A method for measuring synchronization of opening and closing of a multi-vacuum interrupter switch device

Abstract

This invention discloses a method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear. The method is based on a measurement system comprising a power supply module, a control module, a data acquisition and measurement module, and a post-processing module. The data acquisition and measurement module includes a high-voltage probe connected across the two ends of the equipment and a vibration sensor installed on the side of the stationary contact cover of each vacuum interrupter. During measurement, the control module controls the power supply and executes the opening and closing operations; the data acquisition and measurement module simultaneously acquires arc voltage and vibration signals; the post-processing module processes the raw data, extracts the moment of initial opening and / or initial closing of each break, and obtains the synchronicity measurement results. Through non-invasive sensor configuration and dual-signal synchronous processing, the method solves the problem of not being able to directly measure each break due to the equipment's sealed design, overcomes the shortcomings of low accuracy in single-signal detection and difficulty in distinguishing the action moments of each break, and significantly improves the accuracy of synchronicity measurement.

Description

Technical Field

[0001] This invention relates to the field of condition monitoring and fault diagnosis technology for high-voltage electrical equipment, and in particular to a method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear. Background Technology

[0002] Currently, the power transmission and distribution sector is developing towards high voltage and ultra-high voltage, placing higher voltage-level breaking requirements on switchgear. Multi-vacuum-break switchgear has advantages such as high dielectric recovery strength and fast recovery rate. Utilizing the superior arc-extinguishing performance of series vacuum short gaps, it solves the insulation saturation problem of single-break vacuum long gaps, and has broad application prospects.

[0003] In high-voltage multi-vacuum break switchgear, the synchronicity of the opening and closing of each vacuum break during operation is crucial for ensuring safe and reliable operation. Significant differences in the opening and closing times of each break will lead to severely uneven voltage or current distribution among the breaks, potentially causing a break to experience electrical stress or arcing energy far exceeding design values. This can easily result in faults such as interruption failure, reignition, and overheating, and even lead to wider system failures. However, in multi-vacuum break switchgear, the vacuum interrupter is sealed inside a metal casing filled with insulating gas. Direct external wiring is usually not possible at the connection points of the multiple breaks, making it impossible to directly measure the voltage or current signal of each break. Directly installing displacement sensors would also affect the internal insulation, limiting its practicality.

[0004] To address the aforementioned measurement challenges, the industry currently primarily employs the following technical solutions for synchronous detection: First, a detection method based on a single vibration signal. This involves installing vibration sensors on the circuit breaker base or casing to collect vibration signals and identify energy abrupt changes as the contact action moment. In this method, the sensor installation location significantly impacts signal characteristics; the vibration signal propagation path is long, attenuates significantly, and is easily mixed with environmental interference. Signal processing requires complex algorithms such as empirical mode decomposition, resulting in high computational load, poor real-time performance, and a time offset between the energy abrupt change point and the moment the contacts just open or close, limiting measurement accuracy. Second, a detection method based on coil current and main circuit current. This involves connecting current sensors to the opening / closing coil circuit and the secondary side of the main circuit CT to record current waveforms, obtaining the command start time and contact closing / opening moment, and then calculating the opening / closing time. This method requires connection to the control circuit and CT circuit, is an invasive detection method, poses safety hazards, and is complex to implement. It can only detect the contact closing / opening moment, not the instant of opening or closing, and the measurement results include arcing time, failing to reflect the actual mechanical action moment. Furthermore, for multi-break structures, it cannot distinguish the action moments of different breaks within the same phase. Third, there is the detection method based on offline-to-online conversion and estimation. This method uses the displacement-time curve and the instantaneous opening and closing time measured offline, combined with the online displacement curve, to estimate the online instantaneous opening and closing time. This method relies on offline data and cannot achieve true online monitoring. The stress state of the circuit breaker differs between offline and online states, leading to accumulated errors in the estimation results. Furthermore, it still requires the installation of displacement sensors, affecting the insulation performance of the equipment. Fourth, there is the detection method based on high-frequency signal injection. This method couples a high-frequency signal to one end of the moving and stationary contacts in the main circuit of the circuit breaker and decouples it at the other end for detection. The presence or absence of high-frequency signal conduction determines whether the contacts are in contact. This method requires additional high-frequency signal coupling and decoupling circuits, making the system complex and costly. It can only detect the contact state and cannot detect the instantaneous contact separation. Moreover, for multi-break structures, each phase needs to have its own independent coupling and decoupling circuit, making reuse impossible.

[0005] In summary, existing technical solutions all have their limitations: some cannot achieve non-invasive measurement, some cannot distinguish the action time of each break in a multi-break structure, some measurement accuracy is limited by signal processing methods and sensor installation locations, and some can only detect a single process (opening or closing) and cannot simultaneously meet the requirement of synchronous detection of opening and closing. Therefore, there is an urgent need for a new synchronous measurement method and system that can adapt to multi-break structures, has high accuracy and strong anti-interference capabilities, can be applied to both opening and closing operations, and is easy to implement in the field. Summary of the Invention

[0006] The purpose of this invention is to provide a method for measuring the synchronicity of opening and closing of multi-vacuum break switchgear. This method utilizes a non-invasive configuration where a high-voltage probe is connected across both ends of the multi-vacuum break switchgear under test, and a vibration sensor is installed on the side of the stationary contact cover of each vacuum interrupter. It also employs a processing method that simultaneously acquires arc voltage and vibration signals and extracts the exact moments of opening and / or closing of each vacuum break. This improves the accuracy of the synchronicity measurement of opening and closing of multi-vacuum break switchgear and solves the technical problems in the prior art where the sealed structure of the equipment prevents direct measurement of each break, and where the accuracy of single signal detection is low and it is difficult to distinguish the timing of each break's action.

[0007] To address the aforementioned technical problems, a first aspect of this invention provides a method for measuring the synchronicity of opening and closing of a multi-vacuum break switchgear. This method is based on a multi-vacuum break switchgear synchronicity measurement system, which includes at least a power supply module, a control module, a data acquisition and measurement module, and a post-processing module. The data acquisition and measurement module includes a high-voltage probe and several vibration sensors. The high-voltage probe is connected across the two ends of the multi-vacuum break switchgear under test, and the vibration sensors are respectively installed on the side of the stationary contact cover of each vacuum interrupter chamber. The measurement method includes the following steps: The control module controls the power module to supply power to the multi-vacuum circuit breaker under test, and controls the multi-vacuum circuit breaker under test to perform opening and / or closing operations. The acquisition and measurement module synchronously acquires the arc voltage signal and vibration signal generated during the opening and / or closing operation to obtain the raw signal data. The post-processing module processes the original signal data to extract the moment of opening and / or closing of each vacuum break, and obtains the measurement results of the synchronicity of opening and closing of the multi-vacuum break switchgear based on the moment of opening and / or closing.

[0008] Further, the post-processing module processes the original signal data to extract the instantaneous opening and / or instantaneous closing time of each vacuum break, and obtains the measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear based on the instantaneous opening and / or instantaneous closing time, including: The arc voltage signal and vibration signal in the original signal data are respectively identified to obtain the arc voltage step feature point and the corresponding candidate opening time of each vacuum break during the opening process, and to obtain the vibration impact feature point and the corresponding candidate vibration time of each vacuum break during the opening and / or closing process. Based on the candidate opening time and the candidate vibration time of each vacuum break, the moment when each vacuum break is opened is obtained, and based on the candidate vibration time of each vacuum break, the moment when each vacuum break is closed is obtained. The opening time difference between different vacuum breaks is calculated based on the moment when each vacuum break just opens, and the closing time difference between different vacuum breaks is calculated based on the moment when each vacuum break just closes, thus obtaining the measurement results of the synchronicity of opening and closing of multi-vacuum-break switchgear.

[0009] Further, feature identification is performed on the arc voltage signal in the original signal data, including: The arc voltage signal in the original signal data is subjected to low-pass filtering and DC bias elimination processing to obtain the preprocessed arc voltage signal. Calculate the rate of change of the preprocessed arc voltage signal, and mark the signal interval in which the rate of change continuously exceeds a preset slope threshold as the arc voltage step start region; Within the arc voltage step start region, the position where the change in the rate of change exceeds a preset inflection point threshold is identified, and the corresponding time point is taken as the occurrence time of the arc voltage step feature point, and the occurrence time of the arc voltage step feature point is taken as the candidate opening time.

[0010] Further, feature identification is performed on the vibration signals in the original signal data, including: The vibration signal in the original signal data is subjected to bandpass filtering to obtain the preprocessed vibration signal; Envelope extraction is performed on the preprocessed vibration signal to obtain an envelope curve reflecting the change of vibration energy over time; On the envelope curve, identify impact peaks whose amplitude exceeds a preset background noise threshold. The time corresponding to the position where the amplitude of the impact peak first reaches a preset proportion of the impact peak amplitude during the rising edge is taken as the vibration impact feature point, and the time corresponding to the vibration impact feature point is taken as the candidate vibration moment.

[0011] Further, the step of identifying impact peaks with amplitudes exceeding a preset background noise threshold on the envelope curve, and using the time corresponding to the position where the amplitude of the rising edge of the impact peak first reaches a preset proportion of the impact peak amplitude as the vibration impact feature point, includes: After identifying the impact peak value with an amplitude exceeding a preset background noise threshold on the envelope curve, the rising edge interval of the impact peak value is determined. Within the rising edge interval, the trajectory of the amplitude change from the rising starting point to the peak impact is calculated, and the time corresponding to the position where the amplitude first reaches a preset proportion of the peak impact amplitude is taken as the vibration impact feature point.

[0012] Furthermore, controlling the multi-vacuum-break switchgear under test to perform opening and / or closing operations includes: When the circuit breaker trips, the control module sends a trigger signal according to a preset timing parameter, including: sending a trigger signal to the operating mechanism of the first vacuum break and the acquisition and measurement module at a first moment; sending a trigger signal to the operating mechanism of the second vacuum break after a first preset delay; and sending a trigger signal to the thyristor in the power supply module after a second preset delay to turn on the test circuit current. When the closing operation is performed, the control module sends a trigger signal according to the preset timing parameters, including: sending a trigger signal to the thyristor in the power module at a second moment; and after a third preset delay, simultaneously sending a closing trigger signal to the operating mechanism of all vacuum breaks.

[0013] Furthermore, before controlling the multi-vacuum-break switchgear under test to perform opening and / or closing operations, the method further includes: The inherent opening time of each vacuum break is measured separately to obtain the inherent opening time of each vacuum break. The timing parameters of the control module are set according to the inherent opening time of each vacuum break, so that the timing at which the control module sends a trigger signal to the operating mechanism of each vacuum break matches the inherent opening time of that vacuum break.

[0014] Furthermore, the multi-vacuum break switch device under test is a three-phase multi-vacuum break switch device, and the three-phase multi-vacuum break switch device shares one of the acquisition and measurement modules; The method of synchronously acquiring arc voltage signals and vibration signals generated during the opening and / or closing operations through the acquisition and measurement module includes: The acquisition and measurement module is sequentially connected to the multi-vacuum circuit breaker of the current phase to be tested, and the opening and / or closing tests are performed on each phase to obtain the opening and closing synchronicity data of each phase. The measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear obtained based on the instantaneous opening and / or instantaneous closing times include: The opening and / or closing time differences of the corresponding vacuum breaks between different phases are calculated based on the opening and / or closing times of each phase to obtain the measurement results of the opening and closing synchronicity of the three-phase multi-vacuum-break switchgear.

[0015] Furthermore, the control module includes a main control unit operation control platform and a main controller; The main controller generates trigger signals based on the control commands sent by the main control unit operation control platform to control the switching of the power module, the operation of the operating mechanism of the multi-vacuum-break switchgear under test, and the signal acquisition timing of the acquisition and measurement module.

[0016] Furthermore, the vibration sensor is mounted on the rigid housing on the side of the stationary contact cover plate.

[0017] Accordingly, a second aspect of the present invention provides an electronic device, including: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform the above-described method for measuring the opening and closing synchronism of a multi-vacuum-break switchgear.

[0018] Accordingly, a third aspect of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-described method for measuring the synchronicity of opening and closing of a multi-vacuum-break switchgear.

[0019] The above-described technical solutions of the embodiments of the present invention have the following beneficial technical effects: 1. By using a non-invasive sensor configuration where a high-voltage probe is connected across both ends of the multi-vacuum break switchgear under test and vibration sensors are installed on the side of the stationary contact cover of each vacuum interrupter, effective acquisition of internal action information of multiple breaks is achieved without damaging the equipment's sealing structure or affecting internal insulation. This solves the technical problem that the electrical parameters of each break cannot be directly measured because the vacuum interrupter is sealed inside a metal shell, and provides a feasible technical approach for measuring the opening and closing synchronicity of multi-vacuum break switchgear. 2. By synchronously acquiring arc voltage signals and vibration signals during the opening and closing operations, and fusing them based on the complementary characteristics of the two signals, the advantages of the arc voltage signal having obvious step characteristics during the opening process and the vibration signal having prominent impact characteristics during the closing process are fully utilized. This overcomes the shortcomings of single signal detection methods, such as difficulty in taking into account both the opening and closing processes, susceptibility to environmental interference, and limited accuracy, and significantly improves the accuracy and reliability of synchronous measurement. 3. By performing rate-of-change analysis and inflection point identification on arc voltage signals, and extracting the envelope of vibration signals and locating the rising edge at a preset ratio, a high-precision feature recognition method is developed. This effectively eliminates the influence of signal disturbance, background noise, and mechanical dispersion on feature point interpretation, and achieves precise positioning of the moment when each vacuum break is just opened and closed. This provides a reliable data foundation for accurately judging the synchronicity of opening and closing of multi-vacuum break switchgear, thereby ensuring the breaking capacity and operational safety of the equipment. Attached Figure Description

[0020] Figure 1 This is a flowchart of the method for measuring the opening and closing synchronicity of multi-vacuum-break switchgear provided in this embodiment of the invention; Figure 2 This is a schematic diagram illustrating the principle of testing the inherent opening time of a vacuum break according to an embodiment of the present invention. Figure 3 A schematic diagram of the opening and closing synchronization test of a single-phase dual-vacuum circuit breaker provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of a three-phase dual-vacuum circuit breaker device for synchronicity testing of opening and closing, provided as an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0022] The measurement method in this invention is based on an improvement of the following multi-vacuum break switchgear opening and closing synchronism measurement system. The system includes at least: a power supply module, a control module, an acquisition and measurement module, and a post-processing module. The acquisition and measurement module includes a high-voltage probe and several vibration sensors. The high-voltage probe is connected across the two ends of the multi-vacuum break switchgear under test, and several vibration sensors are respectively installed on the side of the stationary contact cover of each vacuum interrupter.

[0023] The following example uses a multi-vacuum circuit breaker in a 220kV substation within a real-world power system operation scenario. When periodic synchronization testing of opening and closing is required, the measurement system of this invention is deployed at the site of the device under test. First, the high-voltage probe in the acquisition and measurement module is connected across the two ends of the multi-vacuum circuit breaker under test, i.e., between the incoming and outgoing terminals. This probe can employ a high-impedance design to sense the voltage changes across the entire series circuit without affecting the main circuit insulation and normal operation. Simultaneously, multiple vibration sensors are installed on the rigid housing of the cover plate on the stationary contact side of each vacuum interrupter. This location, close to the contact system, minimizes the vibration propagation path and reduces energy attenuation. The vibration sensors can be piezoelectric accelerometers with wide frequency response characteristics, installed securely without damaging the equipment's sealing structure via magnetic attraction or adhesive bonding. Subsequently, the control module sends commands to the power module according to a preset timing sequence, causing it to output a current that meets the test requirements, while simultaneously controlling the device under test to perform opening or closing operations. During operation, the acquisition and measurement module simultaneously acquires the arc voltage signal output by the high-voltage probe and the vibration signals output by all vibration sensors, and transmits these raw signal data to the post-processing module in real time. By analyzing these signals, the post-processing module can decouple the step change of arc generation and extinction from the overall voltage waveform, extract the impact characteristics generated by contact impact from each vibration waveform, and accurately calculate the instantaneous opening or closing moment of each vacuum break, ultimately obtaining a quantitative result of the synchronicity of the entire equipment's opening and closing. Specifically, the instantaneous opening moment refers to the instant the moving contact and stationary contact just separate during the opening process, corresponding to the starting point of the step change in the arc voltage signal; the instantaneous closing moment refers to the instant the moving contact and stationary contact just come into contact during the closing process, corresponding to the point where the first impact characteristic appears in the vibration signal.

[0024] This measurement method, based on the collaboration of a bridging high-voltage probe and a multi-point vibration sensor, enables non-contact and precise sensing of the action time of each break in a multi-break switchgear without intruding into the equipment or altering the original insulation structure. It effectively solves the industry problem that the electrical parameters of each break cannot be directly measured due to the sealing of the vacuum interrupter, providing reliable technical support for the condition monitoring and fault diagnosis of high-voltage switchgear.

[0025] Furthermore, the control module includes a main control unit operation control platform and a main controller. Based on the control commands sent by the main control unit operation control platform, the main controller generates trigger signals to control the switching of the power supply module, the operation of the operating mechanism of the multi-vacuum-break switchgear under test, and the signal acquisition timing of the acquisition and measurement module.

[0026] In the aforementioned substation testing scenario, staff set various operating parameters for the opening and closing test using the main control unit's operation control platform. This platform is typically deployed in a safe area on-site or integrated into a portable industrial computer. It can establish a communication connection with the main controller on the field side via fiber optic cable to achieve electrical isolation between the high and low voltage sides. When the test command is issued, the main control unit's operation control platform sends control commands, including information such as power switching timing, operating mechanism action timing, and signal acquisition window, to the main controller in the form of a serial data stream. The main controller uses an industrial-grade microcontroller as its core processor. Upon receiving instructions, it generates multiple precise and synchronized trigger signals in parallel based on its internally programmed timing logic. The first trigger signal drives the switching devices in the power supply module, controlling the injection of test current into the main circuit at a predetermined time. The second trigger signal, after isolation and amplification, drives the operating mechanism of the multi-vacuum-break switchgear under test, realizing the mechanical action of opening or closing the circuit. The third trigger signal directly acts on the digital acquisition card in the acquisition and measurement module, precisely controlling the timing of its sampling start, ensuring that the high-voltage probe and vibration sensor can completely record the data from before the mechanism's action to after the arc is extinguished. During this process, the main controller achieves electrical isolation between the trigger signals and the external power circuits through optocouplers and uses an independent hardware timer to generate microsecond-level timing pulses, thereby eliminating timing jitter caused by software interrupt response delays and ensuring that power switching, mechanism action, and data acquisition strictly adhere to the preset timing coordination relationship.

[0027] Furthermore, the vibration sensor is mounted on the rigid housing on the side of the stationary contact cover.

[0028] This location was chosen based on a thorough analysis of the vibration propagation path. When the multi-vacuum circuit breaker under test performs opening or closing operations, a strong mechanical impact is generated at the moment of separation or contact between the moving and stationary contacts. This impact force acts directly on the end of the stationary contact and is transmitted to the stationary contact cover plate at the top of the arc-extinguishing chamber through the stationary contact rod. Because the stationary contact cover plate is rigidly connected to the arc-extinguishing chamber shell, and the cover plate itself is made of metal, the mechanical wave propagation distance is the shortest and the energy attenuation is minimal along this path. It also avoids signal distortion introduced by flexible components such as bellows or insulating rods. In actual installation, the operator can select a suitable sensor fixing method according to the structure of the arc-extinguishing chamber. For example, for arc-extinguishing chambers with flat end covers, a magnetic base can be used to attach the sensor to the cover plate surface; for compact structures, threaded connections or quick-drying adhesive can be used to ensure rigid coupling between the sensor and the shell. Each vibration sensor is connected to the digital acquisition card in the acquisition and measurement module via a shielded cable. The cable employs a double-shielded design and is grounded at the sensor end to suppress common-mode interference introduced by power frequency electric and magnetic fields. When the equipment operates, the sensor mounted on each break cover can independently sense the vibration waveform generated by the impact of the break contact. Due to the sensor's proximity to the vibration source and reliable coupling, the acquired vibration signal has the characteristics of a steep rise edge, high signal-to-noise ratio, and clear features, accurately reflecting the actual action moment of the break contact. By independently acquiring and synchronously comparing the signals from multiple vibration sensors, the sequence and time difference of each vacuum break during the opening or closing process can be accurately distinguished. This installation method, which directly deploys the vibration sensors on the rigid housing on the side of the stationary contact cover, fundamentally solves the signal ambiguity problem caused by the sensor's distance from the vibration source in traditional vibration detection methods. It significantly improves the time correspondence between the vibration signal and the contact action, providing high-quality raw data support for the subsequent accurate extraction of the exact moments of each break's opening and closing from the vibration waveform.

[0029] Please refer to Figure 1 In conjunction with the above-mentioned hardware improvements, the first aspect of this invention provides a method for measuring the synchronicity of opening and closing of a multi-vacuum-break switchgear. The measurement method is implemented based on a multi-vacuum-break switchgear opening and closing synchronicity measurement system and includes the following steps: In step S100, the control module controls the power supply module to supply power to the multi-vacuum circuit breaker under test, and controls the multi-vacuum circuit breaker under test to perform opening and / or closing operations.

[0030] When performing a synchronous test on a 252kV multi-vacuum circuit breaker at a substation, the main control unit in the control module first sets the test mode to either a tripping or closing test and issues a start command. This start command is transmitted via fiber optic cable to the main controller on the field side. The main controller, based on preset timing logic, sends a switching signal to the power supply module, causing it to output a power frequency current or DC current that meets the test requirements to the main circuit of the device under test. Simultaneously, the main controller sends a trigger pulse to the operating mechanism of the device under test. Upon energization, the operating mechanism drives the transmission system, causing the moving contacts of each vacuum interrupter to perform the tripping or closing mechanical movement. Throughout the process, the control module precisely coordinates the timing of power supply and mechanism action, ensuring that test current flows in the main circuit at the moment the contacts are about to separate or close, creating conditions for the subsequent generation of the arc voltage signal.

[0031] Step S200: The arc voltage signal and vibration signal generated during the opening and / or closing operation are synchronously acquired by the acquisition and measurement module to obtain the raw signal data.

[0032] While the switching equipment performs opening or closing operations, the data acquisition and measurement module begins operation. A high-voltage probe connected across the two ends of the multi-vacuum-break switchgear under test senses the voltage changes across the entire series of breaks in real time. When the moving contact separates from the stationary contact, an arc is generated, causing a step change in the voltage waveform; when the contact closes, the arc is extinguished, and the voltage waveform changes accordingly. The high-voltage probe attenuates the high-voltage signal and converts it into a low-voltage analog signal, which is then transmitted to the digital acquisition card via a shielded cable. Simultaneously, vibration sensors installed on the rigid housing of the stationary contact cover of each vacuum interrupter sense weak mechanical vibration waves at the moment of contact impact and convert them into charge or voltage signals, which are also conditioned and transmitted to the same digital acquisition card. The digital acquisition card performs synchronous analog-to-digital conversion on multiple signals at a preset high sampling rate (e.g., 200 kS / s per channel) to ensure that the arc voltage signal and the signals from each vibration sensor are strictly aligned on the time axis. After acquisition, the digitized waveform data from all channels are encapsulated into data frames with absolute time stamps, forming raw signal data files. These files are stored in the local cache of the acquisition and measurement module, ready for transmission to the post-processing module. Through multi-sensor collaboration and high-speed synchronous sampling, the transient changes in electrical and mechanical quantities during equipment operation are fully captured.

[0033] Step S300: The original signal data is processed by the post-processing module to extract the moment of opening and / or closing of each vacuum break, and the measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear are obtained based on the moment of opening and / or closing.

[0034] After acquiring the raw signal data from the acquisition and measurement module, the post-processing module initiates the data analysis process. First, it analyzes the arc voltage signal, identifying the step change points in the voltage waveform caused by the generation or extinction of the arc. These change points correspond to the instant the contacts just separate or just make contact, thus initially determining the candidate moments for the instantaneous separation or closing of each vacuum break. Simultaneously, it performs envelope analysis and feature point identification on the signals from each vibration sensor, extracting the arrival time of the first strong shock wave generated by the contact impact from the vibration waveform. This moment also corresponds to the mechanical event of contact action. The post-processing module correlates and compares the arc voltage feature points and vibration feature points of the same break, eliminating misjudgments caused by interference through mutual verification, ultimately accurately locating the true moments of separation and closing for each vacuum break. Subsequently, using a specific break as a reference, it calculates the time difference between other breaks and this reference break, obtaining the opening and closing time differences for each break within the same phase. If the device under test is a three-phase structure, the time differences between different phases can be further calculated. By comparing these time differences with a preset synchronicity threshold, it is possible to determine whether the opening and closing synchronicity of the multi-vacuum-break switchgear is qualified, and the measurement results are output in numerical or graphical form.

[0035] This invention utilizes a non-invasive acquisition system consisting of a high-voltage probe connected across both ends of the device under test and a vibration sensor installed on the side of the stationary contact cover of each arc-extinguishing chamber, along with a post-processing module for synchronous processing of arc voltage and vibration signals. This enables precise extraction of the exact moment of opening and closing of each break in a multi-vacuum-break switchgear under a sealed structure. It effectively solves the technical problems of low accuracy and difficulty in distinguishing the action moments of each break in single signal detection methods, significantly improving the accuracy and reliability of opening and closing synchronicity measurement, and providing strong support for the safe operation and condition-based maintenance of high-voltage switchgear.

[0036] Specifically, in step S300, the post-processing module processes the raw signal data, extracts the instantaneous opening and / or instantaneous closing time of each vacuum break, and obtains the measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear based on the instantaneous opening and / or instantaneous closing time, including: Step S310: Perform feature identification on the arc voltage signal and vibration signal in the original signal data respectively to obtain the arc voltage step feature point and the corresponding candidate opening time of each vacuum break during the opening process, and obtain the vibration impact feature point and the corresponding candidate vibration time of each vacuum break during the opening and / or closing process.

[0037] The post-processing module first separates the raw signal data by channel, obtaining one arc voltage waveform and multiple vibration waveforms. For the arc voltage signal, the source is a high-voltage probe connected across the two ends of the equipment, reflecting the voltage change across the entire series of multiple breaks. When an arc is generated during the opening process of a break, the voltage waveform exhibits a steep step-falling edge; after all breaks have opened, the voltage tends to stabilize. The post-processing module analyzes the first derivative or abrupt changes in the voltage waveform to identify the locations of these step changes. Each step point corresponds to the instant when an arc begins to ignite at a break, and is marked as an arc voltage step characteristic point. The time coordinate of this point is recorded as the candidate opening time for that break. For the vibration signals, the post-processing module processes the independent waveforms from the vibration sensors on the static contact cover side of each vacuum interrupter chamber. On each vibration waveform, when the moving contact and stationary contact of the corresponding break point collide (separation collision during opening or contact collision during closing), one or more impact pulse trains are formed. The arrival time of the first large-amplitude impact wave is highly correlated with the contact action time. The post-processing module extracts the starting point or peak point of the first obvious impact in each vibration waveform by setting an energy threshold or performing waveform envelope analysis. This is used as the vibration impact characteristic point, and the time coordinate of this point is recorded as the candidate vibration time of that break point. For the opening process, the vibration signal also exhibits impact characteristics, thus allowing the acquisition of candidate vibration times. For the closing process, the vibration signal is the primary source for obtaining candidate times.

[0038] Step S320: Based on the candidate opening time and candidate vibration time of each vacuum break, obtain the moment when each vacuum break is opened during opening; based on the candidate vibration time of each vacuum break, obtain the moment when each vacuum break is closed during closing.

[0039] The post-processing module performs correlation analysis and verification between the candidate opening time and the candidate vibration time for each vacuum break. For the opening operation, the arc voltage step feature point directly reflects the generation of the arc at the moment of contact separation, with clear physical meaning and high time resolution. Therefore, the candidate opening time is usually used as the main basis for determining the moment of instantaneous separation. At the same time, the candidate vibration time of the same break is used as an auxiliary verification. If the time difference between the two is within a preset reasonable range (e.g., tens to hundreds of microseconds), they corroborate each other, enhancing the reliability of the results. If the step point of a certain break is not obvious or cannot be identified due to interference with the arc voltage signal, the module automatically switches to use the candidate vibration time as a supplementary basis for the moment of instantaneous separation of that break. For the closing operation, since the arc voltage signal changes smoothly before the contacts close during the closing process, it is difficult to extract a clear step feature point. Therefore, the post-processing module directly uses the candidate vibration time of each break as its moment of instantaneous closing.

[0040] Step S330: Calculate the opening time difference between different vacuum breaks based on the opening time of each vacuum break, and calculate the closing time difference between different vacuum breaks based on the closing time of each vacuum break, to obtain the measurement results of the opening and closing synchronicity of the multi-vacuum-break switchgear.

[0041] After obtaining the exact opening and closing times of all vacuum breaks, the post-processing module uses the first break to activate as a reference to calculate the time difference between the opening and closing times of each of the other breaks and the reference opening time, forming a set of switching time difference data. Similarly, it calculates the time difference between the closing times of each break, forming closing time difference data. For three-phase multi-break structures, the time difference between corresponding breaks between phases can be further calculated. Subsequently, these time differences are compared item by item with the synchronization standard thresholds (such as those specified in national standards or equipment technical specifications) pre-stored in the system: if all time differences are less than or equal to the allowable value, the switching synchronization of the equipment is deemed qualified; if any time difference exceeds the threshold, it is deemed unqualified, and the specific break number and its time difference value are output. Finally, the post-processing module integrates the original waveform diagram, feature point marking diagram, list of the opening and closing times of each break, time difference calculation results, and synchronization judgment conclusion into a complete test report for maintenance personnel to assess the equipment status.

[0042] Through the refined processing flow of step-by-step feature recognition, multi-source fusion, and time difference calculation, the present invention can accurately extract the moment of opening and closing of each vacuum break from the original signal data, effectively overcoming the defects of single signal recognition being susceptible to interference or having indistinct features, significantly improving the accuracy and reliability of the synchronicity measurement of opening and closing of multi-break switchgear, and providing a solid data foundation for the condition assessment and preventive maintenance of high-voltage switchgear.

[0043] Further, step S310 involves feature identification of the arc voltage signal in the original signal data, including: Step S311a: Perform low-pass filtering and DC bias elimination processing on the arc voltage signal in the original signal data to obtain the preprocessed arc voltage signal.

[0044] When the raw arc voltage signal acquired by the high-voltage probe across the device under test is sent to the post-processing module, in addition to the step changes reflecting the contact separation and closure process, the signal inevitably contains high-frequency interference components from spatial electromagnetic radiation, power supply ripple, and sensor noise. Furthermore, due to residual charge or amplifier zero-point drift in the measurement circuit, the signal baseline often deviates from zero potential. To eliminate these adverse factors, the post-processing module first processes the raw signal using a digital low-pass filter. This filter is typically designed as a Butterworth or elliptic filter with a flat passband and a steep transition band. Its cutoff frequency is set according to the dominant frequency range of the arc voltage signal (usually several kHz to tens of kHz), effectively suppressing noise components above this frequency while preserving the key step characteristics of the signal. Subsequently, the module calculates the average value of the signal in a stable interval before contact action, uses this as a DC bias, and subtracts it from the entire signal, bringing the signal baseline back to near zero. After these two pre-processing steps, the resulting arc voltage signal waveform is smooth and the baseline is zero.

[0045] Step S311b: Calculate the rate of change of the preprocessed arc voltage signal, and mark the signal intervals in which the rate of change continuously exceeds the preset slope threshold as the arc voltage step start region.

[0046] After obtaining the preprocessed arc voltage signal, the post-processing module calculates the rate of change of the signal at each sampling point, i.e., the first derivative, using a numerical difference algorithm. This rate of change reflects the drastic change in voltage over time. During the circuit breaker tripping process, when the contacts of a vacuum break begin to separate and generate an arc, the voltage waveform exhibits a steep falling edge, corresponding to a negative spike in the rate of change. The module presets a reasonable slope threshold, typically determined based on extensive historical test data or typical waveform characteristics of the equipment, to distinguish between normal fluctuations and genuine step events. The module scans the entire signal sequence point by point, marking the interval where the absolute value of the rate of change of multiple consecutive sampling points exceeds the slope threshold as the "arc voltage step start region." Since the actual waveform's rising or falling edge may be accompanied by slight jitter, using the criterion of continuous exceedance of the threshold rather than single-point exceedance effectively avoids misjudging isolated noise spikes as step start points, improving the robustness of feature region localization.

[0047] Step S311c: In the arc voltage step start region, identify the position where the change in the rate of change exceeds the preset inflection point threshold, take the corresponding time point as the occurrence time of the arc voltage step feature point, and take the occurrence time of the arc voltage step feature point as the candidate opening time.

[0048] After identifying the starting region of each step voltage change, the post-processing module further focuses on the local details within that region, aiming to precisely locate the steepest point on the step waveform—that is, the inflection point where the rate of change is largest. To this end, the module calculates the second-order derivative of the rate of change within that region to describe the rate of change itself. A threshold for inflection points is preset. When the rate of change at a point exceeds this threshold, and the sign of the rate of change reverses before and after that point (e.g., from negative to positive or from positive to negative), that point is identified as the true inflection point of the step waveform, i.e., the arc voltage step characteristic point. This characteristic point corresponds to the moment when the voltage change is most drastic at the start or end of the arc, physically coinciding closely with the moment the contacts just open or close. The module extracts the time coordinate of this characteristic point as the candidate opening time of the vacuum break. This two-step identification strategy of "coarse positioning followed by fine correction" effectively overcomes the influence of potential smooth areas or pre-breakdown disturbances at the waveform leading edge on the time interpretation, significantly improving the accuracy and consistency of the candidate opening time.

[0049] Further, step S310 involves feature identification of the vibration signal in the original signal data, including: Step S312a: Bandpass filtering is performed on the vibration signal in the original signal data to obtain the preprocessed vibration signal.

[0050] When vibration sensors installed on the rigid housing of the stationary contact cover of each vacuum interrupter convert the mechanical waves generated by the contact impact into electrical signals and send them to the post-processing module, these raw vibration signals contain not only the effective impact component reflecting the moment of contact action, but also mixed background power frequency vibrations, low-frequency disturbances caused by other equipment operations, and high-frequency interference introduced by the sensor's own electronic noise or electromagnetic coupling. To extract the mechanical impact component truly relevant to contact action from this complex signal background, the post-processing module first performs bandpass filtering on each vibration signal. The passband range of this filter is determined based on extensive measured data and theoretical analysis, typically covering the frequency band from several hundred hertz to several thousand hertz. This frequency band concentrates the main energy of the mechanical waves generated by the contact impact, while slow fluctuations below this band and spike noise above it are effectively suppressed. The filter can be implemented using a finite impulse response filter with linear phase characteristics or a computationally efficient infinite impulse response filter, ensuring that the filtered waveform is not distorted or phase-shifted. After bandpass filtering, the background interference in the obtained vibration signal is significantly reduced, and the impact pulse generated by the contact impact is more prominent, providing high-quality input data for subsequent envelope extraction and feature point recognition.

[0051] Step S312b: Extract the envelope of the preprocessed vibration signal to obtain an envelope curve that reflects the change of vibration energy over time.

[0052] Even after bandpass filtering, the vibration signal still exhibits a rapidly oscillating, alternating positive and negative waveform, making it difficult to directly identify the precise moment of contact action. This is because there is an uncertain time offset between the peak point of the oscillation waveform and the initial moment of contact impact. To address this issue, the post-processing module performs envelope extraction on the preprocessed vibration signal. Methods such as Hilbert transform or absolute value low-pass filtering are typically used to convert the high-frequency oscillation signal into a smooth envelope curve reflecting the change of vibration energy over time. The physical meaning of this envelope curve lies in characterizing the instantaneous amplitude of the mechanical impact energy. When the contact impacts, the envelope curve exhibits a steep rising edge, which then gradually decays. Through this transformation, the originally complex oscillation waveform is simplified into a straightforward energy pulse, transforming the problem of identifying the contact action moment into the problem of detecting the rising edge of the envelope curve, significantly improving the reliability and accuracy of feature extraction.

[0053] Step S312c: Identify the impact peak value that exceeds the preset background noise threshold on the envelope curve, take the time corresponding to the position where the amplitude first reaches the preset proportion of the impact peak value in the rising edge of the impact peak value as the vibration impact feature point, and take the time corresponding to the vibration impact feature point as the candidate vibration time.

[0054] After obtaining the envelope curve reflecting the change in vibration energy, the post-processing module first statistically analyzes the envelope amplitude level during the inactive period at the beginning of the signal. Based on this, a background noise threshold slightly higher than the background noise is set to distinguish between actual contact impact events and residual noise fluctuations. The module scans the envelope curve point by point, identifying local maxima where the amplitude exceeds the threshold, marking them as impact peaks. Each peak corresponds to a significant mechanical impact event. For the opening or closing process, the first impact peak usually corresponds to the moment when the moving contact and stationary contact first separate or contact. However, the impact peak itself is not the precise moment of contact action, because it takes time for energy to transfer from the impact point to the sensor and accumulate to the peak value; the peak point lags behind the actual contact action moment. To solve this problem, the module further analyzes the rising edge of each impact peak, calculating the gradual increase in amplitude from the starting point of the rising edge, and locating the position where the amplitude first reaches a preset proportion (e.g., 20% or 30%) of the impact peak amplitude. This location is in the early stage of the rising edge, when energy is just beginning to accumulate, closest to the initial moment of contact impact, while avoiding potential noise interference at the starting point of the rising edge. The module extracts the time coordinate corresponding to this location as the occurrence time of this vibration impact characteristic point, and uses this as a candidate vibration moment for the vacuum fracture. This rising edge proportional point positioning method effectively eliminates the time lag error caused by the vibration propagation path and sensor response, significantly improving the accuracy of the vibration signal in characterizing the contact action moment.

[0055] By performing the above three-stage processing on the vibration signal—bandpass filtering to remove interference, envelope extraction to convert the oscillation signal into an energy curve, and precise location of the impact feature point based on the background noise threshold and the rising edge ratio—this invention achieves high-precision identification of vibration impact feature points during the opening and closing process of multi-vacuum-break switchgear. It effectively overcomes the influence of sensor installation location, vibration propagation path, and environmental interference on time interpretation, providing accurate and reliable candidate vibration moments for subsequent determination of the moment of opening and closing, and further improving the anti-interference capability and measurement accuracy of the overall synchronicity measurement method.

[0056] Furthermore, step S312c, which identifies impact peaks on the envelope curve whose amplitudes exceed a preset background noise threshold, and uses the time corresponding to the position where the amplitude first reaches a preset proportion of the impact peak amplitude during the rising edge of the impact peak as the vibration impact feature point, includes: Step S312c1: After identifying the impact peak value with an amplitude exceeding the preset background noise threshold on the envelope curve, determine the rising edge interval of the impact peak value.

[0057] When conducting opening and closing tests on multi-vacuum-break switchgear at substation sites, the post-processing module first identifies several impact peaks from the envelope curve of the vibration signal based on a preset background noise threshold. These peaks correspond to the energy pulses generated by contact impact. However, knowing only the time of peak occurrence is insufficient to accurately determine the contact action time, as the peak point lags behind the actual impact start point. Therefore, the module further analyzes the waveform morphology of each identified impact peak to determine its corresponding rising edge interval. Specifically, the module traces back along the time axis from the location of the impact peak, searching for the position where the envelope curve amplitude first drops to near the background noise level or shows a clear inflection point, marking this position as the starting point of the rising edge; simultaneously, the impact peak position is used as the ending point of the rising edge. The time interval between the starting and ending points is the rising edge interval of that impact peak. This interval fully covers the process from the initial appearance of impact energy to its maximum accumulation, providing a clear search range for subsequent precise positioning of the contact action time on the rising edge. By pre-determining the rising edge interval, the module avoids blindly searching along the entire time axis, improving processing efficiency.

[0058] Step S312c2: Within the rising edge interval, calculate the trajectory of the amplitude change from the rising starting point to the peak impact value, and take the time corresponding to the position where the amplitude first reaches the preset proportion of the peak impact amplitude as the vibration impact characteristic point.

[0059] After determining the rising edge range of each impact peak, the post-processing module performs a detailed analysis of the envelope curve within that range. Because there is a physical propagation process from the contact impact to the transfer of vibration energy to the sensor and its reflection as an increase in envelope amplitude, the starting point of the rising edge, although close to the impact moment, is often difficult to pinpoint precisely due to background noise or weak pre-motion; while the peak point, although obvious, lags behind the actual impact moment. To find the balance point that best represents the impact instant, the module employs a proportional positioning strategy. First, the amplitude of the impact peak is calculated as a baseline value, reflecting the maximum energy intensity of the impact. Then, the module scans the envelope curve point by point from the rising edge starting point towards the peak, calculating the percentage of the current amplitude relative to the baseline value. When the amplitude first reaches a preset ratio (e.g., 20%), this point is considered to correspond to the critical moment when the impact energy has just been established and is sufficient for reliable detection. This moment avoids the noise interference area at the rising edge starting point and is significantly earlier than the peak point, thus being closest to the actual contact action instant. The module extracts the time coordinate corresponding to this point as the occurrence time of the vibration impact characteristic point. By using this precise positioning method based on the rising edge proportional point, the present invention achieves high-precision extraction of the contact action moment in the vibration signal, effectively compensating for the time delay error caused by the vibration propagation path and sensor response.

[0060] Through the two-step processing described above—identifying the impact peak, determining the rising edge interval, and precisely locating the rising edge preset ratio point—the present invention achieves high-precision positioning of vibration impact feature points during the opening and closing process of multi-vacuum-break switchgear. This effectively overcomes the influence of sensor installation position, vibration propagation path, and environmental interference on time interpretation, and significantly improves the accuracy of vibration signal characterization of contact action time.

[0061] Specifically, step S100, controlling the multi-vacuum-break switchgear under test to perform opening and / or closing operations, includes: Step S110: When performing the tripping operation, the control module sends a trigger signal according to preset timing parameters, including: at a first moment, sending a trigger signal to the operating mechanism of the first vacuum break and the acquisition and measurement module; after a first preset delay, sending a trigger signal to the operating mechanism of the second vacuum break; after a second preset delay, sending a trigger signal to the thyristor in the power supply module to turn on the test circuit current.

[0062] During a synchronicity test of the opening of a 252kV multi-vacuum-break switchgear with a double-break structure at a substation site, the control module executes precise trigger control according to pre-set timing parameters. First, at the initial moment, the main controller simultaneously generates two trigger pulses: the first pulse is sent to the operating mechanism of the first vacuum break, initiating its opening action; the second pulse is sent to the digital acquisition card in the acquisition and measurement module, putting it into a pre-trigger acquisition state and caching real-time data from the vibration sensor and high-voltage probe. Since the two vacuum breaks share a transmission system or have a mechanical linkage, but the actual separation time may differ due to manufacturing tolerances or lubrication conditions, the control module sends an independent trigger signal to the operating mechanism of the second vacuum break after a first preset delay. This ensures that the operating mechanisms of the two breaks can start sequentially within a preset time difference. This delay is based on the pre-measured difference in the inherent opening times of the two breaks, compensating for their differences in mechanical characteristics. After the second vacuum break is triggered, the control module sends a conduction trigger signal to the thyristor in the power module after a second preset delay, causing the test circuit current to be injected into the main circuit at the precise moment the contacts are about to separate. This second preset delay is calculated based on the average or maximum value of the inherent opening times of the two breaks, ensuring that all contacts have not yet separated before the current is turned on, thus enabling accurate recording of the step change in arc voltage at the moment of contact separation. Through this step-by-step, time-division, and compensated trigger control strategy, the system can simulate the physical process of multiple breaks connected in series under actual operating conditions, providing an accurate time reference for subsequent step point identification of the arc voltage signal.

[0063] Step S120: When performing the closing operation, the control module sends trigger signals according to preset timing parameters, including: sending trigger signals to the thyristors in the power supply module at a second moment; and simultaneously sending closing trigger signals to the operating mechanisms of all vacuum breaks after a third preset delay.

[0064] When performing a closing synchronization test on the same double-break switchgear, the control module employs a different timing logic than the opening logic. First, at the second moment, the main controller sends a conduction trigger signal to the thyristors in the power module, injecting test circuit current into the main circuit in advance. At this time, all breaks are still in the open state, and no current flows in the main circuit. The purpose of this advance power supply is to ensure that a stable test current exists in the main circuit at the instant the contacts close, thus allowing the timing of current establishment to help determine whether the contacts are reliably in contact. Subsequently, after a third preset delay, the control module simultaneously sends a closing trigger signal to the operating mechanisms of the first and second vacuum breaks, causing the moving contacts of both breaks to begin moving towards the stationary contacts. Since both breaks receive the closing command simultaneously, their mechanical movement starts at the theoretically identical time. However, due to differences in transmission mechanisms, changes in friction, and other factors, there may be a slight time difference in the actual contact moment. This time difference is the core objective of the closing synchronization measurement. During the closing process, since the current has been pre-established in the main circuit, when the contact of a certain break closes first, the main circuit of that phase immediately conducts current, and the high-voltage probe can detect the voltage drop. However, since the voltage characteristics during the closing process are not as obvious as the step during the opening process, the system mainly relies on vibration sensors to capture the shock waves generated by the impact of the contacts at each break. The actual closing moment of each break is determined by comparing the arrival time differences of signals from multiple vibration sensors. The control module adopts a timing design of energizing first and then simultaneously triggering the mechanism during the closing operation. This ensures that the current is in place before the contacts close and also ensures the consistency of the mechanical start-up time of each break, providing stable and controllable test conditions for the subsequent characteristic identification of vibration signals.

[0065] By employing differentiated timing control strategies for the opening and closing operations, this invention achieves precise simulation and synchronous signal acquisition of the opening and closing processes of multi-vacuum-break switchgear. In the opening operation, time-division triggering and delay compensation ensure that current is injected at the instant the contacts separate, creating conditions for accurate identification of the arc voltage step point. In the closing operation, the simultaneous triggering mechanism, which first energizes the switch and then simultaneously triggers it, ensures both the early establishment of current and the consistency of the mechanical start-up time of each break, providing a reliable benchmark for the comparative analysis of vibration signals. This timing control method, designed to address the differences in physical characteristics between the opening and closing processes, significantly improves the accuracy and repeatability of synchronization testing, laying a solid foundation for subsequent signal processing and feature extraction.

[0066] Furthermore, before controlling the multi-vacuum circuit breaker under test to perform opening and / or closing operations in step S100, the following steps are also included: Step S101: Measure the inherent opening time of each vacuum break to obtain the inherent opening time of each vacuum break.

[0067] Before conducting formal synchronization tests on the opening and closing of multi-vacuum-break switchgear, it is necessary to first measure the inherent opening time of each vacuum break that constitutes the equipment independently. Taking a 252kV double-break vacuum switchgear as an example, after the equipment is taken out of operation and safety isolation measures are taken, the two vacuum interrupters are tested separately. For the first vacuum break, it is connected to a dedicated single-break test circuit, which includes a power supply module, a control module, and a high-voltage probe in the acquisition and measurement module. The control module sends a tripping trigger signal to the operating mechanism of the break while simultaneously starting a timer and sending a conduction signal to the thyristor in the power supply module, so that the test current is injected into the break circuit. When the moving contact of the break separates from the stationary contact and generates an arc, the high-voltage probe connected across the two ends of the break detects a step change in the arc voltage. The time corresponding to this change point is the actual tripping time of the break. The control module records the time interval from the issuance of the trigger signal to the occurrence of the arc voltage step point. This time interval is the inherent opening time of the vacuum break. Because the mechanical actions of vacuum switches are somewhat variable, a single measurement may not be sufficient to represent their true characteristics. Therefore, multiple tripping operations were performed on the break point to obtain a set of inherent tripping time measurements. Using the same method and steps, the inherent tripping time of the second vacuum break point was measured independently, also obtaining multiple measurement results. Finally, the multiple measurements for each vacuum break point were statistically averaged to obtain a precise and stable inherent tripping time for each break point. This preliminary measurement process fully considers the individual differences of each break point in terms of machining, assembly processes, and lubrication conditions, providing accurate basic data for setting timing parameters in subsequent synchronous tests.

[0068] Step S102: Set the timing parameters of the control module according to the inherent opening time of each vacuum break, so that the timing of the control module sending the trigger signal to the operating mechanism of each vacuum break matches the inherent opening time of that vacuum break.

[0069] After obtaining the precise inherent opening time of each vacuum break, the operators input this data into the main control unit operation control platform in the control module. The platform automatically calculates or manually sets the timing parameters required for the synchronization test. Taking a dual-break opening test as an example, assume the inherent opening time of the first vacuum break is T1, and the inherent opening time of the second vacuum break is T2, with T1 less than T2, meaning the first break operates faster and the second break operates slower. To ensure that the two breaks separate as simultaneously as possible during the actual opening process, the control module needs to initiate the slower second break earlier and delay the faster first break. Specifically, the time when the trigger signal is sent to the second vacuum break is set earlier than the time when the trigger signal is sent to the first vacuum break; the time difference between the two is the difference between T2 and T1. Through this compensation mechanism, although the two breaks receive the trigger signal at different times, the final contact separation time tends to be consistent. This matching process applies not only to the opening test but also affects the setting of the second preset delay for sending the conduction signal to the thyristor during the opening test. This delay must ensure that current conduction occurs before all breaks have been activated but not yet separated. For the closing test, although the closing process does not involve the direct application of the inherent opening time, the closing trigger timing can still be optimized and adjusted based on the differences in mechanical characteristics of each break reflected by the inherent opening time. For example, it can ensure that each break receives the closing trigger signal simultaneously, so as to accurately capture the slight differences in the impact time of each break in the vibration signal. Through this personalized setting of timing parameters based on the measured inherent opening time, the control module achieves refined adaptive control of the opening and closing process of multi-vacuum-break switchgear, effectively eliminating systematic errors introduced by the differences in mechanical characteristics of each break.

[0070] By independently measuring the inherent opening time of each vacuum break before the formal synchronicity test, and dynamically setting the timing parameters of the control module based on the actual measurement results, this invention achieves personalized adaptive control of the opening and closing process of multi-vacuum break switchgear. It effectively compensates for the inconsistency in mechanical characteristics caused by factors such as manufacturing tolerances, assembly differences, and aging during operation, enabling the synchronicity test to be carried out under the condition that the action time of each break tends to be ideally synchronized. This significantly improves the accuracy and repeatability of the synchronicity measurement results, laying a solid foundation for subsequent multi-break collaborative characteristic analysis and equipment condition assessment.

[0071] In one embodiment of the present invention, the multi-vacuum break switch device under test is a three-phase multi-vacuum break switch device, and the three-phase multi-vacuum break switch devices share a common acquisition and measurement module.

[0072] In one specific embodiment of the present invention, the device under test is a 252kV three-phase multi-vacuum break switchgear. Each phase contains two vacuum breaks connected in series. The entire three-phase device shares the same acquisition and measurement module, which includes a high-voltage probe bridging the two ends of the phase under test and six vibration sensors respectively installed on the stationary contact cover side of each vacuum interrupter. During on-site testing, the operator first electrically connects the acquisition and measurement module to the A-phase multi-vacuum break switch of the device under test, that is, connects the high-voltage probe between the A-phase incoming and outgoing terminals, and installs two of the six vibration sensors respectively on the stationary contact cover side of the two interrupters of phase A. After the connection and installation are completed, the opening and closing tests of phase A are started through the control module. The acquisition and measurement module synchronously records the arc voltage signal and the vibration signal of the two breaks during the opening and closing process of phase A, obtaining the synchronicity data of opening and closing of phase A, including the exact opening and closing times of the two breaks in phase A and the time difference between them. After the A-phase test is completed, the staff disconnects the acquisition and measurement module from the A-phase and connects it to the B-phase multi-vacuum circuit breaker. The high-voltage probe is then connected across both ends of the B-phase circuit breaker, and the two corresponding vibration sensors are installed on the stationary contact cover plates of the two arc-extinguishing chambers of the B-phase circuit breaker. After ensuring the connection is correct, the B-phase test is started to obtain the phase-opening and closing synchronization data. Following the same steps, the C-phase test is finally completed, obtaining the phase-opening and closing synchronization data for the C-phase. Through this sequential connection and phase-by-phase testing method, a single acquisition and measurement module can complete the phase-opening and closing synchronization measurement of all six circuit breakers in the three-phase equipment. This avoids the hardware redundancy and increased cost associated with configuring a complete set of sensors and acquisition channels for each phase. Furthermore, since all phase tests use the same set of sensors and acquisition channels, measurement errors introduced by differences in gain, bias, and frequency response between different channels are eliminated, ensuring the comparability of data between each phase.

[0073] Accordingly, the arc voltage signal and vibration signal generated during the opening and / or closing operations are synchronously acquired through the acquisition and measurement module, including: sequentially connecting the acquisition and measurement module to the multi-vacuum break switch of the current phase under test, performing opening and / or closing tests on each phase respectively, and obtaining the opening and closing synchronicity data of each phase. Correspondingly, the measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear are obtained based on the moment of opening and / or the moment of closing, including: calculating the opening time difference and / or closing time difference between the corresponding vacuum breaks of different phases based on the moment of opening and / or the moment of closing of each phase, and obtaining the measurement results of the opening and closing synchronicity of the three-phase multi-vacuum break switchgear.

[0074] After obtaining the synchronization data for the opening and closing of phases A, B, and C, the post-processing module performs phase-to-phase synchronization analysis based on this data. Taking the opening process as an example, the post-processing module extracts the exact opening times of the first and second breaks in phase A from the phase A data, the exact opening times of the two breaks in phase B from the phase B data, and the exact opening times of the two breaks in phase C from the phase C data. Then, using the exact opening time of the first break in phase A as a reference, the time difference between the exact opening times of the first breaks in phase B and phase A, and the time difference between the exact opening times of the first breaks in phase C and phase A, are calculated; similarly, the time difference between the exact opening times of the second breaks in each phase is calculated. These time differences are compared with the allowable values ​​for phase-to-phase opening asynchrony specified in national standards or equipment technical specifications. If all time differences are within the allowable range, the three-phase equipment is deemed to have qualified opening synchronization; if any phase-to-phase time difference exceeds the allowable value, it is deemed unqualified, and the specific phase and break location of the out-of-tolerance device are output. For the closing process, the same method is used to calculate the phase-to-phase time difference between the moments when each phase's disconnection point just closes, and this difference is compared with the allowable value for closing asynchrony to obtain a conclusion on the closing synchronism. Through this layered calculation and comparison strategy, which prioritizes intra-phase and then inter-phase calculations, this invention achieves a complete assessment of the opening and closing synchronism of three-phase multi-vacuum-break switchgear under all operating conditions, providing a comprehensive and accurate decision-making basis for equipment condition-based maintenance and fault diagnosis.

[0075] The following is a specific embodiment to further illustrate the above-mentioned method and system for measuring the opening and closing synchronicity of multi-vacuum-break switchgear: First, such as Figure 2 As shown, the synchronicity measurement system for opening and closing of multi-vacuum circuit breaker consists of a power supply module, a vacuum interrupter, a control module, a data acquisition and measurement module, and a main control unit. Specifically, the power supply module comprises an LC equivalent current source, a main circuit switch, thyristors, and anti-parallel diodes; the control module consists of a main control unit operation control platform; and the data acquisition and measurement module consists of a high-voltage probe and a digital acquisition card. The main control unit sends control signals to charge the LC current source capacitor and close the main switch; the STM32 microcontroller sends trigger signals to the thyristors, the digital acquisition card, and the operating mechanism of the vacuum circuit breaker; the high-voltage side of the voltage probe is connected to the stationary contact side of the vacuum interrupter, and the low-voltage side is connected to the moving contact side of the vacuum interrupter, transmitting the measured arc voltage signal to the digital acquisition card. The main control unit is connected to the output of the digital acquisition card to store the time-arc voltage data transmitted by the digital acquisition card. By analyzing the time-arc voltage data, the time point of arc voltage abrupt change is found, the inherent opening time of the vacuum circuit breaker is determined, and ten sets of experiments are repeated. Considering the inherent dispersion of the opening time of vacuum switchgear, the accurate inherent opening time of each vacuum switchgear is obtained by averaging the ten sets of data.

[0076] Furthermore, a power supply module adapted to the above system is disclosed, achieving miniaturization, lightweight design, modularity, and integration while ensuring normal power supply. The power supply can be an LC equivalent current source or a DC voltage source. This embodiment selects an LC equivalent current source as the power supply module. The LC equivalent current source has a power supply frequency of 50Hz, an inductance L=33mH, and a voltage coefficient C=307. The charging and discharging circuit includes a pre-charging circuit consisting of a DC charging power supply, a charging switch, and a capacitor, and a discharging circuit consisting of a capacitor, a discharge resistor, and a vacuum contactor. The DC charging power supply pre-charges the capacitor by closing the charging switch; the charging voltage of the DC charging power supply is 150V, and the charging current is 1500mA. At the end of the test, the vacuum contactor closes, and the remaining energy in the capacitor is consumed through the discharge resistor. The main switch controls the power supply to the main circuit; when the main switch is on, the power supply current to the main circuit does not exceed 500A. After the test, the circuit is completely disconnected to ensure operational safety and equipment isolation. The thyristor mainly plays a role in precise signal timing control and current conduction, ensuring that current is injected into the vacuum interrupter at specific times; the reverse parallel diode suppresses reverse voltage, protecting the thyristor.

[0077] Accordingly, such as Figure 3 As shown, the multi-vacuum circuit breaker under test includes arc-extinguishing chambers V1 and V2. High-voltage probes are connected across both ends of the dual-vacuum circuit breaker to measure the arc voltage signal. High-frequency response vibration sensors A1 and A2 are installed on the rigid housing of the stationary contact side of each vacuum arc-extinguishing chamber to measure vibration and impact signals. The outputs of the high-voltage probes and vibration sensors are connected to a digital acquisition card, and the data is exported to the main control unit for subsequent data processing.

[0078] Specifically, a single-phase tripping synchronization test is performed. The STM32 microcontroller is pre-set with timing parameters: t1 is the interval between the trigger signals of V1 and V2, t2 is the interval from V2 triggering to S1 conduction, and t3 is the expected contact start time. The timing control logic is as follows: The main control unit sends a control signal to the main controller to pre-charge the LC current source capacitor and close the main switch; at time t0, the STM32 microcontroller sends trigger signals to the operating mechanism of vacuum interrupter V1 and the digital acquisition card; after a delay of t1, it sends a trigger signal to the operating mechanism of vacuum interrupter V2; after another delay of t2, it sends a trigger signal to the thyristor, causing the main circuit current to conduct. The double-break vacuum interrupter begins the tripping operation; theoretically, at the set time t3, the moving contacts of the two vacuum interrupters should begin to separate simultaneously. However, due to mechanical dispersion, the actual separation time will differ. The vacuum interrupter that opens first forms a vacuum arc first, followed by the other vacuum interrupter that opens later. The digital acquisition card can simultaneously acquire data collected by all high-voltage probes and vibration sensors throughout the entire circuit breaker tripping process.

[0079] Furthermore, a single-phase closing synchronization test was performed. After the dual-vacuum-break switchgear stably opened, the power module was restored to its state before opening. The STM32 microcontroller was pre-set with timing parameters: t1 was the interval between the trigger signals of S1 and V1, V2, and t2 was the expected moment when the contacts would begin to move. The timing control logic was as follows: the main control unit sent a control signal to the main controller to pre-charge the LC current source capacitor and close the main switch; at time t0, the STM32 microcontroller sent a trigger signal to the thyristor; after a delay of t1, a closing trigger signal was sent to both vacuum interrupters simultaneously; at the set time t3, theoretically, the moving contacts of the two vacuum interrupters would begin to close simultaneously. However, due to mechanical dispersion, the actual closing time would differ. Since the arc voltage signal characteristics changed less significantly during closing than during opening, vibration sensors were mainly used to accurately identify the closing time of each break. The vacuum interrupter that closed first generated a strong vibration signal, followed by the other vacuum interrupter that closed later. The digital acquisition card synchronously acquires data collected by all vibration sensors throughout the entire closing process.

[0080] Accordingly, such as Figure 4 As shown, compared to a single-phase system, the single-phase dual-vacuum-break switch circuit is expanded into a three-phase dual-vacuum-break switch branch (A, B, C). The three-phase multi-vacuum-break switchgear is equipped with a data acquisition and measurement device. During each test, the multi-vacuum-break switch of the phase being tested is replaced, and the data acquisition and measurement device is connected to the switch of the phase being tested. This allows for the testing of the opening and closing of each phase of the multi-vacuum-break switchgear, obtaining the synchronicity data of the opening and closing of each vacuum break in the same phase and the synchronicity data of the opening and closing of the multi-vacuum breaks across the three phases.

[0081] First, a three-phase tripping synchronism test is performed. The process is similar to the single-phase tripping test described above. Under identical conditions, the vacuum switches corresponding to the A, B, and C phase branches are connected sequentially for testing, measuring the tripping synchronism of the dual-vacuum-break switchgear in each branch. The arc voltage signal detected by the high-voltage probe and the vibration signal detected by the vibration sensor are used to identify the tripping start time of each break, obtaining the synchronism test data for each phase, and then analyzing the tripping synchronism among phases A, B, and C. Next, a three-phase closing synchronism test is performed. The process is similar to the single-phase closing test described above. Under identical conditions, the control switches corresponding to the A, B, and C phase branches are connected sequentially for testing, measuring the closing synchronism of the dual-vacuum-break switchgear in each branch. The vibration signal detected by the vibration sensor is used to identify the contact closing time of each break, obtaining the synchronism test data for each phase, and then analyzing the closing synchronism among phases A, B, and C. Furthermore, the experiment was repeated 5 times, and the synchronicity data of the opening and closing of the three-phase process were obtained for each of the 5 times. After data processing, the average value of the synchronicity measurement of the 5 processes was calculated.

[0082] In synchronous measurements, due to the dispersion of mechanical and measurement aspects, problems exist such as difficulty in accurately determining the starting point of the arc voltage signal and significant disturbances in the vibration signal from the vibration sensor. To minimize data processing errors and improve the accuracy of time point interpretation, this invention discloses a comprehensive data feature extraction method integrating arc voltage and vibration signals to accurately identify the starting point of opening and closing. Through signal data preprocessing, data feature extraction, and the combined effect of multi-source information, the starting time of opening and closing is obtained, thereby determining the synchronous problem. This compensates for the shortcomings of a single signal, significantly reduces errors caused by dispersion, and makes the starting time of opening and closing at each break point closer to the actual situation, fundamentally improving the reliability and accuracy of synchronous calculations.

[0083] The detailed implementation process of each step of the above method is as follows: First, data preprocessing is performed on each signal: the arc voltage signal's main energy is concentrated at lower frequencies, therefore a cutoff frequency is set, and a 5th-order Butterworth low-pass filter is used to filter out high-frequency noise. Simultaneously, the mean value of the signal preceding the arc voltage is calculated and subtracted from the entire signal to eliminate DC bias interference and ensure the arc voltage rises from zero reference. Bandpass filtering is used on the vibration signal, with the passband covering the characteristic frequencies of the operating mechanism and the arc-extinguishing chamber's mechanical impacts. This preserves the vibration components generated by critical mechanical impacts during opening and closing, while suppressing low-frequency environmental vibrations and high-frequency electrical noise.

[0084] Secondly, feature points of the preprocessed arc voltage signal and vibration signal are identified separately. The specific process is as follows: The first derivative of the preprocessed arc voltage signal is calculated using the finite difference method. A low slope threshold is set. When the slope of several consecutive points exceeds this threshold, the region is marked as the "rising start zone" to avoid disturbance errors caused by the small slope at the starting point. Then, within this time window, the inflection point where the change of the first derivative of the arc voltage signal exceeds the threshold is found. The corresponding time is... The preprocessed vibration signal is subjected to Hilbert transform to extract its envelope, converting the high-frequency oscillation signal into a smooth curve reflecting energy impact changes, thus highlighting the energy pulse caused by mechanical impact. On the envelope, all peaks significantly larger than the background noise are identified, and the point where the rising edge of each peak reaches 20% of its peak value is found, corresponding to a time interval of [missing information]. .

[0085] Next, the arc voltage signal and vibration signal information are fused and cross-verified to obtain the final opening and closing times of each fault. The specific process is as follows: When processing the tripping signal, the characteristic change points of each arc voltage step signal are identified, and the time difference between the tripping of each vacuum switch is calculated. The time corresponding to the point where the amplitude of each vibration signal reaches 20% of its peak value on the rising edge is measured and taken as the tripping start time of that vacuum switch, thus determining the tripping sequence of each vacuum switch. When processing the closing signal, the order and time difference of the closing of each vacuum switch are determined by the order and intensity of the vibration signal amplitudes.

[0086] Next, the acquisition and measurement module was sequentially connected to the double-break vacuum switches corresponding to the three-phase branches A, B, and C to obtain the test data for the synchronicity of the three-phase opening and closing. By comparing the opening and closing data between the three phases, the time difference between the opening and closing of the corresponding vacuum switches between phases was calculated.

[0087] Taking phases A and B as examples, the starting times of the opening of each vacuum interrupter chamber are obtained by jointly measuring the arc voltage signal (calculated by the time difference) and the vibration signal (used to determine the order of opening). The corresponding time difference for the start of the circuit breaker tripping is: The time difference between the start of the tripping of the overall vacuum interrupter chambers of phases A and B is: By analogy, the starting time difference of the tripping of the three-phase double-vacuum circuit breaker can be obtained.

[0088] Furthermore, taking phases A and B as examples, the closing start times of each vacuum switch were measured based on the order and intensity of the vibration signal amplitudes. The corresponding closing time difference of each vacuum switch is The closing time difference between the overall vacuum interrupters of phases A and B is: By analogy, the starting time difference for closing the three-phase double-vacuum circuit breaker can be obtained.

[0089] Finally, the opening and closing time difference of single-phase multi-series vacuum switches and the opening and closing time difference of corresponding dual vacuum break switches between phases are compared with the set thresholds to determine the synchronicity of opening and closing of multi-vacuum break switchgear.

[0090] Based on the foregoing, the synchronization problem of opening and closing of the single-phase / three-phase dual-vacuum circuit breaker was repeated 5 times, and 5 sets of data were obtained for each synchronization problem. The average value was taken as the final opening and closing start time, which was used to verify and judge the synchronization of opening and closing of the single-phase / three-phase dual-vacuum circuit breaker.

[0091] The software compares the final synchronization data obtained by S5 with the set threshold: if it is greater than the set threshold, a "warning" result is output; if it is less than the set threshold, a "normal" result is output. The software integrates all test data and generates a comprehensive report for the user. The report includes: the inherent opening time of each vacuum break switchgear, the original waveform diagram of each test, the processed feature point marking diagram, the statistical results of the synchronization data of single-phase / three-phase opening and closing tests, and the diagnostic conclusions compared with the preset threshold.

[0092] Accordingly, a second aspect of the present invention provides an electronic device, including: at least one processor; and a memory connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to cause the at least one processor to perform the above-described method for measuring the opening and closing synchronism of a multi-vacuum-break switchgear.

[0093] Accordingly, a third aspect of the present invention provides a computer-readable storage medium having computer instructions stored thereon, which, when executed by a processor, implement the above-described method for measuring the synchronicity of opening and closing of a multi-vacuum-break switchgear.

[0094] The embodiments of the present invention aim to protect a method for measuring the opening and closing synchronicity of multi-vacuum-break switchgear, which has the following effects: 1. By using a non-invasive sensor configuration where a high-voltage probe is connected across both ends of the multi-vacuum break switchgear under test and vibration sensors are installed on the side of the stationary contact cover of each vacuum interrupter, effective acquisition of internal action information of multiple breaks is achieved without damaging the equipment's sealing structure or affecting internal insulation. This solves the technical problem that the electrical parameters of each break cannot be directly measured because the vacuum interrupter is sealed inside a metal shell, and provides a feasible technical approach for measuring the opening and closing synchronicity of multi-vacuum break switchgear. 2. By synchronously acquiring arc voltage signals and vibration signals during the opening and closing operations, and fusing them based on the complementary characteristics of the two signals, the advantages of the arc voltage signal having obvious step characteristics during the opening process and the vibration signal having prominent impact characteristics during the closing process are fully utilized. This overcomes the shortcomings of single signal detection methods, such as difficulty in taking into account both the opening and closing processes, susceptibility to environmental interference, and limited accuracy, and significantly improves the accuracy and reliability of synchronous measurement. 3. By performing rate-of-change analysis and inflection point identification on arc voltage signals, and extracting the envelope of vibration signals and locating the rising edge at a preset ratio, a high-precision feature recognition method is developed. This effectively eliminates the influence of signal disturbance, background noise, and mechanical dispersion on feature point interpretation, and achieves precise positioning of the moment when each vacuum break is just opened and closed. This provides a reliable data foundation for accurately judging the synchronicity of opening and closing of multi-vacuum break switchgear, thereby ensuring the breaking capacity and operational safety of the equipment.

[0095] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0096] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0097] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0098] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0099] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for measuring the synchronicity of opening and closing of a multi-vacuum-break switchgear, characterized in that, The measurement method is based on a multi-vacuum break switchgear opening and closing synchronism measurement system. This system includes at least a power supply module, a control module, a data acquisition and measurement module, and a post-processing module. The data acquisition and measurement module includes a high-voltage probe and several vibration sensors. The high-voltage probe is connected across the two ends of the multi-vacuum break switchgear under test. The vibration sensors are respectively installed on the side of the stationary contact cover of each vacuum interrupter chamber. The measurement method includes the following steps: The control module controls the power module to supply power to the multi-vacuum circuit breaker under test, and controls the multi-vacuum circuit breaker under test to perform opening and / or closing operations. The acquisition and measurement module synchronously acquires the arc voltage signal and vibration signal generated during the opening and / or closing operation to obtain the raw signal data. The post-processing module processes the original signal data to extract the moment of opening and / or closing of each vacuum break, and obtains the measurement results of the synchronicity of opening and closing of the multi-vacuum break switchgear based on the moment of opening and / or closing.

2. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 1, characterized in that, The post-processing module processes the raw signal data to extract the instantaneous opening and / or instantaneous closing moments of each vacuum break, and obtains the measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear based on the instantaneous opening and / or instantaneous closing moments, including: The arc voltage signal and vibration signal in the original signal data are respectively identified to obtain the arc voltage step feature point and the corresponding candidate opening time of each vacuum break during the opening process, and to obtain the vibration impact feature point and the corresponding candidate vibration time of each vacuum break during the opening and / or closing process. Based on the candidate opening time and the candidate vibration time of each vacuum break, the moment when each vacuum break is opened is obtained, and based on the candidate vibration time of each vacuum break, the moment when each vacuum break is closed is obtained. The opening time difference between different vacuum breaks is calculated based on the moment when each vacuum break just opens, and the closing time difference between different vacuum breaks is calculated based on the moment when each vacuum break just closes, thus obtaining the measurement results of the synchronicity of opening and closing of multi-vacuum-break switchgear.

3. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 2, characterized in that, Feature identification of the arc voltage signal in the original signal data includes: The arc voltage signal in the original signal data is subjected to low-pass filtering and DC bias elimination processing to obtain the preprocessed arc voltage signal. Calculate the rate of change of the preprocessed arc voltage signal, and mark the signal interval in which the rate of change continuously exceeds a preset slope threshold as the arc voltage step start region; Within the arc voltage step start region, the position where the change in the rate of change exceeds a preset inflection point threshold is identified, and the corresponding time point is taken as the occurrence time of the arc voltage step feature point, and the occurrence time of the arc voltage step feature point is taken as the candidate opening time.

4. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 2, characterized in that, Feature identification of vibration signals in the original signal data includes: The vibration signal in the original signal data is subjected to bandpass filtering to obtain the preprocessed vibration signal; Envelope extraction is performed on the preprocessed vibration signal to obtain an envelope curve reflecting the change of vibration energy over time; On the envelope curve, identify impact peaks whose amplitude exceeds a preset background noise threshold. The time corresponding to the position where the amplitude of the impact peak first reaches a preset proportion of the impact peak amplitude during the rising edge is taken as the vibration impact feature point, and the time corresponding to the vibration impact feature point is taken as the candidate vibration moment.

5. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 4, characterized in that, The step of identifying impact peaks on the envelope curve whose amplitude exceeds a preset background noise threshold, and taking the time corresponding to the position where the amplitude of the impact peak first reaches a preset proportion of the impact peak amplitude during the rising edge of the impact peak as the vibration impact feature point, includes: After identifying the impact peak value with an amplitude exceeding a preset background noise threshold on the envelope curve, the rising edge interval of the impact peak value is determined. Within the rising edge interval, the trajectory of the amplitude change from the rising starting point to the peak impact is calculated, and the time corresponding to the position where the amplitude first reaches a preset proportion of the peak impact amplitude is taken as the vibration impact feature point.

6. The method for measuring the synchronicity of opening and closing of a multi-vacuum-break switchgear according to any one of claims 1-5, characterized in that, The control of the multi-vacuum-break switchgear under test to perform opening and / or closing operations includes: When the circuit breaker trips, the control module sends a trigger signal according to a preset timing parameter, including: sending a trigger signal to the operating mechanism of the first vacuum break and the acquisition and measurement module at a first moment; sending a trigger signal to the operating mechanism of the second vacuum break after a first preset delay; and sending a trigger signal to the thyristor in the power supply module after a second preset delay to turn on the test circuit current. When the closing operation is performed, the control module sends a trigger signal according to the preset timing parameters, including: sending a trigger signal to the thyristor in the power module at a second moment; and after a third preset delay, simultaneously sending a closing trigger signal to the operating mechanism of all vacuum breaks.

7. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 6, characterized in that, Before controlling the multi-vacuum-break switchgear under test to perform opening and / or closing operations, the method further includes: The inherent opening time of each vacuum break is measured separately to obtain the inherent opening time of each vacuum break. The timing parameters of the control module are set according to the inherent opening time of each vacuum break, so that the timing at which the control module sends a trigger signal to the operating mechanism of each vacuum break matches the inherent opening time of that vacuum break.

8. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 1, characterized in that, The multi-vacuum break switch device under test is a three-phase multi-vacuum break switch device, and the three-phase multi-vacuum break switch devices share one of the acquisition and measurement modules. The method of synchronously acquiring arc voltage signals and vibration signals generated during the opening and / or closing operations through the acquisition and measurement module includes: The acquisition and measurement module is sequentially connected to the multi-vacuum circuit breaker of the current phase to be tested, and the opening and / or closing tests are performed on each phase to obtain the opening and closing synchronicity data of each phase. The measurement results of the opening and closing synchronicity of the multi-vacuum break switchgear obtained based on the instantaneous opening and / or instantaneous closing times include: The opening and / or closing time differences of the corresponding vacuum breaks between different phases are calculated based on the opening and / or closing times of each phase to obtain the measurement results of the opening and closing synchronicity of the three-phase multi-vacuum-break switchgear.

9. The method for measuring the synchronicity of opening and closing of multi-vacuum-break switchgear according to claim 1, characterized in that, The control module includes a main control unit operation control platform and a main controller; The main controller generates trigger signals based on the control commands sent by the main control unit operation control platform to control the switching of the power module, the operation of the operating mechanism of the multi-vacuum-break switchgear under test, and the signal acquisition timing of the acquisition and measurement module.

10. The method for measuring the synchronicity of opening and closing of a multi-vacuum-break switchgear according to claim 1, characterized in that, The vibration sensor is mounted on the rigid housing on the side of the stationary contact cover plate.

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