Overvoltage suppression method for opening operation of circuit breaker

Abstract

The invention discloses an overvoltage suppression method for opening operation of a circuit breaker, and the method comprises the steps: monitoring the transient voltage change of each key node of a system in an opening operation process; a distributed multi-point suppression mode is selected according to the node voltage state, and the opening angle of the circuit breaker is adjusted according to the voltage and current state detected in real time; under the condition that transient overvoltage occurs, line impedance is instantaneously adjusted to delay voltage rise, and a small capacitor is added in an opening loop to perform instantaneous voltage absorption; based on the fault feature analysis of the line, an impending overvoltage is warned and an adaptive adjustment operation is triggered. According to the method, the reliability of overvoltage suppression is improved, the fault risk of power equipment is reduced, the overall stability and operation safety of a power system are further enhanced, and the method has high application and popularization value.

Description

Technical Field

[0001] The present invention relates to the technical field of overvoltage suppression, and in particular to an overvoltage suppression method for circuit breaker opening operation. Background Art

[0002] With the continuous expansion of the scale and complexity of the power system, the overvoltage problem generated by the circuit breaker during the opening operation has gradually attracted attention. Traditional overvoltage suppression methods usually rely on fixed RC absorbers, lightning arresters and other equipment, but these devices are difficult to achieve dynamic adjustment in complex opening scenarios, especially in multi-node distributed power grids. The propagation path and fluctuation characteristics of overvoltage are not easy to control, which can easily cause system oscillation or equipment damage. In addition, the reignition of the arc during the opening process will further increase the amplitude of the transient overvoltage, posing a threat to the stability of the power grid and the safe operation of the equipment. Therefore, there is an urgent need for an overvoltage suppression method based on real-time monitoring and intelligent control, so as to automatically identify overvoltage precursors under different opening conditions and take targeted suppression measures in time to achieve precise control of transient overvoltage. Summary of the invention

[0003] In view of the above existing problems, the present invention is proposed.

[0004] Therefore, the present invention provides an overvoltage suppression method for circuit breaker opening operation, aiming to solve the problems of inflexible overvoltage suppression during circuit breaker opening operation, difficult coordinated response of distributed nodes, and high-frequency oscillation caused by arc reignition. The present invention introduces a multi-point distributed suppression module, a real-time monitoring system, and an intelligent control mechanism, and can dynamically adjust the opening angle and line impedance according to the characteristic information of transient voltage and current during the opening process, so as to effectively manage the propagation path, fluctuation frequency, and amplitude of the overvoltage. At the same time, the present invention also identifies the precursors of overvoltage events through fault feature analysis and early warning mechanisms, and actively triggers suppression operations to cope with complex opening scenarios and achieve synchronous coordination of multi-node suppression. These technical means enable the system to flexibly respond to overvoltage problems under different working conditions, thereby meeting the high reliability and safety requirements of the power system.

[0005] In order to solve the above technical problems, the present invention provides the following technical solution, an overvoltage suppression method for circuit breaker opening operation, comprising:

[0006] During the opening operation, monitor the transient voltage changes at each key node of the system;

[0007] Select a distributed multi-point suppression method based on the node voltage status, and adjust the circuit breaker opening angle based on the voltage and current status detected in real time;

[0008] In the event of transient overvoltage, the line impedance is instantaneously adjusted to delay the voltage rise, and a small capacitor is added to the trip circuit to absorb the transient voltage;

[0009] Based on the fault feature analysis of the line, it warns of impending overvoltage and triggers adaptive adjustment operations.

[0010] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation described in the present invention, the key nodes include bus nodes, branch nodes, transformer interface nodes, load end nodes, and circuit breaker contact nodes.

[0011] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation described in the present invention, wherein: the transient voltage changes of each key node of the monitoring system include obtaining the transient voltage changes at each key node position by distributed monitoring of the voltage amplitude and phase of each key node. The distributed monitoring system uses high-precision sensors to collect voltage and phase data at each key node and transmits it to the central control system to form a multi-node transient voltage database;

[0012] The central control system determines the voltage fluctuation characteristics of each node based on real-time transient data analysis to determine the key node locations where overvoltage may occur during the opening operation. When the opening operation is performed, the corresponding suppression position is selected according to the monitored transient voltage data and the multi-point suppression operation is triggered synchronously, so that the suppression module of each node responds to the operation instruction within the selected time node.

[0013] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation described in the present invention, wherein: the multi-point suppression method includes, during the multi-point suppression process, the central control system sets the response timing of each node according to the voltage fluctuation and phase difference of each key node;

[0014] The central control system analyzes the transient voltage change trend during the opening operation and assigns different response delays to each node to form a distributed response sequence. Each node receives the suppression instruction according to the preset response sequence and performs voltage adjustment and load adjustment in turn, thereby controlling the propagation of overvoltage waves during the opening process.

[0015] By gradually activating adjacent nodes to perform multi-point coordinated suppression operations, the energy of the voltage wave is transmitted layer by layer along the suppression nodes, achieving a phased dispersion of the overvoltage energy. At the same time, the coordinated response between the nodes is kept consistent through timing control. During the opening operation, the overvoltage energy at different locations is gradually decomposed and transferred to the next-level node until the global multi-point response chain is completed.

[0016] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation described in the present invention, the real-time detection includes high-frequency sampling of the current polarity, residual voltage amplitude and polarity difference of the line voltage in the line, capturing the instantaneous direction change of the current in the line through the current sensor, analyzing the polarity and identifying the moment when the current approaches the zero crossing point, and at the same time, the detection system records the instantaneous amplitude of the residual voltage to obtain the distribution of the residual energy on the line;

[0017] The voltage polarity is detected by collecting waveform data in real time through the voltage sensor, comparing the voltage polarity difference before and after the opening of the switch, and determining the phase relationship between the current and voltage. At the moment when the contact opening distance reaches the maximum value, the central controller selects a specific opening angle and adjusts the triggering timing of the opening according to the polarity difference of the current and voltage.

[0018] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation described in the present invention, wherein: the instantaneous voltage absorption includes connecting a small capacitor to the opening circuit, and controlling the charging and discharging rate of the capacitor during the current fluctuation period by dynamically adjusting the charging and discharging time constant, wherein the adjustment of the time constant is based on the instantaneous characteristics of the current and voltage waveforms, so that the capacitor gradually reaches a preset charging state before the current peak occurs, and releases the stored charge during the current drop period;

[0019] After the switch is opened, the capacitor in the circuit gradually absorbs and releases charges, changing the transient response characteristics of the circuit. The oscillation frequency gradually changes from the original high frequency to a low frequency to adapt to the impedance change of the circuit and control the amplitude of the current fluctuation.

[0020] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation of the present invention, wherein: the fault characteristic analysis of the line includes combining historical data analysis with real-time collected information to comprehensively analyze the fault characteristics in the line;

[0021] A fault feature library is built based on historical operating data, which includes voltage and current change trends and fluctuation frequency parameters under different working conditions. During real-time monitoring, the waveform characteristics of the current voltage and current are continuously compared with the data in the fault feature library, the similarity is analyzed and abnormal changes are detected. By calculating the instantaneous deviation and fluctuation rate of the current waveform, potential overvoltage precursor characteristics are identified. After identifying the precursor characteristics, the system generates a warning signal to indicate that a possible overvoltage state is about to occur and starts the preparation process for the tripping suppression step.

[0022] As a preferred solution of the overvoltage suppression method for circuit breaker opening operation described in the present invention, wherein: the triggering adaptive adjustment operation includes: if the voltage rises rapidly and the amplitude significantly exceeds the rated voltage level in the current cycle, while the current fluctuates slightly or remains below the preset level, the fluctuation frequency is higher than the preset standard and frequent sudden increases occur, then the system identifies it as a precursor to a high voltage event; when this happens, the system will issue a first-level early warning signal, start the multi-point distributed suppression mode in advance, and gradually activate the distributed suppression modules of different nodes, and adjust the opening angle before the contacts are disconnected to delay arc generation; if the voltage fluctuates briefly at a low frequency and significantly at certain moments, that is, the fluctuation amplitude exceeds the preset range, and the current fluctuates slowly and periodically, it indicates that the system is in an overloaded state, the fluctuation frequency is low but the amplitude is large, The system identifies it as a precursor to a low-frequency transient disturbance; when this happens, the system issues a second-level warning signal, adjusts the charging and discharging time constant of the capacitor absorption to adapt to low-frequency fluctuations, and slows down the rate at which the contact opening distance increases; if the voltage and current oscillate rapidly and at a high frequency, and the fluctuation frequency is significantly higher than the steady-state frequency, usually above several thousand hertz, the system identifies it as a precursor to a high-frequency oscillation; when this happens, the system issues a third-level warning signal, triggering a low-capacitance absorption operation, dynamically adjusting the current peak delay through a small capacitor and increasing the impedance to reduce the oscillation frequency; if the current increases significantly during the current cycle and the voltage is relatively stable, and the current amplitude rises rapidly, the system identifies it as a precursor to a current shock event; when this happens, the system issues a fourth-level warning signal, adds a high-impedance access step before opening the switch, and instantly adjusts the contact disconnection angle. If the voltage and current fluctuate repeatedly in the current cycle, with a high frequency and the number of changes exceeding the preset standard, the system will identify it as a precursor to multiple transient disturbances; when this happens, the system will issue a five-level warning signal, gradually guiding the overvoltage energy to disperse in the low-frequency direction, and controlling the change in the opening distance of the contacts to maintain a relatively stable increase rate.

[0023] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and wherein the processor implements the steps of an overvoltage suppression method for a circuit breaker opening operation when executing the computer program.

[0024] A computer-readable storage medium having a computer program stored thereon, characterized in that when the computer program is executed by a processor, the steps of an overvoltage suppression method for a circuit breaker opening operation are implemented.

[0025] Beneficial effects of the present invention: The present invention realizes precise control of transient overvoltage during the circuit breaker opening operation through multi-point distributed real-time monitoring and intelligent suppression technology, providing higher flexibility and response speed. The early warning mechanism based on intelligent fault feature analysis can identify potential overvoltage events in advance, reasonably arrange suppression operations, and enable the system to achieve effective management of overvoltage energy under dynamic distribution conditions. At the same time, through the adaptive adjustment of the opening angle and impedance, the probability of arc reignition and high-frequency oscillation is effectively controlled. The implementation of the present invention not only improves the reliability of overvoltage suppression and reduces the failure risk of power equipment, but also further enhances the overall stability and operational safety of the power system, and has great application and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0027] Figure 1 A schematic flow chart of an overvoltage suppression method for circuit breaker opening operation provided in accordance with an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0029] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0030] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0031] The present invention is described in detail with reference to schematic diagrams. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0032] At the same time, in the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper, lower, inner and outer" are based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0033] In the present invention, unless otherwise clearly specified and limited, the terms "install, connect, connect" should be understood in a broad sense, for example: it can be a fixed connection, a detachable connection or an integral connection; it can also be a mechanical connection, an electrical connection or a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] Example 1, reference Figure 1 , which is the first embodiment of the present invention, provides an overvoltage suppression method for circuit breaker opening operation, comprising:

[0035] S1: During the opening operation, monitor the transient voltage changes of key nodes in the system.

[0036] S2: Select the distributed multi-point suppression method according to the node voltage status, and adjust the circuit breaker opening angle according to the real-time detected voltage and current status.

[0037] S3: In the event of transient overvoltage, the line impedance is instantaneously adjusted to slow down the voltage rise, and a small capacitor is added to the trip circuit to absorb the transient voltage.

[0038] S4: Based on the fault feature analysis of the line, it warns of impending overvoltage and triggers adaptive adjustment operations.

[0039] The key nodes include bus nodes, branch nodes, transformer interface nodes, load end nodes, and circuit breaker contact nodes.

[0040] The monitoring system includes monitoring the transient voltage changes of each key node of the system by distributed monitoring of the voltage amplitude and phase of each key node to obtain the transient voltage changes of each key node. The distributed monitoring system uses high-precision sensors to collect voltage and phase data at each key node and transmits it to the central control system to form a multi-node transient voltage database;

[0041] The central control system determines the voltage fluctuation characteristics of each node based on real-time transient data analysis to determine the key node locations where overvoltage may occur during the opening operation. When the opening operation is performed, the corresponding suppression position is selected according to the monitored transient voltage data and the multi-point suppression operation is triggered synchronously, so that the suppression module of each node responds to the operation instruction within the selected time node.

[0042] The multi-point suppression method includes, during the multi-point suppression process, the central control system sets the response timing of each node according to the voltage fluctuation and phase difference of each key node;

[0043] The central control system analyzes the transient voltage change trend during the opening operation and assigns different response delays to each node to form a distributed response sequence. Each node receives the suppression instruction according to the preset response sequence and performs voltage adjustment and load adjustment in turn, thereby controlling the propagation of overvoltage waves during the opening process.

[0044] By gradually activating adjacent nodes to perform multi-point coordinated suppression operations, the energy of the voltage wave is transmitted layer by layer along the suppression nodes, achieving a phased dispersion of the overvoltage energy. At the same time, the coordinated response between the nodes is kept consistent through timing control. During the opening operation, the overvoltage energy at different locations is gradually decomposed and transferred to the next-level node until the global multi-point response chain is completed.

[0045] The real-time detection includes high-frequency sampling of the current polarity, residual voltage amplitude and polarity difference of the line voltage in the line, capturing the instantaneous direction change of the current in the line through the current sensor, analyzing the polarity and identifying the moment when the current is close to the zero crossing point, and at the same time, the detection system records the instantaneous amplitude of the residual voltage to obtain the distribution of the residual energy on the line;

[0046] The voltage polarity is detected by collecting waveform data in real time through the voltage sensor, comparing the voltage polarity difference before and after the opening of the switch, and determining the phase relationship between the current and voltage. At the moment when the contact opening distance reaches the maximum value, the central controller selects a specific opening angle and adjusts the triggering timing of the opening according to the polarity difference of the current and voltage.

[0047] Assume that the voltage of the system at any time t is V(t) = V m sin(ωt+θ v ), the current is I(t)=I msin(ωt+θ i ), where V m and I m are the maximum amplitudes of voltage and current respectively; ω is the angular frequency, defined as ω=2πf; θ v and θ i are the initial phases of voltage and current respectively.

[0048] By real-time monitoring of the zero-crossing point of the system current, that is, I(t) = 0, the optimal phase angle when the opening contact is disconnected can be obtained. The specific calculation method is:

[0049] Determine the current zero point: Assume that the current reaches zero at t = t0, then

[0050]

[0051] Calculate the instantaneous value of the voltage when the switch is open: At t = t0, the voltage is

[0052] V(t0)=V m sin(ωt0+θ v

[0053] Optimize contact separation angle: In order to achieve the best suppression effect at the moment of opening, the contact opening distance d is introduced. Assuming that the opening distance reaches the maximum value within the time Δt after disconnection, the opening distance increment is defined as

[0054] d(t)=d max (1-e -αt ),

[0055] Where α is an adjustment parameter, which is calibrated through experimental data to ensure that the opening distance increases as quickly as possible during the opening period.

[0056] In order to further optimize the opening angle and minimize the overvoltage amplitude, a creative phase difference model is introduced:

[0057] Δθ=|θ v -θ i

[0058] When Δθ is close to a multiple of π / 2, the phase difference between current and voltage is minimal, and the impact of the opening operation on overvoltage is also minimal. Therefore, the optimal opening angle should satisfy:

[0059]

[0060] In practical applications, Δθ is calculated based on the voltage and current data collected in real time, and the opening operation is performed when Δθ≈π / 2 is satisfied to achieve the best suppression effect.

[0061] Where V(t) represents the voltage value at any time t (volts, V); Vm It represents the maximum amplitude of the voltage, that is, the peak value of the voltage waveform (volts, V); ω represents the electrical angular frequency, in radians per second, and is defined as ω = 2πf, where f is the frequency of the power supply (usually 50Hz or 60Hz); θ v represents the initial phase angle of the voltage, which represents the initial phase of the voltage waveform (radians); I(t) represents the current value (ampere, A) at any time t; I m Indicates the maximum amplitude of the current, that is, the peak value of the current waveform (ampere, A); θ i represents the initial phase angle of the current, which represents the initial phase of the current waveform (radians); t0 represents the moment when the current reaches zero, which represents the time when the current crosses the zero point (seconds, s); n represents an integer, which is used to represent the number of times the current crosses the zero point (dimensionless); d(t) represents the contact opening distance at any time t, that is, the distance between the opening contacts (meters, m); d max Indicates the maximum value of the contact opening distance, the maximum opening distance that the contact finally reaches after the opening operation (meter, m); α indicates the adjustment parameter for the increase of the contact opening distance, which controls the rate of increase of the opening distance (inverse of seconds, s -1 ), Δθ represents the phase difference between voltage and current, defined as Δθ=|θ v -θ i |(radians);θ opt represents the optimal opening angle, that is, the phase angle (radians) under the condition of minimum overvoltage in the opening operation; k represents an integer, which is used to adjust the multiple of the phase difference so that the opening operation occurs when the phase difference is close to a multiple of π / 2 (dimensionless).

[0062] The instantaneous voltage absorption includes connecting a small capacitor to the switch-off circuit and controlling the charge and discharge rate of the capacitor during the current fluctuation by dynamically adjusting the charge and discharge time constant, wherein the adjustment of the time constant is based on the instantaneous characteristics of the current and voltage waveforms, so that the capacitor gradually reaches a preset charge state before the current peak occurs, and releases the stored charge during the current drop;

[0063] After the switch is opened, the capacitor in the circuit gradually absorbs and releases charges, changing the transient response characteristics of the circuit. The oscillation frequency gradually changes from the original high frequency to a low frequency to adapt to the impedance change of the circuit and control the amplitude of the current fluctuation.

[0064] The fault characteristic analysis of the line includes combining historical data analysis with real-time collected information to comprehensively analyze the fault characteristics in the line;

[0065] A fault feature library is built based on historical operating data, which includes voltage and current change trends and fluctuation frequency parameters under different working conditions. During real-time monitoring, the waveform characteristics of the current voltage and current are continuously compared with the data in the fault feature library, the similarity is analyzed and abnormal changes are detected. By calculating the instantaneous deviation and fluctuation rate of the current waveform, potential overvoltage precursor characteristics are identified. After identifying the precursor characteristics, the system generates a warning signal to indicate that a possible overvoltage state is about to occur and starts the preparation process for the tripping suppression step.

[0066] The triggering of the adaptive adjustment operation includes: if the voltage rises rapidly and the amplitude significantly exceeds the rated voltage level in the current cycle, while the current fluctuates slightly or remains below the preset level, and the fluctuation frequency is higher than the preset standard and frequent sudden increases occur, the system recognizes it as a precursor to a high voltage event; when this happens, the system will issue a first-level early warning signal, start the multi-point distributed suppression mode in advance, and gradually activate the distributed suppression modules of different nodes, and at the same time adjust the opening angle before the contacts are disconnected to delay arc generation; if the voltage fluctuates briefly at a low frequency and significantly at certain moments, that is, the fluctuation amplitude exceeds the preset range, and the current fluctuates slowly and periodically, indicating that the system is in a heavy load state, the fluctuation frequency is low but the amplitude is large, then the system recognizes it as a precursor to a low-frequency transient disturbance; when this happens When this happens, the system issues a second-level warning signal, adjusts the charging and discharging time constant of the capacitor absorption to adapt to low-frequency fluctuations, and slows down the speed of the contact opening distance increase; if the voltage and current oscillate rapidly and at a high frequency, and the fluctuation frequency is significantly higher than the steady-state frequency, usually above several thousand hertz, the system identifies it as a precursor to high-frequency oscillation; when this happens, the system issues a third-level warning signal, triggers the low-capacitance absorption operation, dynamically adjusts the current peak delay through a small capacitor and increases the impedance to reduce the oscillation frequency; if the current increases significantly in the current cycle and the voltage is relatively stable, and the current amplitude rises rapidly, the system identifies it as a precursor to a current impact event; when this happens, the system issues a fourth-level warning signal, adds a high-impedance access step before the switch is opened, and immediately adjusts the contact disconnection angle. If the voltage and current fluctuate repeatedly in the current cycle, the frequency is high, and the number of changes exceeds the preset standard, the system identifies it as a precursor to multiple transient disturbances; when this happens, the system issues a fifth-level warning signal, gradually guides the overvoltage energy to disperse in the low-frequency direction, and controls the change in the contact opening distance to maintain a relatively stable increase rate.

[0067] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0068] Example 2

[0069] The second embodiment of the present invention is different from the previous embodiment in that:

[0070] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0071] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0072] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0073] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0074] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0075] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for suppressing overvoltage during circuit breaker opening operation, characterized in that: include, During the opening operation, monitor the transient voltage changes at each key node of the system; Select a distributed multi-point suppression method based on the node voltage status, and adjust the circuit breaker opening angle based on the voltage and current status detected in real time; In the event of transient overvoltage, the line impedance is instantaneously adjusted to delay the voltage rise, and a small capacitor is added to the trip circuit to absorb the transient voltage; Based on the fault feature analysis of the line, it warns of impending overvoltage and triggers adaptive adjustment operations.

2. The overvoltage suppression method for circuit breaker opening operation according to claim 1, characterized in that: The key nodes include bus nodes, branch nodes, transformer interface nodes, load end nodes, and circuit breaker contact nodes.

3. The overvoltage suppression method for circuit breaker opening operation according to claim 2, characterized in that: The monitoring system includes monitoring the transient voltage changes of each key node of the system by distributed monitoring of the voltage amplitude and phase of each key node to obtain the transient voltage changes of each key node. The distributed monitoring system uses high-precision sensors to collect voltage and phase data at each key node and transmits it to the central control system to form a multi-node transient voltage database; The central control system determines the voltage fluctuation characteristics of each node based on real-time transient data analysis to determine the key node locations where overvoltage may occur during the opening operation. When the opening operation is performed, the corresponding suppression position is selected according to the monitored transient voltage data and the multi-point suppression operation is triggered synchronously, so that the suppression module of each node responds to the operation instruction within the selected time node.

4. The overvoltage suppression method for circuit breaker opening operation according to claim 3, characterized in that: The multi-point suppression method includes, during the multi-point suppression process, the central control system sets the response timing of each node according to the voltage fluctuation and phase difference of each key node; The central control system analyzes the transient voltage change trend during the opening operation and assigns different response delays to each node to form a distributed response sequence. Each node receives the suppression instruction according to the preset response sequence and performs voltage adjustment and load adjustment in turn, thereby controlling the propagation of overvoltage waves during the opening process. By gradually activating adjacent nodes to perform multi-point coordinated suppression operations, the energy of the voltage wave is transmitted layer by layer along the suppression nodes, achieving a phased dispersion of the overvoltage energy. At the same time, the coordinated response between the nodes is kept consistent through timing control. During the opening operation, the overvoltage energy at different locations is gradually decomposed and transferred to the next-level node until the global multi-point response chain is completed.

5. The overvoltage suppression method for circuit breaker opening operation according to claim 4, characterized in that: The real-time detection includes high-frequency sampling of the current polarity, residual voltage amplitude and polarity difference of the line voltage in the line, capturing the instantaneous direction change of the current in the line through the current sensor, analyzing the polarity and identifying the moment when the current is close to the zero crossing point, and at the same time, the detection system records the instantaneous amplitude of the residual voltage to obtain the distribution of the residual energy on the line; The voltage polarity is detected by collecting waveform data in real time through the voltage sensor, comparing the voltage polarity difference before and after the opening of the switch, and determining the phase relationship between the current and voltage. At the moment when the contact opening distance reaches the maximum value, the central controller selects a specific opening angle and adjusts the triggering timing of the opening according to the polarity difference of the current and voltage.

6. The overvoltage suppression method for circuit breaker opening operation according to claim 5, characterized in that: The instantaneous voltage absorption includes connecting a small capacitor to the switch-off circuit and controlling the charge and discharge rate of the capacitor during the current fluctuation by dynamically adjusting the charge and discharge time constant, wherein the adjustment of the time constant is based on the instantaneous characteristics of the current and voltage waveforms, so that the capacitor gradually reaches a preset charge state before the current peak occurs, and releases the stored charge during the current drop; After the switch is opened, the capacitor in the circuit gradually absorbs and releases charges, changing the transient response characteristics of the circuit. The oscillation frequency gradually changes from the original high frequency to a low frequency to adapt to the impedance change of the circuit and control the amplitude of the current fluctuation.

7. The overvoltage suppression method for circuit breaker opening operation according to claim 6, characterized in that: The fault characteristic analysis of the line includes combining historical data analysis with real-time collected information to comprehensively analyze the fault characteristics in the line; A fault feature library is built based on historical operating data, which includes voltage and current change trends and fluctuation frequency parameters under different working conditions. During real-time monitoring, the waveform characteristics of the current voltage and current are continuously compared with the data in the fault feature library, the similarity is analyzed and abnormal changes are detected. By calculating the instantaneous deviation and fluctuation rate of the current waveform, potential overvoltage precursor characteristics are identified. After identifying the precursor characteristics, the system generates a warning signal to indicate that a possible overvoltage state is about to occur and starts the preparation process for the tripping suppression step.

8. The overvoltage suppression method for circuit breaker opening operation according to claim 7, characterized in that: The triggering of the adaptive adjustment operation includes: if the voltage rises rapidly and the amplitude significantly exceeds the rated voltage level in the current cycle, while the current fluctuates slightly or remains below the preset level, and the fluctuation frequency is higher than the preset standard and frequent sudden increases occur, the system recognizes it as a precursor to a high voltage event; when this happens, the system will issue a first-level early warning signal, start the multi-point distributed suppression mode in advance, and gradually activate the distributed suppression modules of different nodes, and at the same time adjust the opening angle before the contacts are disconnected to delay arc generation; if the voltage fluctuates briefly at a low frequency and significantly at certain moments, that is, the fluctuation amplitude exceeds the preset range, and the current fluctuates slowly and periodically, indicating that the system is in a heavy load state, the fluctuation frequency is low but the amplitude is large, then the system recognizes it as a precursor to a low-frequency transient disturbance; when this happens When this happens, the system issues a second-level warning signal, adjusts the charging and discharging time constant of the capacitor absorption to adapt to low-frequency fluctuations, and slows down the speed of the contact opening distance increase; if the voltage and current oscillate rapidly and at a high frequency, and the fluctuation frequency is significantly higher than the steady-state frequency, usually above several thousand hertz, the system identifies it as a precursor to high-frequency oscillation; when this happens, the system issues a third-level warning signal, triggers the low-capacitance absorption operation, dynamically adjusts the current peak delay through a small capacitor and increases the impedance to reduce the oscillation frequency; if the current increases significantly in the current cycle and the voltage is relatively stable, and the current amplitude rises rapidly, the system identifies it as a precursor to a current impact event; when this happens, the system issues a fourth-level warning signal, adds a high-impedance access step before the switch is opened, and immediately adjusts the contact disconnection angle. If the voltage and current fluctuate repeatedly in the current cycle, the frequency is high, and the number of changes exceeds the preset standard, the system identifies it as a precursor to multiple transient disturbances; when this happens, the system issues a fifth-level warning signal, gradually guides the overvoltage energy to disperse in the low-frequency direction, and controls the change in the contact opening distance to maintain a relatively stable increase rate.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 8 are implemented.

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