Transient electric parameter opening and closing capability detection system and method for capacitor bank circuit breaker

Abstract

The invention provides a capacitor bank circuit breaker transient electric parameter on-line monitoring method, which comprises the following steps of: connecting a signal acquisition module with a power supply side or a load side connected with a circuit breaker to be detected; a signal acquisition module is used for acquiring corresponding transient voltage signals and current signals generated at one end of a power supply side or a load side when a to-be-tested circuit breaker is closed, and corresponding transient voltage data and transient current data are generated according to the acquired transient voltage signals and current signals; transmitting the transient voltage data and the transient current data to an analysis and judgment module; and when the analysis and judgment module judges that the transient current data is not smaller than the current preset value, a monitoring algorithm and a monitoring criterion are adopted to extract frequency spectrum characteristic parameters of the transient voltage data, the obtained frequency spectrum characteristic parameters are compared with a preset characteristic threshold value, and whether the opening and closing capacity of the circuit breaker is abnormal or not is determined according to a comparison result. The invention further provides an online monitoring system for the transient electric parameters of the capacitor bank circuit breaker.

Description

Technical Field

[0001] The present invention relates to the technical field of online detection of circuit breakers in power systems, and in particular to an online monitoring system and method for transient electrical parameters of a capacitor bank circuit breaker. Background Art

[0002] The importance of energy and power security and supply is becoming increasingly prominent, and the construction of a new power system has put forward new requirements for the stability and safety of power supply in the power system. As the scale of my country's power grid construction has steadily increased, line losses have increased day by day. In order to compensate for the decline in reactive power of the power grid, the State Grid Corporation will configure parallel compensation capacitors in the substation for compensation. Since the capacitor bank circuit breaker is frequently switched with the fluctuation of reactive load, the arc contact of the circuit breaker will be burned by arc during the switching process, resulting in a decrease in its opening and closing capacity. There have been many major safety accidents caused by the decline in the arc extinguishing ability of the circuit breaker in the State Grid Corporation system. How to effectively monitor the working conditions of the circuit breaker and prevent the occurrence of vicious accidents such as circuit breaker opening and closing failure is of great significance to ensuring the safe and reliable operation of the power grid.

[0003] Conventional circuit breaker detection methods include online detection and offline detection. The offline detection method is usually carried out by experienced professionals to inspect fault precursors and valuable clues, such as abnormal sounds, vibrations, oil leakage, air leakage, overheating, etc. This method has a long detection cycle, lacks specificity, and is time-consuming and labor-intensive. The online detection method is usually achieved by monitoring the circuit breaker vibration signal and the current of the opening and closing coils. The operation is complicated and is easily affected by interference factors in actual operation during detection. Summary of the invention

[0004] In view of this, it is necessary to propose a capacitor bank circuit breaker transient electrical parameter switching capacity detection system with short detection cycle and simple operation.

[0005] It is also necessary to provide a method for detecting the transient electrical parameter switching capacity of a capacitor bank circuit breaker with a short detection cycle and simple operation.

[0006] A capacitor bank circuit breaker transient electrical parameter switching capacity detection system, comprising: a signal acquisition module, a signal transmission module, an analysis and judgment module,

[0007] The signal acquisition module is connected to the power supply side or the load side of the circuit breaker to be tested, and is used to collect the corresponding transient voltage signal and current signal generated by one end of the power supply side or the load side when the circuit breaker to be tested is closed, and generate corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal;

[0008] The signal transmission module is electrically connected to the signal acquisition module, and the signal transmission module is used to transmit the transient voltage data and the transient current data to the analysis and judgment module;

[0009] The analysis and judgment module establishes communication with the signal transmission module. The analysis and judgment module is used to extract the frequency spectrum characteristic parameters of the transient voltage data by using the monitoring algorithm and the monitoring criterion when it is judged that the transient current data is not less than the preset current value, and compare the obtained frequency spectrum characteristic parameters with the preset characteristic threshold value, and determine whether the opening and closing capacity of the circuit breaker is abnormal based on the comparison result.

[0010] A method for detecting the transient electrical parameter switching capability of a capacitor bank circuit breaker comprises the following steps:

[0011] Connect the signal acquisition module to the power supply side or the load side connected to the circuit breaker to be tested, use the signal acquisition module to collect the corresponding transient voltage signal and current signal generated at one end of the power supply side or the load side when the circuit breaker to be tested is closed, and generate corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal;

[0012] Transmitting transient voltage data and transient current data to the analysis and judgment module;

[0013] When the analysis and judgment module determines that the transient current data is not less than the preset current value, it uses the monitoring algorithm and monitoring criteria to extract the frequency spectrum characteristic parameters of the transient voltage data, and compares the obtained frequency spectrum characteristic parameters with the preset characteristic threshold value, and determines whether the opening and closing capacity of the circuit breaker is abnormal based on the comparison result.

[0014] In the above-mentioned capacitor bank circuit breaker transient electrical parameter online monitoring system and method, the signal acquisition module is connected to the power side or the load side connected to the circuit breaker to be tested, and the signal acquisition module is used to collect the corresponding transient voltage signal and current signal generated by one end of the power side or the load side when the circuit breaker to be tested is closed, and the corresponding transient voltage data and transient current data are generated according to the collected transient voltage signal and current signal; when the analysis and judgment module judges that the transient current data is not less than the preset current value, the monitoring algorithm and the monitoring criterion are used to extract the frequency spectrum characteristic parameters of the transient voltage data, and the obtained frequency spectrum characteristic parameters are compared with the preset characteristic threshold value, and whether the opening and closing capacity of the circuit breaker is abnormal is determined according to the comparison result, and the opening and closing capacity of the circuit breaker can be detected without the need for experienced professionals to patrol and check for fault precursors and valuable clues or by monitoring the vibration signal of the circuit breaker and the current of the opening and closing coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the application of the capacitor bank circuit breaker transient electrical parameter switching capacity detection system of the present application;

[0016] Figure 2 This is a functional module diagram of the capacitor bank circuit breaker transient electrical parameter switching capability detection system of the present application;

[0017] Figure 3 Schematic diagram of the functional units of the sensing unit.

[0018] Figure 4 This is a schematic diagram of spectrum monitoring corresponding to the closing of the circuit breaker under test.

[0019] Figure 5 This is a flow chart of the method for detecting the transient electrical parameter switching capability of a capacitor bank circuit breaker of the present application.

[0020] In the figure, there are a signal acquisition module 20, a sensing unit 21, a voltage sensor 210, a current sensor 211, a filtering unit 22, an amplifying unit 23, a GPS time synchronization unit 24, a signal reading unit 25, a signal conversion unit 26, a signal transmission module 30, an analysis and judgment module 40, an analysis and start unit 41, a spectrum characteristic parameter extraction unit 42, an opening and closing ability judgment unit 43, and a shell 50. DETAILED DESCRIPTION

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Please see Figure 1 and Figure 2 The capacitor bank circuit breaker transient electrical parameter opening and closing capacity detection system 10 provided in the present application includes: a signal acquisition module 20, a signal transmission module 30, and an analysis and judgment module 40. The signal acquisition module 20 is connected to the power supply side or the load side connected to the circuit breaker to be tested, and the signal acquisition module 20 is used to collect the corresponding transient voltage signal and current signal generated by one end of the power supply side or the load side when the circuit breaker to be tested is closed, and generate corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal; the signal transmission module 30 is electrically connected to the signal acquisition module 20, and the signal transmission module 30 is used to transmit the transient voltage data and the transient current data to the analysis and judgment module 40; the analysis and judgment module 40 establishes communication with the signal transmission module 30, and the analysis and judgment module 40 is used to extract the frequency spectrum characteristic parameters of the transient voltage data by using the monitoring algorithm and the monitoring criterion when it is judged that the transient current data is not less than the preset current value, and compare the obtained frequency spectrum characteristic parameters with the preset characteristic threshold value, and determine whether the opening and closing capacity of the circuit breaker is abnormal according to the comparison result.

[0023] Furthermore, the signal acquisition module 20 includes: a sensing unit 21, a filtering unit 22, an amplifying unit 23, a GPS time synchronization unit 24, a signal reading unit 25 and a signal conversion unit 26. The sensing unit 21 is installed on the power supply side or the load side connected to the circuit breaker to be tested, the sensing unit 21 is electrically connected to the filtering unit 22, the filtering unit 22 is electrically connected to the amplifying unit 23, and the signal reading unit 25 is electrically connected to the amplifying unit 23, the GPS time synchronization unit 24 and the signal conversion unit 26.

[0024] The sensing unit 21 is used to sense the corresponding transient voltage and current generated at one end of the power supply side or the load side when the circuit breaker to be tested is closed, and to generate corresponding transient voltage signals and transient current signals;

[0025] The filtering unit 22 filters the transient voltage signal and the transient current signal and provides them to the amplifying unit 23;

[0026] The amplifying unit 23 amplifies the filtered transient voltage signal and the transient current signal, and provides the amplified transient voltage signal and the transient current signal to the signal reading unit 25;

[0027] The GPS time synchronization unit 24 controls the acquisition frequency of the signal reading unit 25 so that the signal reading unit 25 reads the corresponding target transient voltage signal and target transient current signal from the received transient voltage signal and transient current signal, and the signal reading unit 25 provides the target transient voltage signal and target transient current signal to the signal conversion unit 26;

[0028] The signal conversion unit 26 performs analog-to-digital conversion on the target transient voltage signal and the target transient current signal to obtain target transient voltage data and target transient current data, and provides the target transient voltage data and the target transient current data to the signal transmission module 30 .

[0029] The above-mentioned spectrum characteristic parameters include: the collected closing voltage characteristic frequency band f0 of the circuit breaker, the maximum peak point f max , and the frequency band energy ratio k of different frequency bands; correspondingly, the preset characteristic threshold includes the frequency band energy preset ratio k1 of the first frequency band and the third frequency band, and the second frequency band; the analysis and judgment module 40 includes an analysis start unit 41, a spectrum characteristic parameter extraction unit 42 and a switching capacity judgment unit 43, the analysis start unit 41 is electrically connected to the spectrum characteristic parameter extraction unit 42, the spectrum characteristic parameter extraction unit 42 is electrically connected to the switching capacity judgment unit 43, and the analysis start unit 41 is used to output a start signal to the spectrum characteristic parameter extraction unit 42 when it is judged that the target transient current data is not less than the current preset value;

[0030] The spectrum characteristic parameter extraction unit 42 is used to respond to the start signal, analyze the spectrum distribution and power spectrum distribution of the target transient voltage data through the Fourier transform algorithm and the preset first frequency band, second frequency band, and third frequency band, and extract the maximum peak point f from the spectrum. max , and determine the frequency point corresponding to A times the amplitude, so as to set the upper and lower limits of the characteristic frequency band f0, where f0 = f A+ -f A- , f A+ Indicates the upper limit of the characteristic frequency band f0, the frequency point corresponding to A times the amplitude, f A- represents the lower limit of the characteristic frequency band f0; and according to the power spectrum distribution, calculating the frequency band energy ratio k of the first frequency band and the third frequency band, wherein, E1 is the energy of the first frequency band, E2 is the energy of the third frequency band, and F n is the frequency amplitude of the sampling point, Δf is the frequency difference between adjacent sampling points, R is the frequency difference between the upper and lower limits of the spectrum distribution, and f1 and f2 are the starting and ending frequencies of the first frequency band, respectively; wherein, the first frequency band, the second frequency band, and the third frequency band are determined in the following manner: the frequency range in which the circuit breaker closing voltage signal may appear is divided into the first frequency band, the second frequency band, and the third frequency band. The voltage signal frequency in the first frequency band is low. When the circuit breaker is closed normally, the closing voltage signal frequency distribution is limited, and the voltage power spectrum is mainly distributed in this part; the second frequency band is the transition of the voltage frequency signal between the first and third frequency bands, which is within an acceptable range. When the circuit breaker opening and closing capacity is normal, part of the voltage signal frequency will also fall in this frequency band, which serves as a buffer segment for spectrum signal judgment and is used to smoothly transition parts of different frequency intervals to ensure the accuracy and continuity of signal analysis; the voltage signal frequency in the third frequency band is high. When the circuit breaker opening and closing performance decreases, the high-frequency component of the closing voltage signal increases, and the voltage power spectrum of this part increases significantly.

[0031] The opening and closing capacity judgment unit 43 is used to judge that the opening and closing capacity of the circuit breaker is abnormal when the characteristic frequency band f0 falls outside the second frequency band, or the frequency band energy ratio k of the first frequency band to the third frequency band is not greater than the preset ratio k1; the opening and closing capacity judgment unit 43 is also used to judge that the opening and closing capacity of the circuit breaker is normal when the characteristic frequency band f0 falls within the second frequency band and the frequency band energy ratio k of the first frequency band to the third frequency band is greater than the preset ratio k1. In this embodiment, the opening and closing capacity judgment unit 43 is also used to judge that the characteristic frequency band f0 falls within the second frequency band and the frequency band energy ratio k of the first frequency band to the third frequency band is not greater than the preset ratio k1, and the opening and closing capacity of the circuit breaker is abnormal; the opening and closing capacity judgment unit 43 is also used to judge that the characteristic frequency band f0 falls outside the second frequency band and the frequency band energy ratio k of the first frequency band to the third frequency band is greater than the preset ratio k1, and the opening and closing capacity of the circuit breaker is abnormal.

[0032] For example, the first frequency band ranges from 50-50kHz, the second frequency band is 50-300kHz, and the third frequency band is 50-1MHz, and the preset ratio k1 is 80%; the current preset value is 0.01kA, and when the analysis start unit 41 determines that the target transient current data is not less than the current preset value for the first time, it will determine that the target transient current data is not less than the current preset value for the first time as the breakdown instant t1, and output the start signal and the breakdown instant t1 to the spectrum feature parameter extraction unit 42; the spectrum feature parameter extraction unit 42 responds to the start signal, and analyzes the spectrum distribution and power spectrum distribution of the transient voltage data within 3ms after the breakdown instant t1 of the target transient voltage data through the Fourier transform algorithm and the preset first frequency band, second frequency band, and third frequency band.

[0033] Furthermore, the capacitor bank circuit breaker transient electrical parameter opening and closing capacity detection system 10 also includes a housing 50, the signal acquisition module 20 and the signal transmission module 30 are encapsulated in the housing 50, and the housing 50 is fixed on the drain wires at both ends of the power supply side or the load side of the capacitor bank circuit breaker by snap-fitting; the sensor unit 21 of the signal acquisition module 20 includes a voltage sensor and a current sensor with a bandwidth of 50Hz to 1MHz; the filter unit 22 uses a bandpass filter with a bandwidth of 50-1MHz. In other embodiments, a capacitor bank circuit breaker transient electrical parameter opening and closing capacity detection system can be set on both the power supply side and the load side when the circuit breaker to be tested is closed, so that the opening and closing performance of both ends of the circuit breaker to be tested can be tested at the same time to ensure that the power grid can operate more safely and reliably.

[0034] In order to make the technical solution of this application clearly understood, the following examples are given: Please also refer to Figure 3 The voltage sensor 210 and the current sensor 211 obtain an electrical signal proportional to the actual quantity to be measured. After the obtained electrical signal passes through the filtering unit 22 and the amplifying unit 23, the GPS time synchronization unit 24 controls the acquisition frequency of the signal reading unit 25. The sampled voltage signal and current signal are transmitted to the signal conversion unit 26. The signal conversion unit 26 converts the sampled voltage signal and current signal into digital signals, and then uses the signal transmission module 30 to send them to the upper industrial computer. The upper industrial computer is provided with the analysis and judgment module 40. For example, the analysis and judgment module 40 is formed by the detection software program running in the upper industrial computer. The analysis and judgment module 40 uses the current signal as a trigger mechanism, and starts to analyze the frequency spectrum distribution and power spectrum distribution of the transient voltage signal through the Fourier transform (FFT) algorithm, and extracts the maximum peak point f max And the maximum peak point f max The frequency point corresponding to 0.0025 (A = 0.0025) times the amplitude determines the upper and lower limits of the characteristic frequency band f0, where f0 = f0.005fmax+ -f 50Hz , after obtaining the signal power spectrum of the third frequency band 50-50kHz, calculate the frequency band energy E[50-50k] of the first frequency band 50-300kHz and its proportion k to the frequency band energy E[50-1M] (i.e., total energy) of the third frequency band 50-1MHz, wherein the formula for calculating the frequency band energy E[50-50k] and proportion k of the first frequency band 50-300kHz is as follows:

[0035]

[0036] For example Figure 4 As shown, if the maximum peak point and characteristic frequency band extracted from the two collected transient voltage data are outside 50-300kHz, and the proportion of 50-50kHz frequency band energy to total energy is less than 80%, it is determined that a circuit breaker arc fault occurs, otherwise no arc fault occurs.

[0037] For further information, please also see Figure 5 The present application also provides a method for detecting the transient electrical parameter switching capability of a capacitor bank circuit breaker, comprising the following steps:

[0038] Connect the signal acquisition module to the power supply side or the load side connected to the circuit breaker to be tested, use the signal acquisition module to collect the corresponding transient voltage signal and current signal generated at one end of the power supply side or the load side when the circuit breaker to be tested is closed, and generate corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal;

[0039] When it is determined that the transient current data is not less than the preset current value, for example, the preset current value is 0.01kA, it means that the circuit breaker has been closed. The monitoring algorithm and monitoring criterion are used to extract the frequency spectrum characteristic parameters of the transient voltage data, and the obtained frequency spectrum characteristic parameters are compared with the preset characteristic threshold value, and it is determined whether the opening and closing capacity of the circuit breaker is abnormal based on the comparison result.

[0040] The step of "generating corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal" specifically includes: filtering the transient voltage signal and the transient current signal and providing them to the amplification unit; amplifying the filtered transient voltage signal and the transient current signal;

[0041] The GPS time synchronization unit is used to control the acquisition frequency so as to read the corresponding target transient voltage signal and target transient current signal from the amplified transient voltage signal and transient current signal; after analog-to-digital conversion of the target transient voltage signal and target transient current signal, the target transient voltage data and target transient current data are obtained.

[0042] The spectrum characteristic parameters include: the characteristic frequency band f0 of the closing voltage of the collected circuit breaker, the maximum peak point f max , and the frequency band energy ratio k of different frequency bands; correspondingly, the preset characteristic threshold includes the preset frequency band energy ratio k1 and the second frequency band between the first frequency band and the third frequency band; the first frequency band, the second frequency band and the third frequency band are determined in the following manner: the frequency range in which the circuit breaker closing voltage signal may appear is divided into the first frequency band, the second frequency band and the third frequency band. The voltage signal frequency in the first frequency band is low. When the circuit breaker is closed normally, the frequency distribution of the closing voltage signal is limited, and the voltage power spectrum is mainly distributed in this part; the second frequency band is the transition of the voltage frequency signal between the first and third frequency bands, which is within an acceptable range. When the circuit breaker opening and closing capacity is normal, part of the voltage signal frequency will also fall in this frequency band, which is used as a buffer segment for spectrum signal judgment and is used to smoothly transition parts of different frequency intervals to ensure the accuracy and continuity of signal analysis; the voltage signal frequency in the third frequency band is high. When the circuit breaker opening and closing performance decreases, the high-frequency component of the closing voltage signal increases, and the voltage power spectrum of this part increases significantly.

[0043] Furthermore, the steps of "using a monitoring algorithm and a monitoring criterion to extract the frequency spectrum characteristic parameters of the transient voltage data, and comparing the obtained frequency spectrum characteristic parameters with a preset characteristic threshold, and determining whether the opening and closing capacity of the circuit breaker is abnormal according to the comparison result" are specifically as follows:

[0044] The frequency spectrum distribution and power spectrum distribution of the target transient voltage data are analyzed by Fourier transform algorithm and the preset first frequency band, second frequency band and third frequency band, and the maximum peak point f is extracted from the frequency spectrum. max , and determine the frequency point corresponding to A times the amplitude, so as to set the upper and lower limits of the characteristic frequency band f0, where f0 = f A+ -f A- , f A+ Indicates the upper limit of the characteristic frequency band f0, the frequency point corresponding to A times the amplitude, f A- represents the lower limit of the characteristic frequency band f0; and according to the power spectrum distribution, calculating the frequency band energy ratio k of the first frequency band and the third frequency band, wherein, E1 is the energy of the first frequency band, E2 is the energy of the third frequency band, and F n is the frequency amplitude of the sampling point, Δf is the frequency difference between adjacent sampling points, R is the frequency difference between the upper and lower limits of the spectrum distribution, f1 and f2 are the start and end frequencies of the first frequency band respectively;

[0045] When it is determined that the characteristic frequency band f0 falls outside the second frequency band, y=1, or the frequency band energy ratio k between the first frequency band and the third frequency band is not greater than the preset ratio k1, x=1, and it is determined that the circuit breaker's opening and closing capacity is abnormal; when it is determined that the characteristic frequency band f0 falls within the second frequency band, y=0, and the frequency band energy ratio k between the first frequency band and the third frequency band is greater than the preset ratio k1, x=0, and the circuit breaker's opening and closing capacity is normal, and then the circuit breaker jumps to detect the next closing signal.

[0046] Among them, when it is judged that the target transient current data is not less than the preset current value for the first time, the moment when the target transient current data is judged to be not less than the preset current value for the first time is taken as the breakdown instant t1, and the frequency spectrum distribution and power spectrum distribution of the transient voltage data within 3ms after the breakdown instant t1 of the target transient voltage data are analyzed through the Fourier transform algorithm and the preset first frequency band, second frequency band, and third frequency band.

[0047] Furthermore, when it is determined that the characteristic frequency band f0 falls within the second frequency band, y=0, and the frequency band energy ratio k between the first frequency band and the third frequency band is not greater than the preset ratio k1, x=1, and it is determined that the circuit breaker's opening and closing capacity is abnormal; when it is determined that the characteristic frequency band f0 falls outside the second frequency band, y=1, and the frequency band energy ratio k between the first frequency band and the third frequency band is greater than the preset ratio k1, x=0, and it is determined that the circuit breaker's opening and closing capacity is abnormal.

[0048] The modules or units in this application can be combined, divided and deleted according to actual needs. The above disclosure is only the preferred embodiment of the present invention, and of course it cannot be used to limit the scope of the rights of the present invention. Those skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A capacitor bank circuit breaker transient electrical parameter switching capacity detection system, comprising: Signal acquisition module, signal transmission module, analysis and judgment module, The signal acquisition module is connected to the power supply side or the load side of the circuit breaker to be tested, and is used to collect the corresponding transient voltage signal and current signal generated by one end of the power supply side or the load side when the circuit breaker to be tested is closed, and generate corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal; The signal transmission module is electrically connected to the signal acquisition module, and the signal transmission module is used to transmit the transient voltage data and the transient current data to the analysis and judgment module; The analysis and judgment module establishes communication with the signal transmission module. The analysis and judgment module is used to extract the frequency spectrum characteristic parameters of the transient voltage data by using the monitoring algorithm and the monitoring criterion when it is judged that the transient current data is not less than the preset current value, and compare the obtained frequency spectrum characteristic parameters with the preset characteristic threshold value, and determine whether the opening and closing capacity of the circuit breaker is abnormal based on the comparison result.

2. The capacitor bank circuit breaker transient electrical parameter switching capability detection system according to claim 1, characterized in that: The signal acquisition module includes: a sensing unit, a filtering unit, an amplifying unit, a GPS time synchronization unit, a signal reading unit and a signal conversion unit, wherein the sensing unit is installed on the power supply side or the load side connected to the circuit breaker to be tested, the sensing unit is electrically connected to the filtering unit, the filtering unit is electrically connected to the amplifying unit, and the signal reading unit is electrically connected to the amplifying unit, the GPS time synchronization unit and the signal conversion unit; The sensing unit is used to sense the corresponding transient voltage and current generated at one end of the power supply side or the load side when the circuit breaker to be tested is closed, and to generate corresponding transient voltage signals and transient current signals; A filtering unit, which filters the transient voltage signal and the transient current signal and then provides them to the amplifying unit; an amplifying unit, amplifying the filtered transient voltage signal and the transient current signal, and providing the amplified transient voltage signal and the transient current signal to the signal reading unit; The GPS time synchronization unit controls the acquisition frequency of the signal reading unit so that the signal reading unit reads the corresponding target transient voltage signal and target transient current signal from the received transient voltage signal and transient current signal, and the signal reading unit provides the target transient voltage signal and target transient current signal to the signal conversion unit; The signal conversion unit performs analog-to-digital conversion on the target transient voltage signal and the target transient current signal to obtain target transient voltage data and target transient current data, and provides the target transient voltage data and the target transient current data to the signal transmission module.

3. The capacitor bank circuit breaker transient electrical parameter switching capability detection system according to claim 2, characterized in that: The spectrum characteristic parameters include: the characteristic frequency band f0 of the closing voltage of the collected circuit breaker, the maximum peak point f max , and the frequency band energy ratio k of different frequency bands; correspondingly, the preset characteristic threshold includes the frequency band energy preset ratio k1 of the first frequency band and the third frequency band, and the second frequency band; the analysis and judgment module includes an analysis start unit, a spectrum characteristic parameter extraction unit and a switching capacity judgment unit, the analysis start unit is electrically connected to the spectrum characteristic parameter extraction unit, the spectrum characteristic parameter extraction unit is electrically connected to the switching capacity judgment unit, and the analysis start unit is used to output a start signal to the spectrum characteristic parameter extraction unit when it is judged that the target transient current data is not less than the current preset value; The spectrum characteristic parameter extraction unit is used to respond to the start signal, analyze the spectrum distribution and power spectrum distribution of the target transient voltage data through the Fourier transform algorithm and the preset first frequency band, second frequency band, and third frequency band, and extract the maximum peak point f from the spectrum. max , and determine the frequency point corresponding to A times the amplitude, so as to set the upper and lower limits of the characteristic frequency band f0, where f0 = f A+ -f A- , f A+ Indicates the upper limit of the characteristic frequency band f0, the frequency point corresponding to A times the amplitude, f A- represents the lower limit of the characteristic frequency band f0; and according to the power spectrum distribution, calculating the frequency band energy ratio k of the first frequency band and the third frequency band, wherein, E1 is the energy of the first frequency band, E2 is the energy of the third frequency band, and F n is the frequency amplitude of the sampling point, Δf is the frequency difference between adjacent sampling points, R is the frequency difference between the upper and lower limits of the spectrum distribution, f1 and f2 are the start and end frequencies of the first frequency band respectively; The opening and closing capacity judgment unit is used to judge that the opening and closing capacity of the circuit breaker is abnormal when the characteristic frequency band f0 falls outside the second frequency band, or the frequency band energy ratio k between the first frequency band and the third frequency band is not greater than the preset ratio k1; the opening and closing capacity judgment unit is used to judge that the opening and closing capacity of the circuit breaker is normal when the characteristic frequency band f0 falls within the second frequency band and the frequency band energy ratio k between the first frequency band and the third frequency band is greater than the preset ratio k1.

4. The capacitor bank circuit breaker transient electrical parameter switching capability detection system according to claim 3, characterized in that: The opening and closing capacity judgment unit is used to judge that the opening and closing capacity of the circuit breaker is abnormal when the characteristic frequency band f0 falls within the second frequency band and the frequency band energy ratio k between the first frequency band and the third frequency band is not greater than the preset ratio k1; the opening and closing capacity judgment unit is used to judge that the opening and closing capacity of the circuit breaker is abnormal when the characteristic frequency band f0 falls outside the second frequency band and the frequency band energy ratio k between the first frequency band and the third frequency band is greater than the preset ratio k1.

5. The capacitor bank circuit breaker transient electrical parameter switching capability detection system according to claim 3 or 4, characterized in that: The first frequency band, the second frequency band and the third frequency band are determined in the following way: the frequency range in which the circuit breaker closing voltage signal may appear is divided into the first frequency band, the second frequency band and the third frequency band. The voltage signal frequency in the first frequency band is low. When the circuit breaker is closed normally, the frequency distribution of the closing voltage signal is limited, and the voltage power spectrum is mainly distributed in this part; the second frequency band is the transition of the voltage frequency signal between the first and third frequency bands, which is within an acceptable range. When the circuit breaker opening and closing capacity is normal, part of the voltage signal frequency will also fall in this frequency band, which serves as a buffer segment for spectrum signal judgment and is used to smoothly transition parts of different frequency intervals to ensure the accuracy and continuity of signal analysis; the voltage signal frequency in the third frequency band is high. When the circuit breaker opening and closing performance decreases, the high-frequency component of the closing voltage signal increases, and this part of the voltage power spectrum increases significantly.

6. The capacitor bank circuit breaker transient electrical parameter switching capability detection system according to claim 5, characterized in that: The first frequency band ranges from 50 to 50 kHz, the second frequency band is from 50 to 300 kHz, and the third frequency band is from 50 to 1 MHz. The preset ratio k1 is 80%; the preset current value is 0.01 kA. The analysis start unit is used to determine that the target transient current data is not less than the preset current value for the first time, and when it is determined that the target transient current data is not less than the preset current value for the first time, the moment when the target transient current data is determined to be not less than the preset current value for the first time is used as the breakdown instant t1, and output the start signal and the breakdown instant t1 to the spectrum feature parameter extraction unit; The spectrum characteristic parameter extraction unit is used to respond to the start signal, and analyze the spectrum distribution and power spectrum distribution of the transient voltage data within 3ms after the breakdown moment t1 of the target transient voltage data through the Fourier transform algorithm and the preset first frequency band, second frequency band and third frequency band.

7. The capacitor bank circuit breaker transient electrical parameter switching capability detection system according to claim 2, characterized in that: The capacitor bank circuit breaker transient electrical parameter opening and closing capacity detection system includes a shell, the signal acquisition module and the signal transmission module are encapsulated in the shell, and the shell is fixed to the drainage lines at both ends of the power supply side or the load side of the capacitor bank circuit breaker by snap-fitting; the signal acquisition module is a voltage and current sensor with a bandwidth of 50Hz to 1MHz; the filtering unit adopts a bandpass filter with a bandwidth of 50-1MHz.

8. A method for detecting the transient electrical parameter switching capability of a capacitor bank circuit breaker, characterized in that: The following steps are involved: Connect the signal acquisition module to the power supply side or the load side connected to the circuit breaker to be tested, use the signal acquisition module to collect the corresponding transient voltage signal and current signal generated at one end of the power supply side or the load side when the circuit breaker to be tested is closed, and generate corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal; When it is determined that the transient current data is not less than the preset current value, the monitoring algorithm and monitoring criteria are used to extract the frequency spectrum characteristic parameters of the transient voltage data, and the obtained frequency spectrum characteristic parameters are compared with the preset characteristic threshold value, and it is determined whether the opening and closing capacity of the circuit breaker is abnormal based on the comparison result.

9. The method for detecting the transient electrical parameter switching capability of a capacitor bank circuit breaker according to claim 8, characterized in that: The step of "generating corresponding transient voltage data and transient current data according to the collected transient voltage signal and current signal" is specifically: filtering the transient voltage signal and the transient current signal and providing them to the amplification unit; amplifying the filtered transient voltage signal and the transient current signal; The GPS time synchronization unit is used to control the acquisition frequency so as to read the corresponding target transient voltage signal and target transient current signal from the amplified transient voltage signal and transient current signal; After the target transient voltage signal and the target transient current signal are analog-to-digital converted, the target transient voltage data and the target transient current data are obtained.

10. The method for detecting the transient electrical parameter switching capability of a capacitor bank circuit breaker according to claim 8, characterized in that: The spectrum characteristic parameters include: the characteristic frequency band f0 of the closing voltage of the collected circuit breaker, the maximum peak point f max , and the frequency band energy ratio k of different frequency bands; correspondingly, the preset characteristic threshold includes the preset frequency band energy ratio k1 of the first frequency band and the third frequency band, the second frequency band; wherein the first frequency band, the second frequency band, and the third frequency band are determined by the following method: the frequency range in which the circuit breaker closing voltage signal may appear is divided into the first frequency band, the second frequency band, and the third frequency band. The voltage signal frequency in the first frequency band is low. When the circuit breaker is closed normally, the closing voltage signal frequency distribution is limited, and the voltage power spectrum is mainly distributed in this part; the second frequency band is the transition of the voltage frequency signal between the first and third frequency bands, which is within the acceptable range. The circuit breaker When the opening and closing capacity of the circuit breaker is normal, part of the voltage signal frequency will also fall into this frequency band, which serves as a buffer segment for spectrum signal judgment and is used to smoothly transition between parts of different frequency intervals to ensure the accuracy and continuity of signal analysis; the voltage signal frequency in the third frequency band is high, and when the opening and closing performance of the circuit breaker decreases, the high-frequency component of the closing voltage signal increases, and the power spectrum of this part of the voltage increases significantly; the specific steps of "using monitoring algorithms and monitoring criteria to extract the spectrum characteristic parameters of transient voltage data, and compare the obtained spectrum characteristic parameters with the preset characteristic thresholds, and determine whether the opening and closing capacity of the circuit breaker is abnormal based on the comparison results" are: The frequency spectrum distribution and power spectrum distribution of the target transient voltage data are analyzed by Fourier transform algorithm and the preset first frequency band, second frequency band and third frequency band, and the maximum peak point f is extracted from the frequency spectrum. max , and determine the frequency point corresponding to A times the amplitude, so as to set the upper and lower limits of the characteristic frequency band f0, where f0 = f A+ -f A- , f A+ Indicates the upper limit of the characteristic frequency band f0, the frequency point corresponding to A times the amplitude, f A- represents the lower limit of the characteristic frequency band f0; and according to the power spectrum distribution, calculating the frequency band energy ratio k of the first frequency band and the third frequency band, wherein, E1 is the energy of the first frequency band, E2 is the energy of the third frequency band, and F n is the frequency amplitude of the sampling point, Δf is the frequency difference between adjacent sampling points, R is the frequency difference between the upper and lower limits of the spectrum distribution, f1 and f2 are the start and end frequencies of the first frequency band respectively; When it is determined that the characteristic frequency band f0 falls outside the second frequency band, or the frequency band energy ratio k between the first frequency band and the third frequency band is not greater than the preset ratio k1, it is determined that the circuit breaker opening and closing capacity is abnormal; when it is determined that the characteristic frequency band f0 falls within the second frequency band, and the frequency band energy ratio k between the first frequency band and the third frequency band is greater than the preset ratio k1, it is determined that the circuit breaker opening and closing capacity is normal.

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