Phase selection on-off control method and system of hydraulic mechanism circuit breaker

Abstract

The embodiment of the invention discloses a phase selection on-off control method and system for a hydraulic mechanism circuit breaker, and the method comprises the steps: S1, obtaining opening response characteristic parameters of the hydraulic mechanism circuit breaker under different working conditions, and forming a corresponding sample data set; s2, establishing a multi-physical-field coupling simulation model of the hydraulic mechanism circuit breaker, and obtaining corresponding mechanical action characteristic parameters under a target working condition in combination with the opening response characteristic parameters; s3, constructing a Mayr arc short circuit on-off simulation model, and obtaining arc characteristic parameters under different short circuit current conditions through the Mayr arc short circuit on-off simulation model so as to obtain corresponding shortest arcing time; and S4, according to the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism, determining a corresponding phase selection opening decision and executing opening operation. The method can adapt to the state change of the system, and the phase selection control accuracy, the adaptive capability and the engineering applicability of the circuit breaker in actual operation are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of intelligent control technology for high-voltage electrical equipment, specifically to the field of phase-selective interruption of short-circuit current in high-voltage circuit breakers with hydraulic mechanisms. More specifically, it relates to a phase-selective interruption control method and system for multi-field simulated coupled arc characteristics of circuit breakers equipped with hydraulic operating mechanisms. Background Technology

[0002] Circuit breakers are crucial switching devices in power systems, primarily used for switching normal equipment or lines, quickly disconnecting faulty equipment or lines, and providing safety isolation. Their breaking capacity directly impacts power system stability. In medium- and high-voltage projects, circuit breakers are typically required to complete breaking tasks quickly and reliably. Breaking near the current zero-crossing point significantly reduces arcing time and energy, greatly minimizing contact erosion and extending the circuit breaker's electrical life. Simultaneously, it significantly reduces the risk of excessively high operating overvoltages, protecting the disconnected equipment (such as motors, transformers, shunt reactors, and capacitor banks) and other system equipment from damage. This process involves not only high-speed separation of mechanical contacts but also intense arc discharge; therefore, the complexity and transient characteristics of this process must be comprehensively considered when developing high-voltage circuit breaker breaking control strategies.

[0003] Hydraulic operating mechanisms, due to their high output force, fast response speed, and compact structure, have been widely used in medium and high voltage circuit breakers in recent years. The performance of the hydraulic mechanism directly affects the mechanical stability of the circuit breaker. However, its response is affected by multiple factors, including the hydraulic system and transmission system, and is particularly significantly affected by fluctuations in ambient temperature and changes in oil pressure, exhibiting strong nonlinearity and variability. On the other hand, arcing is an unavoidable physical phenomenon during the circuit breaker's opening process. Its arc extinguishing behavior is not only related to the zero-crossing moment of the current but also closely related to the movement of the contacts. If the arc cannot be extinguished at an appropriate opening distance, it will lead to serious consequences such as reignition and breaking failure. In recent years, although arc theory models have been applied in research, they are still disconnected from the mechanism's operating process and fail to accurately predict the arc extinguishing timing by combining the mechanism's dynamic response process, making it difficult to support intelligent control decisions.

[0004] Currently, some circuit breakers use phase selection strategies for tripping operations to improve tripping efficiency and reduce system impact. These strategies mainly fall into categories such as those based on natural zero-crossing prediction, arc modeling, or reignition probability estimation. The core phase selection control strategies of these technologies largely rely on current waveforms or static characteristic values ​​as the basis for judgment. However, contact separation time and opening distance variation curves have a decisive impact on the arc formation and extinction process. If the mechanism's action characteristics under different operating conditions are not fully considered, and the actual coupling relationship between the mechanism response and the arc extinguishing physical process is ignored, the control accuracy and adaptability will be limited. Summary of the Invention

[0005] Based on this, in order to address the shortcomings of existing technologies, a phase selection and interruption control method for hydraulic circuit breakers is proposed.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A phase-selective interruption control method for a hydraulic circuit breaker includes:

[0008] S1: Obtain the tripping response characteristic parameters of the hydraulic circuit breaker under different operating conditions and form a corresponding sample dataset. The operating conditions include at least temperature, oil pressure and operating voltage.

[0009] S2: Establish a multi-physics field coupling simulation model of the hydraulic mechanism circuit breaker, and combine the tripping response characteristic parameters to obtain the corresponding mechanical action characteristic parameters under the target working condition through the multi-physics field coupling simulation model;

[0010] S3: Construct a Mayr arc short-circuit breaking simulation model, obtain arc characteristic parameters under different short-circuit current conditions through the Mayr arc short-circuit breaking simulation model, and then obtain the corresponding shortest arcing time;

[0011] S4: Based on the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism, determine the corresponding phase selection trip decision and execute the trip operation.

[0012] Optionally, in one embodiment, the mechanical action characteristic parameter includes the opening time t. o The formulas for contact stroke x and movement speed v are:

[0013] t o =f(P oil ,T,U operating )

[0014] x=ω(t0)

[0015]

[0016] Optionally, in one embodiment, the expression for the Mayr arc short-circuit breaking simulation model is:

[0017]

[0018] In the formula: g is the arc conductance, P is the arc dissipation power, τ is the arc time constant, and i is the short-circuit current.

[0019] Optionally, in one embodiment, the specific steps of S4 include:

[0020] S41. Based on the mechanical characteristic parameters of the hydraulic mechanism, establish a formula for calculating the time from the issuance of the tripping command to the contact moving to its full stroke, i.e., the control lead time t. s The calculation formula is t. s =t0+t o t0 is the moment of the initial division, t o This refers to the time for the circuit breaker to open.

[0021] S42. Establish a corresponding control criterion based on the control lead formula and the shortest arcing time. The corresponding control criterion formula is as follows:

[0022] t s =t o +t0≥t arc +Δt

[0023] Where Δt is the reserved arcing margin time;

[0024] S43. When a short-circuit fault is detected, the circuit breaker shall only operate if a certain phase of the circuit breaker meets the above control criterion conditions, and the corresponding shortest arcing time t is calculated in the shortest arcing time for each phase. arc If the shortest of the three phases is found, then that phase is deemed to have the optimal tripping condition, t0+t before the target zero-crossing point. o The tripping command is issued at all times, and the tripping control decision of the priority phase is executed.

[0025] In addition, a phase-selective interruption control system for a hydraulic circuit breaker is proposed, which includes:

[0026] The tripping response data acquisition unit is used to acquire the tripping response characteristic parameters of the hydraulic mechanism circuit breaker under different operating conditions and form a corresponding sample dataset. The operating conditions include at least temperature, oil pressure and operating voltage.

[0027] The multi-physics coupling simulation unit is used to establish a multi-physics coupling simulation model of the hydraulic mechanism circuit breaker, and in combination with the tripping response characteristic parameters, obtain the corresponding mechanical action characteristic parameters under the target working condition through the multi-physics coupling simulation model.

[0028] The short-circuit breaking simulation unit is used to construct the Mayr arc short-circuit breaking simulation model. Through the Mayr arc short-circuit breaking simulation model, the arc characteristic parameters under different short-circuit current conditions are obtained, and then the corresponding shortest arcing time is obtained.

[0029] The phase selection tripping decision setting unit is used to determine the corresponding phase selection tripping decision and execute the tripping operation based on the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism.

[0030] In addition, to address the shortcomings of traditional technologies in the face of challenges, a computer-readable storage medium is proposed, including computer instructions that, when executed on a computer, cause the computer to perform the method described.

[0031] Implementing the embodiments of the present invention will have the following beneficial effects:

[0032] The phase-selective tripping control method proposed in this invention establishes a coupled analysis method covering the entire tripping process by integrating multiphysics dynamic simulation of the hydraulic operating mechanism with arc characteristic modeling. This enables accurate prediction of the mechanism's action characteristics, contact separation moment, and arc duration under different operating conditions. Based on this, the phase-selective tripping control strategy comprehensively considers the mechanism's response and arc evolution process, dynamically assesses arc extinguishing capability, improves phase selection accuracy and tripping success rate, and reduces the risk of reignition. Therefore, compared with existing traditional phase-selective tripping strategies that rely on static electrical quantity judgments and ignore the coupling of mechanism behavior, this invention is more adaptable to system state changes and significantly improves the accuracy, adaptability, and engineering applicability of phase selection control in actual circuit breaker operation. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] in:

[0035] Figure 1 This is a flowchart of the circuit breaker phase selection and tripping control method described in this invention;

[0036] Figure 2 This is a schematic diagram of the topology of the hydraulic mechanism constructed according to the present invention;

[0037] Figure 3 This is a flowchart of the simulation steps of the multiphysics co-simulation model described in this invention;

[0038] Figure 4 These are simulation results of the hydraulic mechanism tripping simulation model built according to this invention, showing the stroke curves at different temperatures.

[0039] Figure 5 This is a simulation result diagram of the hydraulic mechanism tripping simulation model built by this invention, showing the stroke curves under different operating voltages;

[0040] Figure 6 This is a simulation result diagram of the hydraulic mechanism tripping simulation model built by this invention, showing the simulation results of different oil pressure stroke curves. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. It is understood that the terms “first,” “second,” etc., as used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element without departing from the scope of this application, and similarly, a second element may be referred to as a first element. Both the first element and the second element are elements, but they are not the same element.

[0043] Given that single-phase short circuits are the most common type of short-circuit fault in power systems, accounting for approximately 65-70% of all faults, this embodiment uses a single-phase short circuit as an example to introduce a phase-selective interruption control method based on multi-field simulation coupled arc characteristics of a hydraulic circuit breaker. Figure 1 As shown, it includes the following steps:

[0044] S1: Obtain the tripping response characteristic parameters of the hydraulic circuit breaker under different operating conditions and form a corresponding sample dataset. The operating conditions include at least temperature, oil pressure and operating voltage.

[0045] S2: Establish a multi-physics field coupling simulation model of the hydraulic mechanism circuit breaker, and combine the tripping response characteristic parameters to obtain the corresponding mechanical action characteristic parameters under the target working condition through the multi-physics field coupling simulation model;

[0046] S3: Construct a Mayr arc short-circuit breaking simulation model, obtain arc characteristic parameters under different short-circuit current conditions through the Mayr arc short-circuit breaking simulation model, and then obtain the corresponding shortest arcing time;

[0047] S4: Based on the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism, determine the corresponding phase selection trip decision and execute the trip operation.

[0048] In some specific embodiments, the establishment of the sample dataset in S1 can be achieved by building a circuit breaker mechanism tripping test platform to obtain tripping response characteristic parameters under different operating conditions (such as temperature, oil pressure, and operating voltage). Specifically, the tripping response characteristics include key parameters such as start-up time, initial tripping time, and contact displacement curve. The circuit breaker mechanism tripping test platform can be a conventional test bench consisting of a hydraulic operating mechanism body, a control signal triggering module, a displacement-time synchronous acquisition device, a pressure and temperature sensor group, and a high-speed data acquisition system for data acquisition. The test bench structure is not the focus of this invention and will not be elaborated here. After building the aforementioned circuit breaker mechanism tripping test platform, tripping tests are conducted on the circuit breaker prototype to obtain the hydraulic mechanism circuit breaker under different operating conditions (such as temperature, oil pressure, and operating voltage). The circuit breaker's tripping response characteristics under hydraulic pressure and operating voltage are analyzed, including key parameters such as the moment of tripping and the contact displacement curve. Preferably, different operating conditions are set during the tripping test: 1. Different hydraulic pressures, such as 47MPa, 50MPa, 53.5MPa, and 55MPa; 2. Different ambient temperatures, such as -5℃ and 40℃; and 3. Different operating voltage conditions, such as DC198V, DC220V, and DC242V). The circuit breaker is then triggered to perform the tripping action. In each test, the time interval from the issuance of the control command to the moment of contact tripping and the contact displacement-time curve, i.e., the moment of contact tripping, are recorded in real time. The moment of contact tripping data obtained from multiple tests is mapped to the corresponding hydraulic pressure, ambient temperature, and operating voltage parameters to form a sample dataset for correcting the subsequent simulation model.

[0049] In some specific embodiments, a multi-physics field coupling simulation model of the hydraulic mechanism circuit breaker is established in S2, and the mechanical action characteristic parameters corresponding to the target working condition are obtained through the multi-physics field coupling simulation model in combination with the tripping response characteristic parameters.

[0050] Specifically: The structural diagram of the hydraulic mechanism is attached. Figure 2 As shown in the figure (1. Disc spring, 2. Low-pressure cylinder, 3. High-pressure cylinder, 4. Oil tank, 5. Piston rod, 6. Electromagnetic control valve, 7. Hydraulic cylinder), the piston achieves directional movement under the action of the hydraulic pressure difference on both sides. Its opening process can be described by the following mechanical equilibrium equation:

[0051] ma=P1A1-P2A2-F

[0052] In the formula, m is the mass, a is the piston acceleration, P1 and P2 are the pressures of the rod-side and rodless sides of the hydraulic cylinder, respectively, A1 and A2 are the corresponding equivalent action areas, and F is the reaction force generated by the operating mechanism during the opening process.

[0053] Based on the structure and response characteristics of the hydraulic operating mechanism, as well as the mechanical balance equations in the piston motion process, a "multi-physics joint simulation model" can be established, that is, a joint simulation structure is constructed (involving the coupled modeling of multiple modules such as hydraulic system, mechanical transmission, contact feedback and control link).

[0054] The multi-physics coupling simulation model of the hydraulic circuit breaker involves physical fields including hydraulic fields and electromagnetic fields. This multi-physics coupling simulation model is used to simulate the change law of the moving contact displacement with time under the action of hydraulic fields and electromagnetic fields, so as to obtain the contact displacement-time relationship, contact velocity change curve and the time point t0 at the moment of opening under the target working condition. The model parameters of the multi-physics coupling simulation model are optimized and corrected by the above-mentioned measured data, namely the opening response characteristic parameters (using experimentally measured moving contact displacement with time data and hydraulic pressure data to correct the multi-physics coupling simulation model), thereby obtaining the mechanical action characteristic parameters corresponding to the target working condition.

[0055] The multi-physics joint simulation model set up in this invention establishes a simulation sub-model and realizes signal coupling and linkage, outputting key parameters such as contact displacement-time and velocity, which are used to predict the circuit breaker's opening behavior, that is, to simulate the dynamic response process of the mechanism from the issuance of control commands to the corresponding contacts, that is, how its mechanical action characteristics such as displacement, velocity, and acceleration are affected by hydraulic pressure, electromagnetic force, friction, inertia and other factors and how they evolve over time. In this way, the simulation model can be used to predict the mechanical action characteristics of the mechanism under different working conditions that are difficult to cover by experiments, that is, it can simulate the response behavior under different working conditions with high accuracy: the moment of opening and the contact stroke, i.e., contact displacement, movement velocity and other information.

[0056] Preferably, the multiphysics co-simulation model mainly includes a hydraulic power module, a pilot control module, a mechanical transmission module, and a contact motion feedback module. It simulates the dynamic response behavior of the mechanism from the issuance of control commands to the moment the contacts reach the point of contact separation (e.g., pilot control → hydraulic power → mechanical transmission → contact feedback). Specifically, the hydraulic power module simulates the energy conversion and transmission process of the hydraulic system; the pilot control module simulates the triggering and transmission mechanism of control commands; the mechanical transmission module simulates the energy conversion process from hydraulic thrust to mechanical motion; and the contact motion feedback module simulates the dynamic and breaking performance-related parameter characteristics of the arc-extinguishing chamber and obtains key data such as contact stroke, moment of contact separation, and contact separation speed.

[0057] The specific simulation process, such as Figure 3 ,include

[0058] Step S21: Issue a trip command, and through the pilot control module, simulate the response process from the solenoid valve coil current to the valve core displacement and send a valve opening signal;

[0059] Step S22: Receive the valve opening signal output by the pilot control module through the hydraulic power module, and calculate the main oil circuit flow rate and cylinder output force;

[0060] Step S23: Solve for the dynamic response parameters of the transmission mechanism based on the output data of the hydraulic power module using the mechanical transmission module;

[0061] Step S24: Receive the output data from the mechanical transmission module through the contact motion feedback module to obtain the motion trajectory of the moving contact, i.e., the change law of the moving contact displacement with time; at the same time, the reaction load output by the contact motion feedback module is fed back to the mechanical transmission module, and the inertial load output by the mechanical transmission module is fed back to the hydraulic power module.

[0062] Preferably, during the debugging of the multiphysics co-simulation model, the stiffness-break time and displacement change curves obtained from the above-mentioned experimental data are used as comparison and verification standards to repeatedly correct parameters such as the hydraulic cylinder damping coefficient, oil dynamic viscosity, and mechanical friction factor in the multiphysics co-simulation model. The goal of the correction is to minimize the error between the simulation output and the experimental measurement data, ensuring that the simulation output is highly consistent with the actual response, so that the corrected and verified model can reflect the dynamic characteristics of the actual mechanism with high fidelity. Finally, based on the optimized and adjusted multiphysics co-simulation model, the complete motion process of the circuit breaker tripping operation under different oil temperature (T) and oil pressure (P) conditions can be obtained, and the tripping time t can be extracted. o (Calculations begin immediately after separation), key physical quantities such as contact stroke x and velocity v, and their corresponding formulas are:

[0063] t o =f(P oil ,T,U operating )

[0064] x=ω(t0)

[0065]

[0066] The input parameters corresponding to the multiphysics co-simulation model include the initial oil pressure P. oil Ambient temperature T, operating voltage U operating The output parameters mainly include the contact displacement-time relationship, the contact speed change curve, and the time point t0 at the moment of separation.

[0067] In some specific embodiments, the arc characteristic parameters in S3 include obtaining arc resistance change parameters, arc voltage change parameters, and arcing time; that is, incorporating a Mayr arc and establishing a short-circuit breaking simulation model, and conducting simulations of different short-circuit currents, considering the differences in arcing time corresponding to different short-circuit currents, and obtaining electrical characteristic parameters such as arc resistance change and arcing time; the corresponding Mayr arc short-circuit breaking simulation model expression is:

[0068]

[0069] In the formula: g is the arc conductance, P is the arc dissipation power, τ is the arc time constant, and i is the short-circuit current; and P and τ are obtained directly through experiments.

[0070] Since the arc conductance derivative dg / dt0 is the essential physical quantity characterizing the dynamic evolution of the arc, key parameters such as arc resistance change parameters, arc voltage change parameters, and arcing time can be obtained by analyzing this derivative, thereby providing data support for the precise decision-making of subsequent phase selection control; that is, the dynamic characteristics of the arc model (especially the rate of change of arc conductance) are used as the constraint condition for successful arc extinguishing, and the minimum value that satisfies the arc extinguishing condition is found by adjusting the assumed arcing time, that is, the shortest arcing time under each short-circuit current (the reason why it can be used as a constraint condition is that under the same short-circuit current, the different moments of the circuit breaker's breaking determines the arcing time of this breaking, and the arcing time = the moment of the target natural zero crossing - the moment of breaking. Therefore, the arc model is used to determine whether the circuit breaker can successfully extinguish the arc at the target natural zero crossing under different arcing times, that is, whether the arc will not reignite after the zero crossing).

[0071] Finally, based on this short-circuit breaking simulation model, the arcing situation of the circuit breaker under different short-circuit currents was obtained, and the corresponding shortest arcing time t was extracted. arc If the above conditions are used as constraints, the short-circuit breaking simulation model is used to gradually determine the minimum arcing time that can guarantee successful arc extinguishing at the zero-crossing point of the target current under different short-circuit current amplitudes, target current zero-crossing times, and circuit breaker characteristics (such as nozzle size, air pressure, etc.). Then, the corresponding iterative algorithm is used to gradually approximate the minimum arcing time that can guarantee successful arc extinguishing at the zero-crossing point of the target current under the same short-circuit current amplitude, thereby obtaining the shortest arcing time corresponding to different short-circuit currents.

[0072] In some specific embodiments, S4 can prioritize the phase with more favorable arc-extinguishing conditions to issue the tripping command based on different operating conditions and short-circuit conditions, and simultaneously correct the control logic of other phases to realize a high-precision multi-factor coupled phase selection and tripping control strategy based on "fault condition-environmental condition-control strategy"; that is, based on the obtained mechanical and electrical characteristic parameters of the hydraulic mechanism, the phase with more favorable arc-extinguishing conditions is prioritized for tripping operation, and under the premise of meeting the shortest arc-ignition time, the mechanism's start-up time is given by comprehensively considering environmental factors, and a phase selection tripping strategy is proposed.

[0073] Based on the above design concept, the specific steps of S4 include:

[0074] S41. Based on the mechanical characteristic parameters of the hydraulic mechanism, establish a formula for calculating the time from the issuance of the tripping command to the contact moving to its full stroke, i.e., the control lead time t. s The calculation formula is t. s =t0+t o t0 is the moment of the initial division, t o This refers to the time for the circuit breaker to open.

[0075] S42. Establish a corresponding control criterion based on the control lead formula and the shortest arcing time. The corresponding control criterion formula is as follows:

[0076] t s =t o +t0≥t arc +Δt

[0077] Wherein, Δt is the reserved arcing margin time, which takes a value of 4.5ms to 5ms.

[0078] The design principle of this step is as follows: In the control step of this step, in order to ensure that the circuit breaker reliably extinguishes the arc near the current zero crossing point, this invention proposes to use the shortest arcing time as the key control criterion (different short-circuit fault locations, different short-circuit grounding resistances, and different short-circuit times under single-phase short-circuit conditions will cause different short-circuit current conditions (short-circuit time, rise rate, initial value of short-circuit current, etc., therefore, it is necessary to specifically analyze the different shortest arcing times corresponding to different short-circuit current conditions, and provide technical requirements for the timing of hydraulic mechanism action commands and mechanical characteristics); the shortest arcing time is obtained by Mayr arc model simulation to reflect the shortest time required for arc maintenance under different short-circuit currents; if the system does not form a sufficient opening distance during this period, it may cause arc reignition, leading to interruption failure.

[0079] Therefore, based on the mechanism response characteristics obtained in step S2 (such as the moment the contacts just separate and the change in stroke), it is necessary to determine how much time in advance the tripping command should be issued to ensure that the duration from the moment of contact separation to the current zero-crossing point is greater than the sum of the shortest arcing time and the reserved margin. Based on the above analysis, it can be seen that this constraint constitutes the core basis for the phase separation decision.

[0080] S43. When a short-circuit fault is detected, the circuit breaker shall only operate if a certain phase of the circuit breaker meets the above control criterion conditions, and the corresponding shortest arcing time t is calculated in the shortest arcing time for each phase. arc If the shortest of the three phases is found, then that phase is deemed to have the optimal tripping condition, t0+t before the target zero-crossing point. o A tripping command is issued at all times, and the priority tripping control decision for that phase is executed. Specifically, the shortest arcing time for each phase of the circuit breaker is obtained independently based on the short-circuit breaking simulation model. It is determined which phase in each phase satisfies the S42 formula, and the phase with the minimum shortest arcing time (e.g., phase B) is identified. Only for the selected optimal phase (phase B), a tripping command is issued to the hydraulic mechanism of phase B. This step ensures that phase B, requiring the shortest arcing time (a smaller value means a shorter arcing time is needed for reliable arc extinguishing) and having the lowest requirement for tripping timing accuracy, is determined as the optimal priority tripping phase. This effectively improves the overall breaking success rate of the hydraulic circuit breaker under dispersed mechanism response. A smaller arcing time means the latest allowed tripping time is later than other phases, and even with a slight delay in mechanism action, it may still be satisfied. Conversely, a larger arcing time means the phase needs an earlier tripping time; if the mechanism response is delayed, the actual arcing time may be insufficient, leading to breaking failure.

[0081] Based on the same inventive concept, this invention also proposes a phase-selective interruption control system for a hydraulic circuit breaker, comprising:

[0082] The tripping response data acquisition unit is used to acquire the tripping response characteristic parameters of the hydraulic mechanism circuit breaker under different operating conditions and form a corresponding sample dataset. The operating conditions include at least temperature, oil pressure and operating voltage.

[0083] The multi-physics coupling simulation unit is used to establish a multi-physics coupling simulation model of the hydraulic mechanism circuit breaker, and in combination with the tripping response characteristic parameters, obtain the corresponding mechanical action characteristic parameters under the target working condition through the multi-physics coupling simulation model.

[0084] The short-circuit breaking simulation unit is used to construct the Mayr arc short-circuit breaking simulation model. Through the Mayr arc short-circuit breaking simulation model, the arc characteristic parameters under different short-circuit current conditions are obtained, and then the corresponding shortest arcing time is obtained.

[0085] The phase selection tripping decision setting unit is used to determine the corresponding phase selection tripping decision and execute the tripping operation based on the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism.

[0086] Based on the same inventive concept, the present invention also proposes a computer-readable storage medium including computer instructions that, when executed on a computer, cause the computer to perform the method described thereon.

[0087] Simultaneously combined Figures 4-6 The simulation results reveal the influence of three key operating parameters—temperature, operating voltage, and oil pressure—on the mechanical response characteristics of the circuit breaker. By analyzing the contact travel-time relationship and the trend of change at the moment of contact breakage output by the model, the control lead time ts can be effectively derived, and a precise phase selection breaking criterion can be constructed accordingly, thereby achieving dynamic phase selection control adaptable to different operating conditions. This simulation verification further demonstrates that the method of this invention possesses high adaptability and control accuracy under complex operating conditions, exhibiting a significantly superior technical effect compared to traditional static criterion strategies.

[0088] Implementing the embodiments of the present invention will have the following beneficial effects:

[0089] This invention considers ambient temperature and oil pressure conditions, and can provide different stroke curves by adjusting the operating voltage to meet the need for shortening the arcing time. It also takes into account the differences in arcing time corresponding to different short-circuit faults, demonstrating a comprehensive overall strategy. It achieves high-precision phase selection and interruption control based on the coupled logic of "fault condition-environmental conditions-control strategy," and simultaneously corrects the control delay time of other phases.

[0090] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A phase-selective interruption control method for a hydraulic circuit breaker, characterized in that, include: S1: Obtain the tripping response characteristic parameters of the hydraulic circuit breaker under different operating conditions and form a corresponding sample dataset. The operating conditions include at least temperature, oil pressure and operating voltage. S2: Establish a multi-physics field coupling simulation model of the hydraulic mechanism circuit breaker, and combine the tripping response characteristic parameters to obtain the corresponding mechanical action characteristic parameters under the target working condition through the multi-physics field coupling simulation model; S3: Construct a Mayr arc short-circuit breaking simulation model, obtain arc characteristic parameters under different short-circuit current conditions through the Mayr arc short-circuit breaking simulation model, and then obtain the corresponding shortest arcing time; S4: Based on the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism, determine the corresponding phase selection trip decision and execute the trip operation.

2. The phase selection and interruption control method for a hydraulic circuit breaker according to claim 1, characterized in that, The mechanical action characteristic parameters include the opening time t. o The formulas for contact stroke x and movement speed v are: t o =f(P oil ,T,U operating ) x=ω(t0) 3. The phase selection and interruption control method for a hydraulic circuit breaker according to claim 1, characterized in that, The Mayr arc short-circuit interruption simulation model expression is as follows: In the formula: g is the arc conductance, P is the arc dissipation power, τ is the arc time constant, and i is the short-circuit current.

4. The phase selection and interruption control method for a hydraulic circuit breaker according to claim 1, characterized in that, The specific steps of S4 include: S41. Based on the mechanical characteristic parameters of the hydraulic mechanism, establish a formula for calculating the time from the issuance of the tripping command to the contact moving to its full stroke, i.e., the control lead time t. s The calculation formula is t. s =t0+t o t0 is the moment of the initial division, t o This refers to the time for the circuit breaker to open. S42. Establish a corresponding control criterion based on the control lead formula and the shortest arcing time. The corresponding control criterion formula is as follows: t s =t o +t0≥t arc +Δt Where Δt is the reserved arcing margin time; S43. When a short-circuit fault is detected, the circuit breaker shall only operate if a certain phase of the circuit breaker meets the above control criterion conditions, and the corresponding shortest arcing time t is calculated in the shortest arcing time for each phase. arc If the shortest of the three phases is found, then that phase is deemed to have the optimal tripping condition, t0+t before the target zero-crossing point. o The tripping command is issued at all times, and the tripping control decision of the priority phase is executed.

5. A phase selection and breaking control system for a hydraulic circuit breaker, characterized in that, include: The tripping response data acquisition unit is used to acquire the tripping response characteristic parameters of the hydraulic mechanism circuit breaker under different operating conditions and form a corresponding sample dataset. The operating conditions include at least temperature, oil pressure and operating voltage. The multi-physics coupling simulation unit is used to establish a multi-physics coupling simulation model of the hydraulic mechanism circuit breaker, and in combination with the tripping response characteristic parameters, obtain the corresponding mechanical action characteristic parameters under the target working condition through the multi-physics coupling simulation model. The short-circuit breaking simulation unit is used to construct the Mayr arc short-circuit breaking simulation model. Through the Mayr arc short-circuit breaking simulation model, the arc characteristic parameters under different short-circuit current conditions are obtained, and then the corresponding shortest arcing time is obtained. The phase selection tripping decision setting unit is used to determine the corresponding phase selection tripping decision and execute the tripping operation based on the obtained mechanical action characteristic parameters and arc characteristic parameters of the hydraulic mechanism.

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