquisition card can adapt to different sampling environments as needed.

[0042] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A high voltage circuit breaker opening and closing coil current testing system, characterized in that: It includes a signal acquisition module, a data processing module, a data storage module, a defect diagnosis module and a human-computer interaction module, wherein the signal acquisition module, the data processing module, the data storage module and the defect diagnosis module are connected in sequence, and the data storage module and the defect diagnosis module are both connected to the human-computer interaction module; The signal acquisition module is located on the current sampling clamp, detects the opening and closing coil current of the circuit breaker through the current sensor, and inputs the electrical signal into the data processing module after analog filtering and A / D conversion; The data processing module performs filtering processing on the original current digital signal; The data storage module receives and stores the circuit breaker opening and closing coil current processed by the data processing module, and stores the historical data of the circuit breaker opening and closing coil current; the data in the data storage module is called by the human-computer interaction module on the one hand, and the current coil opening and closing current or historical current data of the current test is updated in real time on the display; on the other hand, it is called and input into the defect diagnosis module, and the defect diagnosis module calculates the Pearson correlation coefficient of the opening and closing coil current, and determines the current state of the high-voltage circuit breaker based on the current and historical Pearson correlation coefficients of the coil current, and predicts the development trend of the future circuit breaker operation state. The defect diagnosis results and trend development of the defect diagnosis module will be displayed in the human-computer interaction module.

2. The high-voltage circuit breaker opening and closing coil current testing system according to claim 1 is characterized in that: The signal acquisition module is composed of a Hall current sensor, an analog filter and an A / D conversion module, and collects the current of the opening and closing coil after the circuit breaker is actuated. The pre-filter performs preliminary noise reduction on the signal, and then inputs it into the data processing module through analog-to-digital conversion. At the same time, the module can independently set the trigger pulse and has a sampling locking function. When the sampling clamp is disconnected, the current signal sampling and filtering are no longer performed.

3. The high voltage circuit breaker opening and closing coil current testing system according to claim 1 is characterized in that: The data processing module is a secondary precision filter of the digital filter, which performs Kalman filtering on the rough digital signal of the signal acquisition module to obtain a smooth current signal curve, which is stored in the data storage module and input into the defect diagnosis module to determine the operating status of the circuit breaker.

4. The high-voltage circuit breaker opening and closing coil current testing system according to claim 1 is characterized in that: The data storage module is a data receiving terminal and a disk. The data storage module can be replaced by plugging and unplugging a memory card, and the data transmission module can be updated by Bluetooth and wired transmission. On the one hand, it stores the historical data of the circuit breaker opening and closing coil current, and on the other hand, it receives the digital signal data of the circuit breaker opening and closing coil current sent by the signal acquisition module and the data processing module, and forms a new historical data packet in the disk. At the same time, it has a read-write port for exchanging data / commands with the fault diagnosis module and the human-computer interaction module.

5. The high-voltage circuit breaker opening and closing coil current testing system according to claim 1 is characterized in that: The defect diagnosis module receives the currently collected and filtered opening and closing coil current data, extracts the historical data of the circuit breaker from the data storage module, and uses the segmented Pearson correlation coefficient to compare the new current data with multiple historical data to obtain the operating status and change trend of the circuit breaker. At the same time, it has a read-write port for exchanging data / commands with the human-computer interaction module; The specific process of the segmented Pearson correlation coefficient is as follows: first, determine the inflection point of the current waveform of the circuit breaker opening and closing coil, and segment the current waveform according to the inflection point into four or five segments; then, calculate the Pearson correlation coefficient on each monotonous curve segment; when the number of sampling points of the new current data and the historical data in the segment is different, the length principle is adopted, and the short data segment is expanded by linear interpolation. When the dimensions of the two data segments are consistent, the Pearson correlation coefficient of the two is calculated, which is the Pearson correlation coefficient of the segment; finally, judge the operating status of the circuit breaker. When each segment shows a strong correlation, it indicates that the circuit breaker is in good condition. When the correlation of a certain segment is weak, there is reason to suspect that the circuit breaker is in poor condition and needs to be further diagnosed in combination with other test items.

6. The high voltage circuit breaker opening and closing coil current testing system according to claim 1 is characterized in that: The human-computer interaction module has a read-write port for exchanging data / commands with the data storage module and the defect diagnosis module respectively. The currently measured or historical circuit breaker opening and closing coil current waveform can be called and displayed from the data storage module, and the good and bad status of the opening and closing coil current under this measurement can be read from the defect diagnosis module and displayed on the screen for on-site maintenance personnel to review; before performing the circuit breaker test, the maintenance personnel can update the corresponding circuit breaker historical data in the data storage module through the human-computer interaction module, and the technical personnel can also adjust and set the programs and parameters of the data processing module and the defect diagnosis module through the human-computer interaction module.

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