Method and system for configuring grading capacitor of GIS double-break vacuum circuit breaker based on multiple reignition transient overvoltage characteristics

Abstract

The application discloses a GIS double-break vacuum circuit breaker based on multiple reignition transient overvoltage characteristics and a voltage-sharing capacitor configuration method and system, and establishes a breaking transient simulation model of the double-break vacuum circuit breaker; simulates transient processes of multiple breaking small inductance current of the vacuum circuit breaker under different ground stray capacitances and different voltage-sharing capacitors; when the breaking point is in a reignition state, according to transient overvoltage peak values borne by the high-potential end breaking point and the low-potential end breaking point, takes the voltage-sharing capacitor first meeting a set voltage-sharing criterion as a lower limit of an optimal configuration interval of the voltage-sharing capacitor, takes the voltage-sharing capacitor meeting a set negative effect criterion as an upper limit of the optimal configuration interval of the voltage-sharing capacitor; takes a weighted sum of the lower limit and the upper limit of the optimal configuration interval of the voltage-sharing capacitor as a voltage-sharing capacitor optimal value; and under a transient performance constraint condition, corrects the voltage-sharing capacitor optimal value to determine a voltage-sharing capacitor configuration value.

Description

Technical Field

[0001] This invention relates to the field of power system switchgear technology, specifically to a method and system for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage. Background Technology

[0002] As high-voltage gas-insulated metal-enclosed switchgear (GIS) develops towards environmental protection and low carbon emissions, the use of environmentally friendly gas insulation combined with vacuum arc-extinguishing technology has become a viable alternative. One of the important routes. To meet the ultra-high voltage withstand requirements, vacuum circuit breakers often adopt a double-break series structure.

[0003] Existing technologies consider the thermal breaking capacity of circuit breakers and use short-circuit faults as voltage equalization verification scenarios. However, for vacuum circuit breakers, whose core advantage lies in dielectric recovery speed, the extremely high TRV rise rate and multiple reignitions caused by breaking small inductive currents are the core factors affecting breaking performance. When breaking small inductive currents, the arc is easily cut off before the natural zero crossing. If the break point cannot withstand the transient recovery voltage (TRV), multiple reignitions will occur, leading to dangerous multiple reignition-induced overvoltages. Furthermore, stray capacitances within the equipment can cause uneven voltage distribution between the break points, with the high-voltage side break point experiencing excessively high transient overvoltages, which severely affects the breaking performance and operational reliability of the circuit breaker.

[0004] Existing technologies often employ parallel voltage-equalizing capacitors to improve voltage distribution at the break point. However, for GIS equipment using various new environmentally friendly insulating media such as clean air, C4F7N, and C5F10O, the stray capacitance network changes due to differences in dielectric properties and structural size adjustments under different insulation strengths. This leads to complex coupling relationships with transient overvoltages during breaking, making it difficult to determine the effective boundary of the voltage-equalizing capacitors. Traditional voltage-equalizing capacitor configuration methods, based solely on the voltage-equalizing characteristics at the break point, are prone to improper configuration, potentially resulting in increased equipment size, increased transient overvoltages, and decreased economic efficiency, failing to meet the safe and reliable operation requirements of environmentally friendly GIS equipment. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method and system for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage. The equalizing capacitors are configured according to the characteristics of multiple reignition overvoltage when interrupting small inductive current loads. Specifically for environmentally friendly GIS double-break vacuum circuit breakers, under small inductive current interruption conditions, the influence of different environmentally friendly insulating media on the circuit breaker's multiple reignition transient overvoltage is clarified. This allows for a comprehensive consideration of the equalizing effect of the double-break design and the suppression effect of multiple reignition transient overvoltage, determining the optimal configuration range of the equalizing capacitors under multi-factor constraints, thereby improving the interruption reliability of the double-break vacuum circuit breaker.

[0006] The present invention adopts the following technical solution.

[0007] This invention proposes a method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage. The GIS uses an environmentally friendly insulating medium, which includes a variety of component gases. The methods include: Obtain the parameter range of stray capacitance to ground for GIS using different environmentally friendly insulating media; A transient simulation model of a double-break vacuum circuit breaker is established, which includes a high-potential break on the power supply side, a low-potential break on the load side, and a stray capacitance to ground connected in parallel to the low-potential break that satisfies the parameter range. Based on the transient simulation model of interruption, the transient process of a vacuum circuit breaker interrupting small inductor current multiple times under different stray capacitances to ground and different voltage equalization capacitors is simulated. When the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end detect that the break is in the reignition state, according to the peak value of the transient overvoltage borne by the high-potential end and the low-potential end, the voltage equalization capacitor that first meets the set voltage equalization criterion is taken as the lower limit of the optimal configuration range of the voltage equalization capacitor, and the voltage equalization capacitor that meets the set negative effect criterion is taken as the upper limit of the optimal configuration range of the voltage equalization capacitor. The weighted sum of the lower and upper limits of the optimal configuration range of the voltage equalizing capacitor is used as the preferred value of the voltage equalizing capacitor; under transient performance constraints, the preferred value of the voltage equalizing capacitor is modified to determine the configuration value of the voltage equalizing capacitor.

[0008] Preferably, at a rated gas pressure of 0.7 MPa The scheme is used as the benchmark scheme, and the benchmark insulation strength is denoted as . , No. The insulation strength of environmentally friendly insulating media is Based on the principle of equivalent insulation, the insulation distance compensation amount for GIS using environmentally friendly insulating media is calculated. :

[0009] In the formula, The equivalent insulation distance for the baseline scheme, For the first Equivalent insulation distance for environmentally friendly insulating media solutions; Based on the GIS insulation distance compensation, the stray capacitance to ground of GIS with different environmentally friendly insulation media is calculated using finite element simulation to obtain the stray capacitance parameter range. , and These represent the minimum and maximum values ​​of stray capacitance to ground under different environmentally friendly insulating media.

[0010] Preferably, a transient simulation model of the breaking state of a double-break vacuum circuit breaker is established, including: An equivalent circuit for a double-break vacuum circuit breaker is established. The equivalent circuit includes a high-potential break and a low-potential break connected in series. The inter-electrode capacitance and equalizing capacitance of the high-potential break are connected in parallel with the high-potential break. The inter-electrode capacitance, equalizing capacitance, and stray capacitance to ground of the low-potential break are all connected in parallel with the low-potential break. The stray capacitance to ground meets the parameter range. The high-potential break and the low-potential break are equivalent to ideal switches. One end of the high-potential break is connected to the system power supply side, and the other end of the high-potential break is connected to one end of the low-potential break. The other end of the low-potential break is connected to the load side. Separate logic control modules are established for the high-potential break and the low-potential break. In the equivalent circuit, the high-potential break logic control module takes the current, power supply voltage, and load voltage of the high-potential break as input signals and the opening or closing of the high-potential break as output signals; the low-potential break logic control module takes the current, power supply voltage, and load voltage of the low-potential break as input signals and the opening or closing of the low-potential break as output signals. Both the high-potential and low-potential break logic control modules include: a current-cutting judgment unit, a reignition judgment unit, and a high-frequency arc-extinguishing judgment unit. The interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end are combined with the equivalent circuit topology to form the interruption transient simulation model of the dual-break vacuum circuit breaker.

[0011] Preferably, the current-cutting judgment unit is used to determine the transient recovery voltage of the high-potential end break and the low-potential end break in the equivalent circuit. , Inversely inferring the current before the circuit breaker is interrupted ,when hour Then it is determined that the flow has been blocked at the break point. The set interception threshold, For simulation time variables, This is the trigger time for the tripping command; The reignition detection unit is used to compare the transient recovery voltages of the high-potential and low-potential breaks in the equivalent circuit. , The transient pressure-bearing capacity of the medium at each fracture point is considered to be greater than the transient pressure-bearing capacity of the medium at the fracture point, and reignition is determined to have occurred. The high-frequency arc extinction judgment unit is used when the reignition judgment unit determines that reignition has occurred and the high-frequency oscillation stage after reignition has begun. If the high-frequency arc is extinguished, it is determined that the arc is extinguished; otherwise, the arc is not extinguished. The set threshold for high-frequency arc extinguishing capability; The real-time current at the break point, when =1 represents the real-time current at the high-potential break point. ,when =2 represents the real-time current at the low-potential break point. .

[0012] Preferably, during the transient process, if the simulation time does not exceed the set reignition determination period, the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end cyclically execute the current cutting-off, reignition, and arc extinction status judgments of the break points, including: 1) If the current throttling judgment unit determines that current throttling has occurred, the opening logic control module of the high potential end break and the opening logic control module of the low potential end break will both send the opening control signal to the corresponding break. 2) The simulation ends when the simulation time exceeds the set re-ignition determination period. If the simulation time does not exceed the set re-ignition determination period but the re-ignition is not determined, the re-ignition status judgment is executed repeatedly until the simulation time exceeds the set re-ignition determination period. If the simulation time does not exceed the set re-ignition determination period and the re-ignition is determined, the opening logic control module of the high potential terminal and the opening logic control module of the low potential terminal both send a closing control signal to the corresponding terminal. 3) Execute the arc extinction judgment. If the arc is determined to be extinguished, the opening logic control module of the high potential end and the opening logic control module of the low potential end both send the opening control signal to the corresponding end and return to 2); if the arc is determined not to be extinguished, the arc extinction status judgment is executed cyclically.

[0013] Preferably, in the transient simulation model of breaking, the initial value of the equalizing capacitor is set, and the value is increased according to the set step size. Repeated simulation is performed for the stray capacitance to ground under the same type of environmentally friendly insulating medium. The transient overvoltage waveform of the double-break vacuum circuit breaker during the current cutting and multiple reignition processes is extracted, and the peak value of the transient overvoltage borne by the high potential end break and the low potential end break is recorded. Calculate the voltage averaging coefficient using the peak transient overvoltages borne by the two breaks. As shown in the following formula:

[0014] In the formula, , These represent the peak transient overvoltages borne by the high-potential and low-potential break points, respectively.

[0015] Preferably, the equalization criterion is set as follows:

[0016] In the formula, The equalization sensitivity threshold, This represents the change in the equal pressure coefficient. This represents the change in the voltage equalization capacitance. It is the absolute ratio of the change in the equalizing coefficient to the change in the equalizing capacitance.

[0017] Preferably, the negative effect criterion is set as follows: ,

[0018] In the formula, This represents the maximum transient overvoltage peak value at the high-potential end of the circuit during multiple reignitions in the high-frequency oscillation phase, obtained through simulation under a set of equalizing capacitors. This represents the change in the equalizing capacitance.

[0019] Preferably, the optimal configuration range of the equalizing capacitor for GIS double-break vacuum circuit breakers under different environmentally friendly insulating media. , It is a voltage equalization capacitor. This represents the lower limit of the optimal configuration range for the voltage-equalizing capacitors. This represents the upper limit of the optimal configuration range for the voltage-equalizing capacitors.

[0020] In the formula, The preferred value for the voltage equalization capacitor is... , All are weights. + =1.

[0021] Preferably, when the optimization objectives are to minimize the deviation of the equalization coefficient from 1, minimize the equipment volume, and minimize the equipment cost, > ; When the optimization objectives are to minimize the transient overvoltage at the high-potential end, the transient overvoltage at the low-potential end, and the number of reignitions, < ; When the optimization objectives are to minimize the deviation of the equalization coefficient from 1, minimize the equipment volume, minimize the equipment cost, minimize the transient overvoltage at the high potential end of the break, minimize the transient overvoltage at the low potential end of the break, and minimize the number of reignitions, = .

[0022] Preferably, the transient performance constraints include: 1) The peak transient recovery voltage of the double-break vacuum circuit breaker during multiple reignition processes does not exceed the national standard's allowable rated operating impulse withstand voltage: 2) The peak value of transient overvoltage of the load during multiple reignition processes does not exceed the national standard allowable rated operating impulse withstand voltage; 3) The equalization coefficient is not higher than the set equalization threshold.

[0023] Another aspect of this invention proposes a voltage equalization capacitor configuration system for a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, comprising: The simulation model building module is used to obtain the parameter range of the stray capacitance to ground of GIS using different environmentally friendly insulation media; and to build a transient simulation model of the breaking of a double-break vacuum circuit breaker, wherein the model includes the high-potential break on the power supply side, the low-potential break on the load side, and the stray capacitance to ground that meets the parameter range and is connected in parallel to the low-potential break. The uniform capacitor configuration module is used to simulate the transient process of a vacuum circuit breaker repeatedly interrupting small inductor currents under different stray capacitances to ground and different equalizing capacitors, based on the transient simulation model of interruption. When the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end detect that the break is in a reignition state, the equalizing capacitor that first meets the set equalizing criterion is used as the lower limit of the optimal configuration range of the equalizing capacitor, and the equalizing capacitor that meets the set negative effect criterion is used as the upper limit of the optimal configuration range of the equalizing capacitor, based on the peak value of the transient overvoltage borne by the high-potential end and the low-potential end. The weighted sum of the lower limit and the upper limit of the optimal configuration range of the equalizing capacitor is used as the preferred value of the equalizing capacitor. Under the transient performance constraints, the preferred value of the equalizing capacitor is corrected to determine the configuration value of the equalizing capacitor.

[0024] The present invention is also a terminal, including a processor and a storage medium; the storage medium is used to store instructions; the processor is used to perform operations according to the instructions to execute the steps of the method.

[0025] The present invention is also a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method.

[0026] The beneficial effects of this invention are that, compared with the prior art, it includes at least the following: This invention proposes a method for configuring voltage-equalizing capacitors that takes into account the impact of environmentally friendly insulating dielectric substitution, using clean air, C4F7N, and C5F... 10 The changes in equipment structure compensation and stray capacitance to ground caused by the replacement of environmentally friendly media such as O are incorporated into the configuration of equalizing capacitors, forming a unified configuration approach applicable to different environmentally friendly media conditions. This invention is more applicable to the design of equalizing capacitors under different environmentally friendly insulation conditions, and can provide a clearer basis for engineering selection and verification.

[0027] This invention incorporates the impact of multiple reignition overvoltage characteristics during the breaking process of a double-break vacuum circuit breaker into the voltage equalization design. It not only considers the static voltage distribution of the breaks but also the transient recovery voltage changes and high-frequency oscillation characteristics of the circuit breaker during the breaking process. The transient overvoltage and reignition process are used as important bases for the configuration of the voltage equalization capacitors. Compared with the traditional method of capacitor design from the perspective of static voltage equalization, this invention can more comprehensively reflect the characteristics of the transient breaking process of the double-break vacuum circuit breaker, making the voltage equalization capacitor configuration results more in line with engineering practice.

[0028] This invention optimizes the voltage-equalizing capacitor configuration strategy for the harsh operating condition of small inductor current interruption. Specifically targeting small inductor current interruption scenarios prone to current cutoff, multiple reignitions, and peak overvoltages, it optimizes the parallel voltage-equalizing capacitors to better adapt to voltage distribution requirements under high-frequency transient processes. Traditional voltage-equalizing designs based on short-circuit fault interruption conditions fail to reflect the true weak points in the insulation of vacuum circuit breakers. This invention focuses on the more sensitive operating conditions of switching equipment, reducing the probability of reignition and overvoltage amplitude under extreme transient conditions, thus improving the interruption reliability of the circuit breaker.

[0029] This invention proposes a constraint mechanism that combines voltage equalization effect with overvoltage negative effect. By setting a saturation point for voltage equalization effect and a highlighting point for overvoltage negative effect, the optimal configuration range for voltage equalization capacitors is given, so that capacitor selection no longer relies solely on a single voltage equalization coefficient. Compared with conventional configuration methods that rely on experience for capacitor selection and lack clear upper limit constraints, this invention can avoid the problems of increased energy storage and overvoltage rise caused by excessively large capacitors, while also preventing poor voltage equalization effect caused by insufficient capacitors. It provides clearer upper and lower limit criteria for engineering design, improving the safety, reliability, and economy of the solution. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the equivalent circuit for a double-break vacuum circuit breaker to interrupt an inductive low-current load, as established in this invention. Figure 2This is a graph showing the variation of the equalization coefficient of a double-break vacuum circuit breaker under different equalization capacitance conditions when using C4F7N / CO2 mixed gas as the insulating medium. It is used to illustrate the improvement law of the equalization effect with the increase of capacitance and its saturation inflection point. Figure 3 This invention presents the variation curves of transient overvoltage during multiple reignitions of a double-break vacuum circuit breaker under different equalizing capacitor conditions when using C4F7N / CO2 mixed gas as the insulating medium. These curves illustrate the influence trend of equalizing capacitor energy storage on the peak transient voltage and the prominence of the negative overvoltage effect. Figure 4 This invention provides the optimal configuration range of the equalizing capacitor obtained under different ratios of C4F7N / CO2 mixed gas insulation conditions, which is used to demonstrate the coupling relationship between the insulation strength of the environmentally friendly gas, the change of stray capacitance, and the configuration range of the equalizing capacitor. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The embodiments of the present invention described and shown in the accompanying drawings can generally be combined in various other ways.

[0032] This invention proposes a method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage. The GIS uses an environmentally friendly insulating medium, which includes a variety of component gases. The methods include: Step 1: Obtain the parameter range of stray capacitance to ground for GIS using different environmentally friendly insulating media.

[0033] In a preferred but non-limiting embodiment of the invention, at a rated gas pressure of 0.7 MPa The solution serves as a benchmark, targeting clean air, , Various new environmentally friendly insulating media are used, and their differences in dielectric properties and insulation strength are considered. Based on the principle of equivalent insulation strength, the compensation amount for key insulation dimensions of GIS equipment is calculated. Then, the stray capacitance parameter range to ground is extracted from the compensated geometry. The purpose of this step is to uniformly map the structural changes caused by the replacement of environmentally friendly insulating media into stray capacitance changes, providing boundary conditions for subsequent voltage equalization capacitor configuration.

[0034] Step 1.1: Obtain the relative permittivity and insulation strength of the environmentally friendly insulating medium.

[0035] Specifically, the baseline scheme is based on a rated gas pressure of 0.7 MPa. Insulation scheme, denoted as the reference insulation strength as The reference relative permittivity is The reference-to-ground stray capacitance is For the first The relative permittivity of environmentally friendly insulating media is Insulation strength is Stray capacitance to ground is .

[0036] If the environmentally friendly insulating medium is a mixture of gases, the equivalent relative permittivity is as follows:

[0037] In the formula, and The first The relative permittivity of the first and second component gases in environmentally friendly insulating media. For the first component gas in the The mixing ratio in environmentally friendly insulating media.

[0038] Step 1.2: Based on the principle of equivalent insulation, calculate the insulation distance compensation amount of GIS using environmentally friendly insulation media.

[0039] When the insulation strength of the environmentally friendly insulating medium changes, the dimensions of the GIS structure need to be compensated based on the insulation strength of the environmentally friendly insulating medium, while keeping the rated gas pressure constant at 0.7 MPa.

[0040] Specifically, based on the equivalent insulation principle of gas discharge, under the same withstand voltage conditions, the benchmark scheme and the environmentally friendly insulating medium scheme should meet the following requirements:

[0041]

[0042] In the formula, The equivalent insulation distance for the baseline scheme, For the first Equivalent insulation distance for environmentally friendly insulating media solutions.

[0043] The first The insulation distance compensation amount of GIS equipment under environmentally friendly insulating media is denoted as: Then we have:

[0044] Characterizing environmentally friendly insulating dielectric replacement Subsequently, the critical insulation distance of the GIS equipment needs to be increased to ensure insulation margin.

[0045] Understandably, the lower the insulation strength of the environmentally friendly insulating medium, the... The larger the value, the more significant the compensation adjustment will be in the internal structural dimensions of the GIS. This compensation amount directly determines the subsequent trend of stray capacitance to the ground.

[0046] Step 1.3: Based on the GIS insulation distance compensation amount, calculate the GIS-to-ground stray capacitance for different environmentally friendly insulation media through finite element simulation to obtain the stray capacitance parameter range.

[0047] Specifically, after GIS insulation distance compensation, a system using the first... A three-dimensional electric field model of GIS equipment using environmentally friendly insulating media was constructed, and the model was solved using finite element electrostatic field simulation software to extract the local capacitance and equivalent stray capacitance to ground of key components. During the simulation, the insulation distance after structural compensation, conductor dimensions, shell radius, and dielectric parameters of the environmentally friendly insulating media were used as input boundary conditions. The stray capacitance to ground under corresponding operating conditions was obtained by numerically solving the electric field distribution. Therefore, the third... The stray capacitance to ground of GIS corresponding to environmentally friendly insulating media is denoted as .

[0048] Furthermore, regarding clean air, , By adjusting the proportions of each component gas, dielectric parameters, and corresponding insulation compensation conditions using different environmentally friendly insulating media, finite element electrostatic field simulations were performed to obtain the stray capacitance to ground under different operating conditions. By scanning multiple sets of simulation results for different environmentally friendly insulating media and under different insulation compensation conditions, the parameter range of the stray capacitance to ground can be obtained.

[0049] in, and These represent the minimum and maximum values ​​of stray capacitance to ground under different environmentally friendly insulating media. This parameter range reflects the overall range of changes in the internal electric field distribution and stray capacitance of GIS after the replacement of the environmentally friendly insulating media.

[0050] Traditional modeling often treats stray capacitance as a fixed constant, while this invention uses the parameter range of stray capacitance to ground as the input boundary condition for subsequent electromagnetic transient analysis of the dual-break vacuum circuit breaker, so that the transient simulation parameters can simultaneously take into account the changes in gas dielectric properties and stray capacitance caused by GIS structure compensation.

[0051] Step 2: Establish the equivalent circuit of the double-break vacuum circuit breaker. The equivalent circuit includes a high-potential break and a low-potential break connected in series. The inter-electrode capacitance and equalizing capacitance of the high-potential break are connected in parallel with the high-potential break. The inter-electrode capacitance, equalizing capacitance and stray capacitance to ground of the low-potential break are connected in parallel with the low-potential break. The stray capacitance to ground satisfies the parameter range.

[0052] In a preferred but non-limiting embodiment of the present invention, an equivalent circuit of a double-break vacuum circuit breaker is established using electromagnetic transient simulation software, and the small inductance current interruption logic of the vacuum circuit breaker is embedded to accurately simulate the current cut-off, multiple reignition and high-frequency arc extinction processes.

[0053] like Figure 1 As shown, As the system voltage source, , These are the equivalent resistance and inductance on the system power supply side, respectively. This is the equivalent capacitance to ground of the line from the power supply outlet to the circuit breaker. , These are the equivalent inductance and capacitance on the load side, respectively. The equivalent circuit of a two-port vacuum circuit breaker includes: a high-potential break. Low potential end break Inter-electrode capacitance at the high-potential end break Inter-electrode capacitance at the low-potential terminal break Stray capacitance to ground Equalizing capacitor at the high-potential end Equalizing capacitor at the low potential terminal High-potential end break Low potential end break An ideal switch is used as an equivalent; one end of the high-potential break is connected to the system power supply side, the other end of the high-potential break is connected to one end of the low-potential break, the other end of the low-potential break is connected to the load side, the inter-electrode capacitance and voltage equalization capacitance of the high-potential break are connected in parallel with the high-potential break, and the inter-electrode capacitance, voltage equalization capacitance and stray capacitance to ground of the low-potential break are connected in parallel with the low-potential break.

[0054] like Figure 1As shown, when the break is in the steady-state stage before breaking, the voltage distribution across the break is mainly constrained by the capacitor network. After entering the transient breaking process, the voltage distribution between the breaks is determined by the transient recovery voltage, stray capacitance coupling, and the reignition process. Therefore, the equivalent circuit topology established in this invention can comprehensively reflect the dynamic coupling effects of the inter-electrode capacitance, voltage equalization capacitance, and stray capacitance to ground of the two breaks themselves. In the simulation model, the stray capacitance to ground corresponding to different environmentally friendly insulating media is parameterized, enabling the same simulation model to cover various types and compositions of environmentally friendly insulating media, achieving a comparison and analysis of transient voltage characteristics and voltage equalization capacitance compensation effects under different stray capacitance conditions. Furthermore, the equivalent circuit established in this invention considers the compensation effect of stray capacitance to ground; therefore, when calculating the breaking command, the control module incorporates the stray capacitance to ground as a parameter to correct the voltage balance across the breaks and prevent reignition at one break due to uneven voltage distribution.

[0055] Step 3: Establish the interruption logic control module for the high-potential end break and the interruption logic control module for the low-potential end break respectively. In the equivalent circuit, the interruption logic control module for the high-potential end break takes the current, power supply voltage, and load voltage of the high-potential end break as input signals and the opening or closing of the high-potential end break as output signals. The interruption logic control module for the low-potential end break takes the current, power supply voltage, and load voltage of the low-potential end break as input signals and the opening or closing of the low-potential end break as output signals. Both the interruption logic control modules for the high-potential end break and the low-potential end break include: a current throttling judgment unit, a reignition judgment unit, and a high-frequency arc extinction judgment unit.

[0056] like Figure 1 As shown, Function1, the logic control module for breaking the high-potential terminal, acquires the current at the high-potential terminal. The power supply side voltage of the high-potential terminal disconnection and the load-side voltage of the high-potential terminal break The high-potential terminal disconnection logic control module sends a control signal to the high-potential terminal disconnection to either open or close. The low-potential terminal interruption logic control module Function2 obtains the current at the low-potential terminal interruption. The power supply side voltage at the low potential terminal break and the load-side voltage of the low-potential terminal break The low-potential terminal interruption logic control module sends an open or closed control signal to the low-potential terminal interruption. .

[0057] Specifically, such as Figure 1 As shown, in the equivalent circuit containing stray capacitance to ground, the intermediate node potential... Represented as:

[0058] Therefore, the transient recovery voltages of the high-potential and low-potential breaks can be expressed as follows:

[0059]

[0060] In the formula, , These are the transient recovery voltages at the high-potential and low-potential ends of the break, respectively.

[0061] Furthermore, both interruption logic control modules have the same structure, including: a current throttling judgment unit, a reignition judgment unit, and a high-frequency arc extinction judgment unit; The current-cutting judgment unit is used to determine the transient recovery voltage of the high-potential and low-potential breaks in the equivalent circuit. , Inversely inferring the current before the circuit breaker is interrupted ,when hour Then it is determined that the flow has been blocked at the break point. The set interception threshold, For simulation time variables, This is the trigger time for the tripping command; After a circuit breaker interrupts a fault current, the transient recovery voltage (TRV) waveform appearing across its terminals fully encodes crucial information about the current prior to interruption. By accurately measuring the TRV, the current prior to interruption can be inferred. The current throttling judgment unit has a built-in current early zero-crossing criterion. When the current early zero-crossing criterion is met, the current throttling judgment unit determines that the break point has throttled.

[0062] The reignition detection unit is used to determine whether reignition has occurred based on the comparison between the transient recovery voltage of the high-potential end and the low-potential end of the fracture surface and the transient pressure-bearing capacity of the medium at the fracture surface. The reignition judgment unit has a built-in reignition criterion, as shown in the following formula: ,

[0063] In the formula, The transient recovery voltage of the break point. The transient pressure-bearing capacity of the fracture medium. The initial breakdown voltage, The rate of change of the strength of the insulating medium. This indicates the time period after the circuit breaker is tripped.

[0064] When the reignition criterion is met, the reignition judgment unit determines that reignition has occurred at the break point.

[0065] The high-frequency arc extinction judgment unit is used to determine whether the high-frequency arc has been extinguished based on the rate of change of the real-time current at the break point when the reignition judgment unit determines that reignition has occurred and the high-frequency oscillation stage after reignition has begun.

[0066] The high-frequency arc extinction judgment unit has a built-in high-frequency arc extinction criterion, as shown in the following formula:

[0067] In the formula, The set threshold for high-frequency arc extinguishing capability; The real-time current at the break point, when =1 represents the real-time current at the high-potential break point. ,when =2 represents the real-time current at the low-potential break point. ; When the high-frequency oscillation stage after reignition is reached and the high-frequency arc extinction criterion is met, the high-frequency arc extinction judgment unit determines that the arc is finally extinguished during the high-frequency oscillation process; if it is not extinguished, it indicates that the arc has reignited, and the process returns to execute the current cutoff and reignition judgment. This applies as long as the simulation time falls within the reignition judgment period. Inside, the process will continuously execute the judgments of current cut-off, reignition, and arc extinction.

[0068] Step 4: The interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end are combined with the equivalent circuit topology to form the interruption transient simulation model of the dual-break vacuum circuit breaker. Based on the transient simulation model of interruption, the transient process of multiple interruptions of small inductor currents by a vacuum circuit breaker under different stray capacitances to ground and different equalizing capacitors is simulated. During the transient process, if the simulation time does not exceed the set reignition judgment period, the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end will cyclically execute the current cut-off, reignition and arc extinction status judgment of the break.

[0069] The equivalent circuit utilizes the high-potential end break-off logic control module and the low-potential end break-off logic control module to simulate the multiple break-off transient process of a small inductor current. The break-off logic control module is not only used to determine whether the break-off current crosses zero, whether the break-off transient recovery voltage exceeds the dielectric recovery strength, and whether the arc is finally extinguished, but also further uses the intermediate node potential, the double-break voltage divider result, and the transient recovery voltage output by the equivalent circuit topology including stray capacitance to ground as criterion inputs, so that the stray capacitance to ground directly participates in the arc extinguishing process judgment by changing the break-off voltage divider state.

[0070] The stray capacitance to ground is used as an input parameter of the equivalent circuit to control two interruption logic control modules to simulate the transient process of a vacuum circuit breaker interrupting a small inductor current under different stray capacitances to ground. During the transient process, if the simulation time does not exceed the set reignition judgment period, the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end cyclically execute the status judgment of current cutting, reignition, and arc extinction of the break, specifically including: 1) If the current throttling judgment unit determines that current throttling has occurred, both the high-potential end break-opening logic control module and the low-potential end break-opening logic control module will send an opening control signal to the corresponding break-opening point, i.e. =0, =0; 2) The simulation ends when the simulation time exceeds the set reignition determination period. If the simulation time does not exceed the set reignition determination period but reignition is not determined, the reignition status judgment is executed repeatedly until the simulation time exceeds the set reignition determination period. If the simulation time does not exceed the set reignition determination period and reignition is determined, both the high-potential terminal break-opening logic control module and the low-potential terminal break-opening logic control module send a closing control signal to the corresponding break point. =1, =1; 3) Perform an arc extinction judgment. If arc extinction is determined, both the high-potential end break-opening logic control module and the low-potential end break-opening logic control module send an opening control signal to the corresponding break-opening point. =0, =0, and return 2); if it is determined that the arc is not extinguished, the arc extinguishing status judgment is executed repeatedly.

[0071] When a small inductive current is interrupted, phenomena such as current cutoff, reignition, and high-frequency oscillation occur. Therefore, ideal switches are used at both the high-potential and low-potential ends of the circuit breaker, and the interruption logic control module controls the corresponding ideal switches. Through the interruption logic control module, the dynamic transient process of a vacuum circuit breaker interrupting a small inductive current can be reproduced in simulation. Specifically, the stray capacitance to ground participates in the formation of the reignition criterion after current cutoff by changing the intermediate node potential, the voltage divider at the circuit breaker, and the transient recovery voltage, and further affects the subsequent high-frequency arc extinction process.

[0072] In this simulation model, each switching between current throttling, reignition, and arc extinction states is updated in real time based on the voltage distribution results including stray capacitance to ground, thus forming a closed-loop coupling between stray capacitance to ground and the physical arc extinguishing process of the circuit breaker. This model allows for the acquisition of transient overvoltage characteristics under different stray capacitances to ground and different voltage-equalizing capacitors, providing a simulation basis for determining the optimal configuration range of the voltage-equalizing capacitors.

[0073] Step 5: When the interruption logic control module of the high-potential end break and the interruption logic control module of the low-potential end break detect that the break is in the reignition state, based on the transient overvoltage peak value borne by the high-potential end break and the low-potential end break, the voltage equalization capacitor that first meets the set voltage equalization criterion is taken as the lower limit of the optimal configuration range of the voltage equalization capacitor, and the voltage equalization capacitor that meets the set negative effect criterion is taken as the upper limit of the optimal configuration range of the voltage equalization capacitor.

[0074] The equivalent circuit of the vacuum circuit breaker, the interruption logic control module of the high-potential end, and the interruption logic control module of the low-potential end are combined to obtain the interruption transient simulation model. Based on the interruption transient simulation model, the voltage division characteristics of the double-break under different voltage equalization capacitors are analyzed under different environmentally friendly insulating media and the voltage equalization effect saturation point is determined.

[0075] In a preferred but non-limiting embodiment of the present invention, by gradually increasing the voltage equalization capacitor and substituting the values ​​of the stray capacitance to ground corresponding to different environmentally friendly insulating media into the established transient simulation model of the breaking, the variation law of the voltage distribution of the double-break is obtained, thereby obtaining the critical inflection point at which the voltage equalization effect reaches saturation, providing a basis for subsequently determining the configuration range.

[0076] Specifically, step 5 includes: Step 5.1: During the transient process, obtain the peak value of transient overvoltage borne by the high-potential end and low-potential end of the double-break vacuum circuit breaker under the same stray capacitance to ground, different equalizing capacitors, and multiple reignition processes.

[0077] In the established transient simulation model, the initial value of the equalizing capacitor is set, and the value is gradually increased according to the set step size. The simulation of stray capacitance to ground under the same environmentally friendly insulating medium condition is repeated. The small inductor current interruption simulation is executed in sequence. The transient overvoltage waveforms during the current cutting and multiple reignition processes of the double-break vacuum circuit breaker are extracted, and the peak values ​​of the transient overvoltage borne by the high-potential end break and the low-potential end break are recorded. , .

[0078] Adjusting the value of stray capacitance to ground is equivalent to obtaining environmentally friendly insulating media with different components, such as... Figure 2 In The percentages were 2%, 5%, 7%, 10%, 15%, and 20%, respectively.

[0079] Step 5.2: Calculate the voltage equalization coefficient using the peak transient overvoltage borne by the two breaks. The following formula is used to evaluate the uniformity of voltage distribution in a double-break system:

[0080] when The closer the value is to 1, the more uniform the voltage distribution between the two breaks. When A large value indicates a significant voltage distribution deviation due to the shunting effect of stray capacitance to ground. The values ​​calculated under different voltage-equalizing capacitor conditions are statistically analyzed. Plot the curve of the equalization coefficient as a function of the equalization capacitance. Figure 2 To use different components / The equalization coefficient of a mixed gas under different equalization capacitances.

[0081] Step 5.3: The voltage equalization capacitor corresponding to the absolute ratio of the change in voltage equalization coefficient to the change in voltage equalization capacitor when the voltage equalization criterion is first met is taken as the voltage equalization effect saturation point, and the voltage equalization effect saturation point is taken as the lower limit of the optimal configuration range of voltage equalization capacitor.

[0082] analyze Figure 2 As shown by the curve, when the equalizing capacitor is small, its capacitive reactance is comparable to the stray capacitance to ground. Increasing the equalizing capacitor will significantly weaken the shunting effect of the stray capacitance, and the equalizing coefficient will decrease rapidly. However, as the equalizing capacitor further increases to a level far exceeding the influence of the stray capacitance, the voltage at the break point has basically reached equilibrium. The improvement in the equalizing effect from further increasing the equalizing capacitor is significantly reduced, showing a marginal decreasing trend. Therefore, the equalizing capacitor corresponding to the absolute ratio of the change in the equalizing coefficient to the change in the equalizing capacitor when the set equalizing criterion is first met is taken as the saturation point of the equalizing effect. The set equalizing criterion is shown in the following formula:

[0083] In the formula, The equalization sensitivity threshold, This represents the change in the equal pressure coefficient. This represents the change in the voltage equalization capacitance. The absolute ratio of the change in the equalizing voltage coefficient to the change in the equalizing voltage capacitor is given. In this embodiment, the absolute ratio is obtained by calculating the discrete difference based on the curve of the equalizing voltage coefficient changing with the equalizing voltage capacitor.

[0084] In this embodiment, the initial values ​​of the equalizing capacitors at both breaks are the same; ideally, the equalizing capacitor values ​​at both breaks are equal. The point corresponding to the first equalizing capacitor value that satisfies the set equalizing criterion is defined as the equalizing effect saturation point, indicating that further increasing the equalizing capacitor thereafter significantly reduces the improvement effect on equalizing voltage. The capacitor value corresponding to the equalizing effect saturation point is denoted as... Since the double-break vacuum circuit breaker already has the ability to effectively improve the voltage division at the break points when using this capacitance value, it is defined as the lower limit of the optimal configuration range of the equalizing capacitor under this environmentally friendly insulating medium.

[0085] Step 5.4: Calculate the ratio of the peak change of transient overvoltage borne by the high-potential end to the change of the voltage equalization capacitor. The voltage equalization capacitor that meets the set negative effect criterion is the point where the negative effect of transient overvoltage becomes prominent. The point where the negative effect of transient overvoltage becomes prominent is used as the upper limit of the optimal configuration range of the voltage equalization capacitor.

[0086] Based on the transient simulation model of the interruption, the transient overvoltage characteristics of multiple reignitions under different equalizing capacitors are extracted and analyzed to determine the point where the negative effect of transient overvoltage becomes prominent. In the preferred but non-limiting embodiment of the present invention, by gradually increasing the equalizing capacitor, the influence of the change in equalizing capacitor on the peak value of transient overvoltage, the rate of rise of instantaneous recovery voltage, and the intensity of high-frequency oscillation during the multiple reignition stage is analyzed in detail. The critical inflection point of transient overvoltage transitioning from decrease to increase is obtained, providing a basis for subsequently determining the configuration range of equalizing capacitor.

[0087] In the transient simulation model, the value of the equalizing capacitor is gradually increased according to a set step size, and small inductor current interruption simulations are performed sequentially. When the transient recovery voltage at the break point meets the reignition judgment condition, the model triggers the dielectric breakdown reignition logic, and the system enters a high-frequency oscillation stage containing stray capacitance and equalizing capacitor. During this stage, the break point voltage is affected not only by the voltage division effect of the capacitor but also by the energy redistribution at the moment of reignition. Therefore, it is necessary to perform statistical analysis on the peak value of the maximum transient overvoltage.

[0088] For each set of equalizing capacitor values, the voltage waveform of the load side during the multiple reignition overvoltages in this high-frequency oscillation phase is obtained through the model, and the maximum transient overvoltage peak value it withstands is recorded as . The high-potential break point typically withstands more severe transient voltages, therefore it is the primary focus of analysis. Statistical analysis is conducted for different voltage-equalizing capacitor values. Plot the curves of peak transient overvoltage with respect to equalizing capacitor during multiple reignitions. Analyze the influence trend of equalizing capacitor on transient overvoltage during multiple reignitions of the vacuum circuit breaker, and solve for the point where the negative effect of transient overvoltage becomes prominent.

[0089] Figure 3 To adopt / Analysis of the transient overvoltages during multiple reignitions in a mixed gas environment under different equalizing capacitances reveals that, in the initial stage of increasing the equalizing capacitance, a larger capacitance can slow down the rise rate of the transient voltage front, weakening the transient voltage surge under reignition conditions and playing a positive role in suppressing overvoltage. However, when the equalizing capacitance increases to a certain critical value, the energy stored in the capacitor is rapidly released into the arc channel at the moment of reignition, resulting in enhanced energy in the local LC high-frequency circuit, making the transient overvoltage waveform sharper and the peak value higher. The change in voltage equalization capacitance shows a U-shaped trend of first decreasing and then increasing, indicating that a larger voltage equalization capacitance is not necessarily more beneficial, but rather there is a reasonable upper limit.

[0090] The minimum value of the peak curve of transient overvoltage after multiple reignitions is solved, that is, the discrete rate of change of transient overvoltage with respect to equalizing capacitance is calculated.

[0091] The negative effect criterion is set as follows: ,

[0092] In the formula, This represents the maximum transient overvoltage peak value at the high-potential end of the break during multiple reignitions in the high-frequency oscillation phase, obtained through simulation under a set of equalizing capacitors. The equalizing capacitor that meets the negative effect criterion is defined as the point where the negative effect of transient overvoltage becomes prominent. This indicates that if the equalizing capacitor is continued to be increased thereafter, the overvoltage suppression effect will begin to decay and gradually turn into an adverse effect.

[0093] The capacitance value corresponding to the point where the negative effect of the multiple reignition transient overvoltage becomes prominent is denoted as Since this point is the physical critical point to prevent the energy backlash from repeated reignitions and to avoid the abnormal rise of transient overvoltage in the system, it is defined as the upper limit of the optimal configuration range of the voltage equalizing capacitor under this environmentally friendly insulating medium.

[0094] Step 6: Use the weighted sum of the lower and upper limits of the optimal configuration range of the voltage equalizing capacitor as the preferred value of the voltage equalizing capacitor, where the weights are adjusted based on the engineering design objectives; under transient performance constraints, the preferred value of the voltage equalizing capacitor is corrected to determine the configuration value of the voltage equalizing capacitor.

[0095] Specifically, step 6 includes: Step 6.1: Use the weighted sum of the lower and upper limits of the optimal configuration range of the voltage equalizing capacitor as the preferred value of the voltage equalizing capacitor, where the weights are adjusted based on the engineering design objectives.

[0096] Taking into account multiple factors, the optimal configuration range of equalizing capacitors for GIS double-break vacuum circuit breakers under different environmentally friendly insulation media was obtained. And according to the specific engineering design objectives, the voltage equalization capacitor configuration is completed within this range;

[0097] In the formula, The preferred value for the voltage equalization capacitor is... , All are weights. + =1; 1) When improving the pressure distribution at the fracture surface and controlling the size and cost of equipment are the engineering design goals, the optimization objectives are to minimize the deviation of the equalizing pressure coefficient from 1, minimize the equipment size, and minimize the equipment cost. > To select the nearest Data; 2) When suppressing transient overvoltages and improving breaking reliability are the engineering design goals, the optimization objectives are to minimize the transient overvoltage at the high-potential end of the circuit, minimize the transient overvoltage at the low-potential end of the circuit, and minimize the number of reignitions. < To select the nearest Data; 3) Improving voltage distribution at the break point, controlling equipment size and cost, suppressing transient overvoltages, and improving breaking reliability are all engineering design objectives. = .

[0098] Figure 4 For different proportions / The optimal configuration range for voltage equalization capacitors under mixed gas conditions satisfies both the voltage equalization effect and transient overvoltage suppression objectives, and therefore can serve as an effective range for selecting parallel voltage equalization capacitors under this environmentally friendly insulating medium condition.

[0099] Step 6.2: Under transient performance constraints, the preferred value of the voltage equalization capacitor is modified to determine the voltage equalization capacitor configuration.

[0100] The preferred value of the equalizing capacitor is substituted into the aforementioned transient simulation model for verification. The transient performance constraints include: 1) The peak transient recovery voltage of the double-break vacuum circuit breaker during multiple reignition processes does not exceed the national standard's allowable rated operating impulse withstand voltage: 2) The peak value of transient overvoltage of the load during multiple reignition processes does not exceed the national standard allowable rated operating impulse withstand voltage; 3) The equalization coefficient should not be higher than the set equalization threshold, which is usually taken as 1.1 in engineering.

[0101] If the verification results do not meet the requirements, fine-tuning is performed within the optimal configuration range until the optimal value of the voltage equalizing capacitor that meets the engineering requirements is obtained. Through the verification process, the optimal value of the voltage equalizing capacitor can be ensured to satisfy both the optimal configuration range of the voltage equalizing capacitor and the safety and reliability requirements of actual engineering operation.

[0102] Another aspect of this invention proposes a voltage equalization capacitor configuration system for a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, comprising: The simulation model building module is used to obtain the parameter range of the stray capacitance to ground of GIS using different environmentally friendly insulation media; and to build a transient simulation model of the breaking of a double-break vacuum circuit breaker, wherein the model includes the high-potential break on the power supply side, the low-potential break on the load side, and the stray capacitance to ground that meets the parameter range and is connected in parallel to the low-potential break. The uniform capacitor configuration module is used to simulate the transient process of a vacuum circuit breaker repeatedly interrupting small inductor currents under different stray capacitances to ground and different equalizing capacitors, based on the transient simulation model of interruption. When the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end detect that the break is in a reignition state, the equalizing capacitor that first meets the set equalizing criterion is used as the lower limit of the optimal configuration range of the equalizing capacitor, and the equalizing capacitor that meets the set negative effect criterion is used as the upper limit of the optimal configuration range of the equalizing capacitor, based on the peak value of the transient overvoltage borne by the high-potential end and the low-potential end. The weighted sum of the lower limit and the upper limit of the optimal configuration range of the equalizing capacitor is used as the preferred value of the equalizing capacitor. Under the transient performance constraints, the preferred value of the equalizing capacitor is corrected to determine the configuration value of the equalizing capacitor.

[0103] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0104] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0105] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0106] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0107] 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 protection scope of the claims of the present invention.

Claims

1. A method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, wherein the GIS uses an environmentally friendly insulating medium comprising multiple component gases; characterized in that, include: Obtain the parameter range of stray capacitance to ground for GIS using different environmentally friendly insulating media; A transient simulation model of a double-break vacuum circuit breaker is established. The model includes the high-potential break on the power supply side and its breaking logic control module, the low-potential break on the load side and its breaking logic control module, and the stray capacitance to ground connected in parallel to the low-potential break that satisfies the parameter range. Based on the transient simulation model of interruption, the transient process of a vacuum circuit breaker interrupting small inductor current multiple times under different stray capacitances to ground and different voltage equalization capacitors is simulated. When the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end detect that the break is in the reignition state, according to the peak value of the transient overvoltage borne by the high-potential end and the low-potential end, the voltage equalization capacitor that first meets the set voltage equalization criterion is taken as the lower limit of the optimal configuration range of the voltage equalization capacitor, and the voltage equalization capacitor that meets the set negative effect criterion is taken as the upper limit of the optimal configuration range of the voltage equalization capacitor. The weighted sum of the lower and upper limits of the optimal configuration range of the voltage equalizing capacitor is used as the preferred value of the voltage equalizing capacitor; under transient performance constraints, the preferred value of the voltage equalizing capacitor is modified to determine the configuration value of the voltage equalizing capacitor.

2. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage as described in claim 1, characterized in that, At a rated gas pressure of 0.7 MPa The scheme is used as the benchmark scheme, and the benchmark insulation strength is denoted as . , No. The insulation strength of environmentally friendly insulating media is Based on the principle of equivalent insulation, the insulation distance compensation amount for GIS using environmentally friendly insulating media is calculated. : In the formula, The equivalent insulation distance for the baseline scheme, For the first Equivalent insulation distance for environmentally friendly insulating media solutions; Based on the GIS insulation distance compensation, the stray capacitance to ground of GIS with different environmentally friendly insulation media is calculated using finite element simulation to obtain the stray capacitance parameter range. , and These represent the minimum and maximum values ​​of stray capacitance to ground under different environmentally friendly insulating media.

3. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage as described in claim 1, characterized in that, Establish a transient simulation model for the breaking of a double-break vacuum circuit breaker, including: An equivalent circuit for a double-break vacuum circuit breaker is established. The equivalent circuit includes a high-potential break and a low-potential break connected in series. The inter-electrode capacitance and equalizing capacitance of the high-potential break are connected in parallel with the high-potential break. The inter-electrode capacitance, equalizing capacitance, and stray capacitance to ground of the low-potential break are all connected in parallel with the low-potential break. The stray capacitance to ground meets the parameter range. The high-potential break and the low-potential break are equivalent to ideal switches. One end of the high-potential break is connected to the system power supply side, and the other end of the high-potential break is connected to one end of the low-potential break. The other end of the low-potential break is connected to the load side. Separate logic control modules are established for the high-potential break and the low-potential break. In the equivalent circuit, the high-potential break logic control module takes the current, power supply voltage, and load voltage of the high-potential break as input signals and the opening or closing of the high-potential break as output signals; the low-potential break logic control module takes the current, power supply voltage, and load voltage of the low-potential break as input signals and the opening or closing of the low-potential break as output signals. Both the high-potential and low-potential break logic control modules include: a current-cutting judgment unit, a reignition judgment unit, and a high-frequency arc-extinguishing judgment unit. The interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end are combined with the equivalent circuit topology to form the interruption transient simulation model of the dual-break vacuum circuit breaker.

4. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, as described in claim 3, is characterized in that... The current-cutting judgment unit is used to determine the transient recovery voltage of the high-potential and low-potential breaks in the equivalent circuit. , Inversely inferring the current before the circuit breaker is interrupted ,when hour Then it is determined that the flow has been blocked at the break point. The set interception threshold, For simulation time variables, This is the trigger time for the tripping command; The reignition detection unit is used to compare the transient recovery voltages of the high-potential and low-potential breaks in the equivalent circuit. , The transient pressure-bearing capacity of the medium at each fracture point is considered to be greater than the transient pressure-bearing capacity of the medium at the fracture point, and reignition is determined to have occurred. The high-frequency arc extinction judgment unit is used when the reignition judgment unit determines that reignition has occurred and the high-frequency oscillation stage after reignition has begun. If the high-frequency arc is extinguished, it is determined that the arc is extinguished; otherwise, the arc is not extinguished. The set threshold for high-frequency arc extinguishing capability; The real-time current at the break point, when =1 represents the real-time current at the high-potential break point. ,when =2 represents the real-time current at the low-potential break point. .

5. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, as described in claim 4, is characterized in that... During the transient process, if the simulation time does not exceed the set reignition determination period, the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end will cyclically execute the current cutting-off, reignition, and arc extinction status judgments of the break points, including: 1) If the current throttling judgment unit determines that current throttling has occurred, the opening logic control module of the high potential end break and the opening logic control module of the low potential end break will both send the opening control signal to the corresponding break. 2) The simulation ends when the simulation time exceeds the set re-ignition determination period. If the simulation time does not exceed the set re-ignition determination period but the re-ignition is not determined, the re-ignition status judgment is executed repeatedly until the simulation time exceeds the set re-ignition determination period. If the simulation time does not exceed the set re-ignition determination period and the re-ignition is determined, the opening logic control module of the high potential terminal and the opening logic control module of the low potential terminal both send a closing control signal to the corresponding terminal. 3) Execute the arc extinction judgment. If the arc is determined to be extinguished, the opening logic control module of the high potential end and the opening logic control module of the low potential end both send the opening control signal to the corresponding end and return to 2); if the arc is determined not to be extinguished, the arc extinction status judgment is executed cyclically.

6. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage as described in claim 1, characterized in that, In the transient simulation model of breaking, the initial value of the equalizing capacitor is set and the value is increased according to the set step size. The stray capacitance to ground under the same type of environmentally friendly insulating medium is repeatedly simulated. The transient overvoltage waveform of the double-break vacuum circuit breaker during the current cutting and multiple reignition processes is extracted, and the peak value of the transient overvoltage borne by the high potential end break and the low potential end break is recorded. Calculate the voltage averaging coefficient using the peak transient overvoltages borne by the two breaks. As shown in the following formula: In the formula, , These represent the peak transient overvoltages borne by the high-potential and low-potential break points, respectively.

7. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage as described in claim 6, characterized in that, The established equalization criterion is shown in the following formula: In the formula, The equalization sensitivity threshold, This represents the change in the equal pressure coefficient. This represents the change in the voltage equalization capacitance. It is the absolute ratio of the change in the equalizing coefficient to the change in the equalizing capacitance.

8. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, as described in claim 6, is characterized in that... The negative effect criterion is set as follows: ， In the formula, This represents the maximum transient overvoltage peak value at the high-potential end of the circuit during multiple reignitions in the high-frequency oscillation phase, obtained through simulation under a set of equalizing capacitors. This represents the change in the equalizing capacitance.

9. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage as described in claim 1, characterized in that, Optimal configuration range of equalizing capacitors for GIS double-break vacuum circuit breakers under different environmentally friendly insulating media , It is a voltage equalization capacitor. This represents the lower limit of the optimal configuration range for the voltage-equalizing capacitors. This represents the upper limit of the optimal configuration range for the voltage-equalizing capacitors. In the formula, The preferred value for the voltage equalization capacitor is... , All are weights. + =1.

10. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, as described in claim 9, is characterized in that... When the optimization objectives are to minimize the deviation of the equal pressure coefficient from 1, minimize the equipment volume, and minimize the equipment cost, > ; When the optimization objectives are to minimize the transient overvoltage at the high-potential end, the transient overvoltage at the low-potential end, and the number of reignitions, < ; When the optimization objectives are to minimize the deviation of the equalization coefficient from 1, minimize the equipment volume, minimize the equipment cost, minimize the transient overvoltage at the high potential end of the break, minimize the transient overvoltage at the low potential end of the break, and minimize the number of reignitions, = .

11. The method for configuring equalizing capacitors in a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, as described in claim 9, is characterized in that... Transient performance constraints include: 1) The peak transient recovery voltage of the double-break vacuum circuit breaker during multiple reignition processes does not exceed the national standard's allowable rated operating impulse withstand voltage: 2) The peak value of transient overvoltage of the load during multiple reignition processes does not exceed the national standard allowable rated operating impulse withstand voltage; 3) The equalization coefficient is not higher than the set equalization threshold.

12. A voltage-equalizing capacitor configuration system for a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage, used to implement the voltage-equalizing capacitor configuration method for a GIS double-break vacuum circuit breaker based on the characteristics of multiple reignition transient overvoltage as described in any one of claims 1 to 11, characterized in that, include: The simulation model building module is used to obtain the parameter range of stray capacitance to ground of GIS using different environmentally friendly insulating media; A transient simulation model of a double-break vacuum circuit breaker is established, which includes a high-potential break on the power supply side, a low-potential break on the load side, and a stray capacitance to ground connected in parallel to the low-potential break that satisfies the parameter range. The uniform capacitor configuration module is used to simulate the transient process of a vacuum circuit breaker repeatedly interrupting small inductor currents under different stray capacitances to ground and different equalizing capacitors, based on the interruption transient simulation model. When the interruption logic control module of the high-potential end and the interruption logic control module of the low-potential end detect that the break is in a reignition state, the equalizing capacitor that first meets the set equalizing criterion is used as the lower limit of the optimal configuration range of the equalizing capacitor, and the equalizing capacitor that meets the set negative effect criterion is used as the upper limit of the optimal configuration range of the equalizing capacitor. The weighted sum of the lower and upper limits of the optimal configuration range of the voltage equalizing capacitor is used as the preferred value of the voltage equalizing capacitor; under transient performance constraints, the preferred value of the voltage equalizing capacitor is modified to determine the configuration value of the voltage equalizing capacitor.

13. A terminal, comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1-11.

14. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method according to any one of claims 1-11.

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