Spring state evaluation method in a spring circuit breaker based on a binary hysteresis

Abstract

This invention discloses a method for evaluating the spring state in a spring circuit breaker based on a binary loop, comprising the following steps: S1: Within one operating cycle of the spring circuit breaker, the start-up time of the actuator is recorded sequentially. t 1. Time of termination of the executing agency t 3 and the end of spring energy storage t 2 S2: In t 1~ t 2 Within a given time period, the pressure values ​​at the end of the spring were collected at different times and recorded as follows: F s ( t The linear velocity of the actuator crank arm end is collected at different times, and the displacement of the spring end relative to its natural state is approximately calculated based on this linear velocity, denoted as . x ( t S3: with x ( t () is the x-axis. F s ( t S4: Calculate key parameters based on the binary loop. S5: Develop evaluation rules to assess the spring condition. This invention introduces the concept of a binary loop for the first time in the condition assessment of spring circuit breakers. By analyzing the loop, various health indicators are obtained, avoiding the uncertainties brought about by black-box algorithms and purely empirical criteria.

Description

Technical Field

[0001] This invention relates to the field of spring circuit breaker condition assessment technology, and in particular to a spring circuit breaker condition assessment method based on a binary loop. Background Technology

[0002] Spring circuit breakers are one of the most widely used types of high-voltage switchgear in power systems. They utilize an energy-storing spring as a drive source, relying on the energy stored in a motor and the operation of the closing and opening coils to achieve the breaking operation. Compared to hydraulic or pneumatic mechanisms, spring circuit breakers are more compact, reliable, and easier to maintain, thus finding widespread application in power transmission and distribution systems, distribution networks, and large industrial users. The ability of the spring mechanism to provide sufficient closing and opening energy directly affects the speed and reliability of the circuit breaker contacts, thereby influencing the grid's ability to safely disconnect fault currents during short-circuit faults. If the spring performance deteriorates, its stiffness decreases, or its preload weakens, it will lead to insufficient contact speed, incomplete opening and closing, and reclosing failures. In severe cases, it can cause the circuit breaker to fail to operate or malfunction, resulting in widespread power outages or equipment damage, with extremely serious consequences.

[0003] As operating time increases, the main springs of spring circuit breakers exhibit aging phenomena such as metal fatigue, plastic creep, surface wear, and lubrication failure. These changes not only reduce the spring's output energy but also increase internal friction and energy loss, thereby accelerating the overall performance degradation of the circuit breaker. Therefore, effectively assessing the condition of circuit breaker springs is an important research direction for ensuring the safe operation of the power grid.

[0004] The performance testing of a single spring is generally carried out by monitoring the static pressure and extension of the spring with sensors to solve for the elastic modulus. The fatigue loss of the spring is judged based on the value of the elastic modulus. However, this testing method does not take into account the actual application scenario of the spring. For example, in a circuit breaker, the working state of the spring is a cyclical motion process from the spring extending to start the mechanism to the spring retracting until the energy storage ends. Therefore, it is necessary to evaluate whether the performance of the spring can support this continuous motion process.

[0005] Currently, common spring condition assessment methods in the circuit breaker field mainly include the following categories: (1) Mechanical measurement method, which directly collects the kinematic parameters of the mechanism through displacement sensors, velocity sensors, etc., and then calculates the spring condition by combining finite element or energy balance models. However, this type of method has complex sensor layout and the signal is easily affected by electromagnetic interference, making it difficult to operate stably on-site for a long time; (2) Current characteristic method, which uses the current of the energy storage motor and the current curve of the closing coil or opening coil as an indirect characterization of the spring performance. This method has simple hardware, but the current waveform is affected by factors such as power supply voltage, coil parameters, and temperature, making it difficult to accurately separate the characteristics of spring aging; (3) Offline test method, which detects the overall performance of the mechanism through power frequency withstand voltage, dynamic characteristic test, etc., and then indirectly judges the spring condition. However, this type of method requires power outage, and the cycle is long and the cost is high, making it unsuitable for online condition assessment. In summary, existing methods either involve too many measurements and rely on complex sensors, or rely on current signals and lack physical mechanism support, making it difficult to balance accuracy, interpretability, and engineering feasibility. Summary of the Invention

[0006] To address the technical problems of existing spring state assessment methods, such as excessive measurement, reliance on complex sensors, or lack of physical mechanism support, which make it difficult to balance accuracy, interpretability, and engineering feasibility, this invention provides a spring state assessment method for spring circuit breakers based on a binary loop to solve the above problems.

[0007] The technical solution adopted by this invention to solve its technical problem is: a method for evaluating the spring state in a spring circuit breaker based on a binary loop, comprising the following steps: S1: Within one operating cycle of the spring circuit breaker, record the start time of the actuator sequentially. t 1. Time of termination of the executing agency t 3 and the end of spring energy storage t 2 .

[0008] S2: In t 1~ t 2 Within a given time period, a pressure sensor is used to collect the pressure value at the end of the spring in real time, which is recorded as follows: F s ( t A linear velocity sensor is used to collect the linear velocity at the end of the crank arm of the actuator in real time. And based on this linear velocity, the displacement of the spring end relative to its natural state is approximately calculated, denoted as . x ( t ).

[0009] S3: with x ( t () is the x-axis,F s ( t Establish a two-dimensional coordinate system with the vertical axis as the coordinate, based on the point set collected in step S2 { x ( t ), F s ( t Draw a binary hysteresis loop.

[0010] S4: Calculate the key parameters based on the binary loop.

[0011] S5: Develop evaluation rules based on the key parameters and assess the spring state.

[0012] In an optional embodiment of the present invention, in step S1, the actuator start time t 1、 When the executing agency stops t 3 and the end of spring energy storage t 2 The definition method is as follows: S11: Select a minimum speed value and define it as the linear velocity threshold at the end of the actuator crank arm. .

[0013] S12: The linear velocity at the end of the actuator crank arm exceeds the linear velocity threshold. The time is t 1. With t After 1 moment, the linear velocity at the end of the actuator crank arm is first less than the linear velocity threshold. And last for a specified time t The time after 0 is t 3, with t After 3 seconds, the linear velocity at the end of the actuator crank arm is again less than the linear velocity threshold. And last for a specified time t The time after 0 is t 2.

[0014] In an optional embodiment of the present invention, the linear velocity threshold The value range is 0.02~0.03 m / s; the specified time t The value of 0 ranges from 50 to 60 ms.

[0015] In an optional embodiment of the present invention, in step S2, the spring end displacement x ( t The calculation method for ) is as follows: S21: Calculate the conversion coefficient between the movement distance of the actuator crank arm and the displacement of the spring end. .

[0016] S22: Using the aforementioned conversion coefficient The displacement at the end of the spring is approximated using a first-order model. x ( t ) and the linear velocity at the end of the actuator crank arm The relationship is used to calculate the displacement of the spring end at different times. x ( t ).

[0017] In an optional embodiment of the present invention, the conversion coefficient In the formula, x For any tiny time range t 01 ~ t 02 The deformation of the inner spring, where, t 01 and t 02 These represent the start and end times within any infinitesimal time interval, respectively.

[0018] In an optional embodiment of the present invention, the first-order model in step S22 is: In the formula, x 0 represents the initial displacement of the spring end, and τ represents the time integral variable.

[0019] In an optional embodiment of the present invention, in step S4, the key parameter includes instantaneous stiffness. k Mid-section pre-tightening deformation Hysteresis energy loss And the energy available to the spring ,in, ; ; ; ; In the formula, Mid-section stiffness is the spring deformation. x ( t () is the maximum value The instantaneous stiffness at half its value; When the spring deformation x ( t () is the maximum value The static pressure of the spring at half its capacity, dF s dx represents the infinitesimal pressure at the end of the spring, and dx represents the infinitesimal displacement of the end of the spring relative to its natural state. F s(t+1) represents the pressure value at the end of the spring at time t+1, F s (t) represents the pressure value at the end of the spring at time t, x(t+1) represents the displacement of the end of the spring relative to its natural state at time t+1, and x(t) represents the displacement of the end of the spring relative to its natural state at time t. i This represents the i-th x-coordinate after dividing the hysteresis loop into a series of infinitesimal curve segments along the x-axis; i+1 x represents i The next x-coordinate; F s,i x represents i The ordinate value of the hysteresis loop corresponding to the position; F s,i+1 x represents i+1 The vertical coordinate value of the hysteresis loop corresponding to the position, x(t1) represents the x-coordinate at the moment the actuator starts. The x-coordinate represents the moment when the actuator stops.

[0020] In an optional embodiment of the present invention, step S4 further includes calculating the main health index of the spring: stiffness retention rate. Preload drift rate Hysteresis Increment Rate Energy deficit rate ,in, ; ; ; ; In the formula, , , , These represent the spring's interrupted stiffness at the time of manufacture, the amount of preload deformation in the middle section, the hysteresis energy loss, and the spring's usable energy, respectively.

[0021] In an optional embodiment of the present invention, the evaluation rules in step S5 include the following steps: S51: If at least one health indicator is above 30%, the output status is poor; if each health indicator is below 30%, proceed to step S52.

[0022] S52: Calculate the average of all major health indicators. .

[0023] S53: Calculating Collaborative Rewards ,in .

[0024] S54: Calculate Imbalance Penalty .

[0025] S55: Calculate the coupling results .

[0026] S56: According to Sum The numerical output evaluation results.

[0027] In an optional embodiment of the present invention, the output criterion for the evaluation result is: if If the output state is excellent, then the output state is good; if If the output status is good, then the output status is good; if If the output state is 0, the output state is 0; otherwise, the output state is 0.

[0028] The beneficial effects of this invention are: (1) This invention introduces the concept of a binary loop in the condition assessment of spring circuit breakers for the first time, namely, constructing a spring force-displacement loop. Through the analysis of the loop, a series of physically interpretable indicators such as spring stiffness retention rate, preload drift, hysteresis energy loss, and available energy decay are obtained. Compared with existing diagnostic methods that rely solely on current characteristics or single kinematic parameters, this invention can comprehensively characterize the spring degradation process based on energy conservation and mechanical mechanisms, avoiding the uncertainties brought about by black-box algorithms and purely empirical criteria.

[0029] (2) This invention relies on only two types of signals, namely the static pressure at the end of the spring and the linear velocity at the end of the crank arm of the actuator, without the need for additional complex sensors. This design not only greatly reduces the measurement complexity, but also improves the robustness and versatility of the diagnosis, and truly realizes high-precision online status assessment with minimal measurement.

[0030] (3) The evaluation rules proposed in this invention model the four main health indicators simultaneously in three dimensions: average level, synergistic improvement, and imbalance suppression. They are both interpretable and engineering operable, avoiding complex training dependencies and are suitable for rapid deployment and on-site verification of online status assessment of spring circuit breakers.

[0031] (4) This invention calculates the conversion coefficient between the movement distance of the actuator crank arm and the displacement of the spring end within a small time range, thereby approximating the displacement of the spring end through a first-order model. x ( t ) and the linear velocity at the end of the actuator crank arm Relationship, Attached Figure Description

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0033] Figure 1 This is a flowchart of the spring state evaluation method in a spring circuit breaker based on a binary loop, as described in this invention. Figure 2 It is a binary hysteresis loop plot drawn using the method described in this invention; Figure 3 This is a flowchart of the evaluation rules in step S5. Detailed Implementation

[0034] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0035] like Figures 1-3 As shown, a method for evaluating the spring state in a spring circuit breaker based on a two-way loop includes the following steps: S1: Within one operating cycle of the spring circuit breaker, record the start time of the actuator sequentially. t 1. Time of termination of the executing agency t 3 and the end of spring energy storage t 2 .

[0036] A spring circuit breaker includes a closing spring and a opening spring. This invention analyzes the opening spring as an example. During one operating cycle of the spring circuit breaker, the working process of the opening spring is as follows: In the initial stage, the circuit breaker is closed, and the opening spring is in a contracted, energy-storing state; when a line fault occurs and the circuit breaker prepares to open, the opening spring pushes the actuator to start, and this starting moment is denoted as... t 1; When the actuator stops, the circuit breaker completes its opening. At this moment, the end displacement of the trip spring is at its maximum. Record this moment as . t 3; After the fault is cleared, the actuator closes the circuit breaker under the action of the closing spring. During this process, the opening spring begins to store energy until the circuit breaker is fully closed. At this point, the energy storage of the opening spring ends, and this moment is recorded as _____. t 2 .

[0037] S2: In t 1~ t 2 Within a given time period, a pressure sensor is used to collect the pressure value at the end of the spring in real time, which is recorded as follows: F s ( t A linear velocity sensor is used to collect the linear velocity at the end of the crank arm of the actuator in real time. And based on this linear velocity, the displacement of the spring end relative to its natural state is approximately calculated, denoted as . x ( t ).

[0038] The pressure sensor is installed at the end of the spring, and the linear velocity sensor is installed at the end of the crank arm of the actuator. To ensure measurement accuracy, the pressure sensor preferably has the following parameters: a range of 0 to 20 kN, a measurement accuracy of not less than ±1%FS, and a sampling frequency of not less than 2 kHz. The linear velocity sensor preferably has the following parameters: a measurement range of 0 to 2 m / s, a measurement accuracy of not less than ±0.5%FS, and a sampling frequency of not less than 2 kHz.

[0039] Key moments can be selected based on data collected by the linear velocity sensor. t 1. t 2 and t 3 The specific value is selected as follows: First, select one operating cycle of the spring circuit breaker based on the data collected by the linear velocity sensor (since the linear velocity change pattern at the end of the actuator crank arm is the same in different operating cycles of the circuit breaker, one operating cycle of the spring circuit breaker can be selected from the data collected by the linear velocity sensor within different consecutive periods). Then, within the selected operating cycle, the linear velocity at the end of the actuator crank arm exceeds the linear velocity threshold. The time is t 1. With t After 1 moment, the linear velocity at the end of the actuator crank arm is first less than the linear velocity threshold. And last for a specified time t The time after 0 is t 3, with t After 3 seconds, the linear velocity at the end of the actuator crank arm is again less than the linear velocity threshold. And last for a specified time t The time after 0 is t 2. Among them, the linear velocity threshold This is the minimum limit for the linear velocity at the end of the actuator's crank arm. When the actuator starts, the linear velocity at the end of the actuator's crank arm begins to exceed the linear velocity threshold. Linear velocity threshold The value range is 0.02~0.03 m / s. When the actuator is about to fully open or fully close, the linear velocity change at the end of the crank arm is small. When the crank arm of the actuator exhibits stable low-speed movement, the surface indicates that it is about to fully open or fully close. The duration is... t The setting of 0 is to prevent structural jamming from causing a momentary decrease in the speed of the actuator arm during operation, which could lead to errors in motion state judgment. The specified time... t The value of 0 ranges from 50 to 60 ms.

[0040] The spring end displacement x ( t The calculation method for ) is as follows: S21: Calculate the conversion coefficient between the movement distance of the actuator crank arm and the displacement of the spring end. Since the displacement of the actuator crank arm is usually not directly equal to the spring deformation, a conversion coefficient needs to be defined. This conversion coefficient is calculated and used as a constant in the first-order model in step S22.

[0041] The conversion coefficient is calculated by measuring the spring within any small time range t during maintenance or low-speed jogging mode. 01 ~t 02 Miniature journeys within (Measure the change in spring compression using calipers / displacement gauges), and read t from the speed sensor. 01 ~t 02 linear velocity over time range When the stroke is small, the displacement of the actuator crank arm is approximately equal to the deformation of the spring, therefore .in, t 01 and t 02 These represent the start and end times within any infinitesimal time interval, respectively.

[0042] S22: Using the aforementioned conversion coefficient The displacement at the end of the spring is approximated using a first-order model. x ( t ) and the linear velocity at the end of the actuator crank arm The relationship is used to calculate the displacement of the spring end at different times. x ( t ).

[0043] Let the angle of the crank arm be... θ ( t The radius from the end of the crank arm to the center of rotation is... r Then the linear velocity at the end of the crank arm With angular velocity The relationship is: , .

[0044] Spring deformation x ( t ) is a with θ ( t The related functions indicate that the spring deformation increases with the increase of the crank arm angle. In online identification scenarios, this relationship can be approximated by a first-order model: , in, That is, the conversion factor. Therefore: In the formula, x 0 represents the initial displacement of the spring end relative to its natural state, and τ represents the time integral variable.

[0045] This invention indirectly calculates the displacement value of the spring end by measuring the linear velocity of the actuator crank arm, rather than directly measuring the displacement value of the spring end by a displacement sensor. The reason for this is that the components of a displacement sensor are relatively complex. The spring is located in a closed space inside the circuit breaker, while the actuator crank arm is located outside the circuit breaker. Due to limitations such as space size, insulation requirements, and equipment reliability, it is more convenient to install a linear velocity sensor at the end of the crank arm, and it does not require changing the original internal structure of the circuit breaker.

[0046] S3: with x ( t () is the x-axis, F s ( t Establish a two-dimensional coordinate system with the vertical axis as the coordinate. x ( t The displacement of the spring's end relative to its natural state is given by the coordinate system. Therefore, a two-dimensional coordinate system is established with the origin at the spring's end displacement and pressure value in its natural state. The displacement in the spring's extension direction is represented by the positive x-axis, and the displacement in the spring's retraction direction by the negative x-axis. Points are marked in the coordinate system using the values ​​obtained in step S2, and then connected in chronological order to form a graph. Figure 2 The binary hysteresis loop shown.

[0047] S4: Calculate key parameters based on the binary loop, and conduct a comprehensive evaluation by simultaneously monitoring several parameters of the reaction spring state to ensure the accuracy of the evaluation results.

[0048] The key parameters include instantaneous stiffness. k Mid-section pre-tightening deformation Hysteresis energy loss And the energy available to the spring ,in, ; ; ; ; In the formula, Mid-section stiffness is the spring deformation. x ( t () is the maximum value The instantaneous stiffness at half its value; When the spring deformation x ( t () is the maximum value The static pressure of the spring at half its capacity, dF s dx represents the infinitesimal pressure at the end of the spring, and dx represents the infinitesimal displacement of the end of the spring relative to its natural state. F s (t+1) represents the pressure value at the end of the spring at time t+1, F s (t) represents the pressure value at the end of the spring at time t, x(t+1) represents the displacement of the end of the spring relative to its natural state at time t+1, and x(t) represents the displacement of the end of the spring relative to its natural state at time t. i This represents the i-th x-coordinate after dividing the hysteresis loop into a series of infinitesimal curve segments along the x-axis; i+1 x represents i The next x-coordinate; F s,i x represents i The ordinate value of the hysteresis loop corresponding to the position; F s,i+1 x represents i+1 The vertical coordinate value of the hysteresis loop corresponding to the position, x(t1) represents the x-coordinate at the moment the actuator starts. The x-coordinate represents the moment when the actuator stops. This involves transforming the integral of the hysteresis loop into the calculation of the area of ​​a series of curvilinear trapezoids and then summing them.

[0049] Instantaneous stiffness k This indicates the local stiffness of a spring at a specific deformation location; essentially, it is the rate of change of force per unit deformation. This indicator primarily measures whether the elastic properties of a material have deteriorated, and whether fatigue, softening, or microcracks have occurred. Typically... k The spring will shrink over time, indicating that it has softened to some extent, potentially due to fatigue, creep, or material damage. If... k An abnormally large increase may indicate abnormal structural jamming, causing irregular motion. Instantaneous stiffness can be observed from the slope of the plotted bivariate curve. k The changes.

[0050] Mid-section pre-tightening deformation This indicator is calculated by reversing the mid-section operating point to the zero-force position, representing the equivalent initial compression of the spring when there is no external force. This metric primarily measures whether the spring has undergone permanent deformation. Typically... It will decrease over time, indicating reduced spring preload, which may lead to insufficient initial energy storage. If An abnormally large increase indicates an abnormal structural offset, resulting in increased load on the mechanism.

[0051] Hysteresis energy loss This is the area enclosed by the two loops, representing the energy lost by the spring during loading and unloading. This indicator primarily measures the degree of energy loss. Typically... It will increase with usage time, indicating greater energy loss, commonly caused by poor lubrication and material aging. If If the value decreases abnormally, it may indicate a sensor malfunction or a data anomaly.

[0052] Spring available energy This represents the effective energy that can actually be used to drive the circuit breaker to operate. This indicator primarily measures the effective work capacity provided by the spring to the mechanism. Typically... The spring tension will decrease over time, commonly due to decreased spring stiffness, increased hysteresis, and reduced preload. If... If the abnormal increase is significant, it may indicate a sensor malfunction or data anomaly.

[0053] As spring circuit breakers age, their spring stiffness weakens, preload drift decreases, manifesting as creep or permanent deformation; meanwhile, hysteresis increment rate loss increases, and the available energy of the spring decreases. Therefore, the spring condition assessment should comprehensively evaluate these four parameters. These key parameters not only reflect the spring's own elastic capacity but also, in conjunction with its operation within the circuit breaker, indicate whether the spring can complete the opening or closing action.

[0054] Based on the above parameters, calculate the following four main health indicators of the spring: Stiffness retention rate: , Preload drift rate: , Hysteresis increment rate: , Energy deficit rate: , Wherein, the superscript (0) represents the data baseline recorded during initial commissioning, therefore, , , , These represent the parameters of the spring when it left the factory. As the spring circuit breaker ages, the main indicators of the spring will gradually deviate from their initial values. The greater the deviation, the greater the spring wear.

[0055] S5: Based on the main health indicators obtained from the above key parameters, formulate evaluation rules and assess the spring state.

[0056] like Figure 3 As shown, the specific steps include the following: S51: If at least one health indicator is above 30%, the output status is poor; if each health indicator is below 30%, proceed to step S52.

[0057] S52: Calculate the average of all major health indicators. .

[0058] S53: Calculating Collaborative Rewards ,in ,Right now m This represents the minimum value of the four indicators, with a weight of 0.3, which can be adjusted according to the actual situation. This item indicates that if all four indicators are below 10%, a bonus is awarded. The significance of this item is to reward a high degree of consistency among the indicators.

[0059] S54: Calculate Imbalance Penalty This item indicates that if the four main health indicators deviate too much and become unbalanced, points will be deducted to prevent individual indicators from showing deviations, but this will affect the calculation of the average. This refers to the average value. 0.15 is the weight, which can be adjusted according to the actual situation.

[0060] S55: Calculate the coupling results The maximum value operation is used to avoid Sum Output a negative value.

[0061] S56: According to Sum The numerical output evaluation results.

[0062] The evaluation results can be selected from the following output criteria: If If the output state is excellent, it indicates that the spring is in excellent condition; if If the output status is "good", it indicates that the spring is in good condition and normal maintenance and repair can be arranged; if... If the output status is "medium", it means the spring is in a medium condition and requires enhanced monitoring and maintenance if necessary; otherwise, the output status is "poor", indicating that maintenance or spring replacement is required.

[0063] The data calculation and status evaluation in steps S2-S5 can be automatically completed by computer software. The software can be implemented based on the MATLAB platform, running on an industrial control computer or host computer, supporting a data sampling frequency of no less than 2 kHz, a data resolution of 16 bits or higher, and a calculation delay of no more than 10 ms within a single operation cycle. The software reads the output signals of the pressure sensor and linear velocity sensor in real time through a standard communication interface, and stores the raw time series data, spring deformation, force-deformation hysteresis loop, characteristic parameters, and evaluation results. The storage medium is a computer-readable storage medium, including a hard disk, solid-state storage, or industrial-grade flash memory, with an effective storage capacity of no less than 1 TB, sufficient to meet the long-term storage needs of multiple operation cycles and historical baseline data.

[0064] The core of this invention lies in constructing a spring health assessment system that ranges from minimizing sensor perception to mechanism-driven decision-making, and innovatively proposes a binary analysis framework centered on the force-displacement hysteresis loop. By extracting spring feature points throughout the entire closing and energy storage process, a system is constructed... , , , The model uses four physical indicators to quantitatively assess spring stiffness retention rate, preload drift rate, hysteresis increment rate, and energy deficit rate. Based on energy conservation and spring mechanics, this model overcomes the shortcomings of traditional empirical diagnostic methods that rely solely on current waveforms or mechanical travel signals and cannot reflect the true decay mechanism.

[0065] Secondly, this invention designs a minimal sensing system that relies on only two types of signals (spring pressure and crank arm linear velocity). This strategy significantly simplifies the sensor deployment and debugging process, while the use of a first-order model simplifies the computational load, reduces the memory requirements of the computing device, ensures high robustness and cross-device portability of loop feature extraction, and enables online real-time evaluation of the spring.

[0066] Furthermore, based on the extracted physical quantitative indicators, an evaluation standard based on the comprehensive health index of springs was constructed to achieve multi-feature fusion and trend prediction. By standardizing the ratio characteristics such as stiffness retention rate, preload drift rate, hysteresis increment rate, and energy deficit rate, early spring degradation, hysteresis anomalies, and stiffness mutations can be identified online, realizing the transformation from condition monitoring to life prediction. This model has good small sample adaptability and interpretability, and can collaborate with circuit breaker operation monitoring platforms to achieve real-time early warning and intelligent decision support for spring conditions. It avoids the inefficiency and lag of traditional manual inspections and periodic disassembly tests, realizing the transformation from static maintenance to dynamic predictive maintenance, and providing highly reliable and low-cost key technical support for the digital health management of smart substations and UHV equipment.

[0067] In this specification, the illustrative expressions of the terms do not necessarily refer to the same embodiments. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments.

[0068] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for evaluating the spring state in a spring circuit breaker based on a binary loop, characterized in that, Includes the following steps: S1: Within one operating cycle of the spring circuit breaker, record the start time of the actuator sequentially. t 1. Time of termination of the executing agency t 3 and the end of spring energy storage t 2 ; S2: In t 1~ t 2 Within a given time period, a pressure sensor is used to collect the pressure value at the end of the spring in real time, which is recorded as follows: F s ( t A linear velocity sensor is used to collect the linear velocity at the end of the crank arm of the actuator in real time. And based on this linear velocity, the displacement of the spring end relative to its natural state is approximately calculated, denoted as . x ( t ); S3: with x ( t () is the x-axis, F s ( t Establish a two-dimensional coordinate system with the vertical axis as the coordinate, based on the point set collected in step S2 { x ( t ), F s ( t Draw a binary hysteresis loop; S4: Calculate the key parameters based on the binary loop; S5: Develop evaluation rules based on the key parameters and assess the spring state.

2. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 1, characterized in that, In step S1, the start time of the actuator t 1、 When the executing agency stops t 3 and the end of spring energy storage t 2 The definition method is as follows: S11: Select a minimum speed value and define it as the linear velocity threshold at the end of the actuator crank arm. ; S12: During one operating cycle of the spring circuit breaker, the linear velocity at the end of the actuator crank arm exceeds the linear velocity threshold. The time is t 1. With t After 1 moment, the linear velocity at the end of the actuator crank arm is first less than the linear velocity threshold. And last for a specified time t The time after 0 is t 3, with t After 3 seconds, the linear velocity at the end of the actuator crank arm is again less than the linear velocity threshold. And last for a specified time t The time after 0 is t 2.

3. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 2, characterized in that: The linear velocity threshold The value range is 0.02~0.03 m / s; the specified time t The value of 0 ranges from 50 to 60 ms.

4. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 1, characterized in that, In step S2, the end of the spring is displaced. x ( t The calculation method for ) is as follows: S21: Calculate the conversion coefficient between the movement distance of the actuator crank arm and the displacement of the spring end. ; S22: Using the aforementioned conversion coefficient The displacement at the end of the spring is approximated using a first-order model. x ( t ) and the linear velocity at the end of the actuator crank arm The relationship is used to calculate the displacement of the spring end at different times. x ( t ).

5. The spring state evaluation method in a spring circuit breaker based on a binary loop according to claim 4, characterized in that, The conversion coefficient In the formula, x For any tiny time range t 01 ~ t 02 The deformation of the inner spring, where, t 01 and t 02 These represent the start and end times within any infinitesimal time interval, respectively.

6. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 4, characterized in that: The first-order model in step S22 is In the formula, x 0 represents the initial displacement of the spring end, and τ represents the time integral variable.

7. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 1, characterized in that, In step S4, the key parameters include instantaneous stiffness. k Mid-section pre-tightening deformation Hysteresis energy loss And the energy available to the spring ,in, ； ； ； ； In the formula, Mid-section stiffness is the spring deformation. x ( t () is the maximum value The instantaneous stiffness at half its value; When the spring deformation x ( t () is the maximum value The static pressure of the spring at half its capacity, dF s dx represents the infinitesimal pressure at the end of the spring, and dx represents the infinitesimal displacement of the end of the spring relative to its natural state. F s (t+1) represents the pressure value at the end of the spring at time t+1, F s (t) represents the pressure value at the end of the spring at time t, x(t+1) represents the displacement of the end of the spring relative to its natural state at time t+1, and x(t) represents the displacement of the end of the spring relative to its natural state at time t. i This represents the i-th x-coordinate after dividing the hysteresis loop into a series of infinitesimal curve segments along the x-axis; i+1 x represents i The next x-coordinate; F s,i x represents i The ordinate value of the hysteresis loop corresponding to the position; F s,i+1 x represents i+1 The vertical coordinate value of the hysteresis loop corresponding to the position, x(t1) represents the x-coordinate at the moment the actuator starts. The x-coordinate represents the moment when the actuator stops.

8. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 7, characterized in that, Step S4 further includes calculating the spring's primary health index: stiffness retention rate. Preload drift rate Hysteresis Increment Rate Energy deficit rate ,in, ； ； ； ； In the formula, , , , These represent the spring's interrupted stiffness at the time of manufacture, the amount of preload deformation in the middle section, the hysteresis energy loss, and the spring's usable energy, respectively.

9. The spring state evaluation method for a spring circuit breaker based on a binary loop according to claim 8, characterized in that, The evaluation rules in step S5 include the following steps: S51: If at least one health indicator is above 30%, the output status is poor; if each health indicator is below 30%, proceed to step S52. S52: Calculate the average of all major health indicators. ; S53: Calculating Collaborative Rewards ,in ; S54: Calculate Imbalance Penalty ; S55: Calculate the coupling results ; S56: According to Sum The numerical output evaluation results.

10. The spring state evaluation method in a spring circuit breaker based on a binary loop according to claim 9, characterized in that, The output criteria for the evaluation results are: if If the output state is good, then the output state is excellent; if If the output status is good, then the output status is good; If the output state is 0, the output state is 0; otherwise, the output state is 0.

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