Temperature rise performance evaluation method and system for switchgear

Abstract

The invention discloses a temperature rise performance evaluation method and system for switch equipment, and the method comprises the steps: building a switch equipment model, carrying out the temperature rise simulation based on the switch equipment model, and determining a temperature rise exceeding weak point; obtaining key structure material parameters of the switch equipment, and comparing the key structure material parameters with the critical structure material parameters to pre-evaluate the switch equipment; wherein when the material parameters of the key structure of the switchgear exceed the critical parameters, the temperature rise performance of the switchgear is pre-evaluated to be unqualified, and the switchgear is listed as a key detection object to carry out an experiment; if the critical parameter is not exceeded, pre-evaluating as qualified and carrying out experimental verification; and carrying out a temperature rise test to obtain temperature rise data of the temperature rise exceeding weak point, and carrying out temperature rise performance evaluation based on the temperature rise data. According to the method, the temperature rise performance of the switch equipment can be efficiently evaluated based on the temperature rise simulation result, the key structure material parameters, the initial current increasing method and the prediction algorithm.

Description

Technical Field

[0001] The present invention relates to the technical field of power tests, and more specifically, to a method and system for evaluating the temperature rise performance of a switching device. Background Art

[0002] The temperature rise test is an important test in the type tests of switching devices and complete switchgear assemblies. It is used to check whether the device can normally conduct the rated current. The test time for low-voltage integrated distribution boxes is more than 5 hours, and the test time for high-voltage switchgear is more than 8 hours, which is time-consuming and has low work efficiency. Currently, the basis for determining the stability of the temperature rise is still that the temperature rise change value within 1 hour is within 1 K. There is no analysis of the relationship between the temperature rise of the switching device and the structural material parameters, and no pre-evaluation of the temperature rise state is carried out by applying the critical structural material parameters of the switching device. Nor is there a rapid evaluation by combining the internal and external temperature rise distribution laws and the exponential change law of the temperature rise of the switching device.

[0003] Based on the current situation of a relatively high unqualified rate of the temperature rise in the sampling inspection results of switching devices, it is urgent to carry out an analysis of the influence of the thermal performance of switching devices; the batch tests of switching devices are time-consuming, with high experimental losses and costs. It is urgent to carry out a rapid evaluation of the temperature rise performance of switching devices to shorten the test time and improve work efficiency. Summary of the Invention

[0004] The present invention provides a method and system for evaluating the temperature rise performance of a switching device to solve the problem of how to efficiently evaluate the temperature rise performance of a switching device.

[0005] To solve the above problems, according to one aspect of the present invention, a method for evaluating the temperature rise performance of a switching device is provided. The method includes:

[0006] Establish a switching device model, and perform temperature rise simulation based on the switching device model to determine the weak points where the temperature rise exceeds the standard;

[0007] Obtain the key structural material parameters of the switching device, and compare the key structural material parameters with the critical structural material parameters to pre-evaluate the switching device; wherein, when the key structural material parameters of the switching device exceed the critical parameters, pre-evaluate that the temperature rise performance of the switching device is unqualified and list it as a key inspection object for experiments; when the key structural material parameters of the switching device do not exceed the critical parameters, pre-evaluate as qualified and carry out experimental verification; conduct a temperature rise test, obtain the temperature rise data of the weak points where the temperature rise exceeds the standard, and perform temperature rise performance evaluation based on the temperature rise data.

[0008] Preferably, the weak points where the temperature rise exceeds the standard include: the connection points of the wiring terminals and copper bars of the switching device.

[0009] Preferably, the method further includes:

[0010] Simulate and analyze the variation law of the temperature rise state of the switchgear with the key structural material parameters, and extract the critical structural material parameters when the temperature rise exceeds the standard, so as to obtain the critical structural material parameters.

[0011] Preferably, the key structural material parameters include: the cross-sectional area of the outgoing copper busbar of the switchgear, the width of the circuit breaker, and the circuit breaker interval.

[0012] Preferably, comparing the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear to be tested includes:

[0013] When the cross-sectional area of the outgoing copper busbar, the width of the circuit breaker, or the circuit breaker interval of the switchgear is less than the corresponding critical structural material parameters, it is determined that the pre-evaluation result is unqualified; otherwise, it is determined that the pre-evaluation result is qualified.

[0014] Preferably, when conducting the temperature rise test, apply a preset multiple of the rated current to the switchgear at the initial stage. After the temperature rise reaches the preset temperature rise value, restore the applied current to the rated value, and obtain the temperature rise data of the weak point where the temperature rise exceeds the standard after the current is restored to the rated value, so as to conduct the temperature rise performance evaluation based on the temperature rise data.

[0015] Preferably, the temperature rise performance evaluation based on the temperature rise data includes:

[0016] S1, set the initial value τ1 and assign τ = τ1;

[0017] S2, calculate the temperature rise value τ based on the temperature rise data of the weak point where the temperature rise exceeds the standard and the least squares method p ;

[0018] S3, judge whether |τ - τ p | ≤ 1 is satisfied; where, if it is satisfied, then determine τ r = τ, and conduct the temperature rise performance evaluation based on τ r ; if it is not satisfied, then enter S4;

[0019] S4, judge whether τ p > τ is satisfied; where, if it is satisfied, then set τ2 = τ p , assign τ = τ2, and enter S2 to recalculate; if it is not satisfied, then enter S5;

[0020] S5, judge whether τ - τ e > 1 is satisfied; where, if it is satisfied, then set τ2 = τ - 1, assign τ = τ2, and enter S2 to recalculate; if it is not satisfied, then determine τ r = τ, and conduct the temperature rise performance evaluation based on τ r ;

[0021] where τ is the set value of temperature rise, τ p is the calculated value of temperature rise, τ r is the predicted value of temperature rise, τ e is the measured value of temperature rise; τ1 and τ2 are the intermediate values of temperature rise.

[0022] According to another aspect of the present invention, there is provided a temperature rise performance evaluation system for a switchgear, the system comprising:

[0023] A weak point determination unit for temperature rise exceeding the standard, which is used to establish a switchgear model and perform temperature rise simulation based on the switchgear model to determine the weak points where the temperature rise exceeds the standard;

[0024] A pre-evaluation unit, which is used to obtain the key structural material parameters of the switchgear and compare the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear; wherein, when the key structural material parameters of the switchgear exceed the critical parameters, the pre-evaluation result of the temperature rise performance of the switchgear is unqualified and it is listed as a key detection object for experiments; when the key structural material parameters of the switchgear do not exceed the critical parameters, the pre-evaluation is qualified and experimental verification is carried out; a temperature rise performance evaluation unit, which is used to conduct a temperature rise test to obtain the temperature rise data of the weak points where the temperature rise exceeds the standard, so as to evaluate the temperature rise performance based on the temperature rise data.

[0025] Preferably, the weak points where the temperature rise exceeds the standard include: the connection points of the wiring terminals and copper bars of the switchgear.

[0026] Preferably, the system further comprises:

[0027] A critical structural material parameter acquisition unit, which is used to simulate and analyze the variation law of the temperature rise state of the switchgear with the key structural material parameters, and extract the critical structural material parameters when the temperature rise exceeds the standard, so as to obtain the critical structural material parameters.

[0028] Preferably, the key structural material parameters include: the cross-sectional area of the outgoing copper bar of the switchgear, the width of the circuit breaker, and the circuit breaker interval.

[0029] Preferably, the pre-evaluation unit compares the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear to be tested, including:

[0030] When the cross-sectional area of the outgoing copper bar, the width of the circuit breaker, or the circuit breaker interval of the switchgear is less than the corresponding critical structural material parameters, it is determined that the pre-evaluation result is unqualified; otherwise, it is determined that the pre-evaluation result is qualified.

[0031] Preferably, when the temperature rise performance evaluation unit conducts a temperature rise test, it applies a rated current multiplied by a preset multiple to the switchgear at the initial stage. After the temperature rise reaches the preset temperature rise value, the applied current is restored to the rated value, and the temperature rise data of the weak points where the temperature rise exceeds the standard after the current is restored to the rated value is obtained, so as to evaluate the temperature rise performance based on the temperature rise data.

[0032] Preferably, the temperature rise performance evaluation unit evaluates the temperature rise performance based on the temperature rise data, including:

[0033] S1, set an initial value τ1 and assign τ = τ1;

[0034] S2, calculate the temperature rise value τ based on the temperature rise data of the weak points where the temperature rise exceeds the standard and the least squares method p ;

[0035] S3, judge whether |τ - τ p | ≤ 1 is satisfied; where, if it is satisfied, determine τ r = τ, and conduct a temperature rise performance evaluation based on τ r ; if not satisfied, enter S4;

[0036] S4, judge whether τ p > τ is satisfied; where, if it is satisfied, set τ2 = τ p , assign τ = τ2, and enter S2 to recalculate; if not satisfied, enter S5;

[0037] S5, judge whether τ - τ e > 1 is satisfied; where, if it is satisfied, set τ2 = τ - 1, assign τ = τ2, and enter S2 to recalculate; if not satisfied, determine τ r = τ, and conduct a temperature rise performance evaluation based on τ r ;

[0038] Among them, τ is the temperature rise set value, τ p is the temperature rise calculated value, τ r is the temperature rise predicted value, τ e is the temperature rise measured value; τ1 and τ2 are the temperature rise intermediate values.

[0039] The present invention provides a method and system for evaluating the temperature rise performance of a switching device, including: establishing a switching device model, performing temperature rise simulation based on the switching device model, and determining the weak points where the temperature rise exceeds the standard; obtaining the key structural material parameters of the switching device, and comparing the key structural material parameters with the critical structural material parameters to pre-evaluate the switching device; wherein, when the key structural material parameters of the switching device exceed the critical parameters, the pre-evaluation of the temperature rise performance of the switching device is unqualified, and it is listed as a key detection object for experiments; when the key structural material parameters of the switching device do not exceed the critical parameters, the pre-evaluation is qualified and experimental verification is carried out; performing a temperature rise test, obtaining the temperature rise data of the weak points where the temperature rise exceeds the standard, and evaluating the temperature rise performance based on the temperature rise data. The present invention can solve the problems of long time consumption and low working efficiency in the temperature rise test of the switching device, and can efficiently evaluate the temperature rise performance of the switching device based on the temperature rise simulation results, key structural material parameters, the method of increasing the initial current, and the prediction algorithm. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The exemplary embodiments of the present invention can be more fully understood by reference to the following drawings:

[0041] Figure 1 FIG. 100 is a flowchart of a method for evaluating the temperature rise performance of a switching device according to an embodiment of the present invention;

[0042] Figure 2 FIG. 13 is a schematic diagram of a simulation of a method for pre-evaluating the temperature rise state of a switching device according to an embodiment of the present invention;

[0043] Figure 3 FIG. 17 is a block diagram of a method for quickly evaluating the temperature rise performance of a switching device according to an embodiment of the present invention;

[0044] Figure 4 FIG. 21 is an effect diagram of quickly evaluating the temperature rise performance of a switching device according to an embodiment of the present invention;

[0045] Figure 5 FIG. 25 is an effect diagram of quickly evaluating the temperature rise performance by applying an increased initial current according to an embodiment of the present invention;

[0046] Figure 6 FIG. 29 is a schematic structural diagram of a system 600 for evaluating the temperature rise performance of a switching device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] Reference is now made to the accompanying drawings to describe exemplary embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely, and to fully convey the scope of the present invention to those skilled in the art. The terms in the exemplary embodiments shown in the drawings are not intended to limit the present invention. In the drawings, the same units / components are denoted by the same reference numerals.

[0048] Unless otherwise specified, the terms used herein (including scientific and technical terms) have the ordinary meaning understood by those skilled in the art. In addition, it can be understood that the terms defined in the commonly used dictionary should be understood as having a meaning consistent with the context of their related fields, and should not be understood as idealized or overly formal meanings.

[0049] Figure 1 It is a flowchart of a method 100 for evaluating the temperature rise performance of a switching device according to an embodiment of the present invention. As Figure 1 shown, the method for evaluating the temperature rise performance of the switching device provided by the embodiment of the present invention can solve the problems of long duration and low working efficiency of the temperature rise test of the switching device. It can solve the problems of long duration and low working efficiency of the temperature rise test of the switching device, and can efficiently evaluate the temperature rise performance of the switching device based on the temperature rise simulation results, key structural material parameters, the method of increasing the initial current, and the prediction algorithm. The method 100 for evaluating the temperature rise performance of the switching device provided by the embodiment of the present invention starts at step 101. At step 101, a switching device model is established, and temperature rise simulation is performed based on the switching device model to determine the weak points where the temperature rise exceeds the standard.

[0050] Preferably, the weak points where the temperature rise exceeds the standard include: the connection points between the wiring terminals and copper bars of the switching device.

[0051] At step 102, the key structural material parameters of the switching device are obtained, and the key structural material parameters are compared with the critical structural material parameters to pre-evaluate the switching device. Among them, when the key structural material parameters of the switching device exceed the critical parameters, the temperature rise performance of the switching device is pre-evaluated as unqualified and listed as a key detection object for experiments; when the key structural material parameters of the switching device do not exceed the critical parameters, it is pre-evaluated as qualified and experimental verification is carried out.

[0052] Preferably, the method further includes:

[0053] Simulate and analyze the variation law of the temperature rise state of the switching device with the key structural material parameters, and extract the critical structural material parameters when the temperature rise exceeds the standard to obtain the critical structural material parameters.

[0054] Preferably, the key structural material parameters include: the cross-sectional area of the outgoing copper busbar of the switchgear, the width of the circuit breaker, and the circuit breaker interval.

[0055] Preferably, comparing the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear to be tested includes:

[0056] When the cross-sectional area of the outgoing copper busbar of the switchgear, the width of the circuit breaker, or the circuit breaker interval is less than the corresponding critical structural material parameters, it is determined that the pre-evaluation result is unqualified; otherwise, the pre-evaluation result is determined to be qualified.

[0057] In the present invention, in the pre-evaluation method of the switchgear temperature rise state, the variation law of the switchgear temperature rise state with the key structural material parameters is simulated and analyzed, the critical structural material parameters when the temperature rise exceeds the standard are extracted, and then the relationship between the key structural material parameters and the critical parameters of the switchgear is compared to pre-evaluate its temperature rise state. Among them, the key structural material parameters include: the cross-sectional area of the outgoing copper busbar of the switchgear, the width of the circuit breaker, and the circuit breaker interval, etc., which directly affect the heat dissipation process of the switchgear. When the key structural material parameters of the switchgear exceed the critical parameters, it is pre-evaluated that the temperature rise performance of the switchgear is unqualified and it is listed as a key inspection object for experiments. When the temperature rise exceeds the limit, its unqualified state is verified and the test is immediately stopped, narrowing the scope of attention and improving the result judgment efficiency; when the parameters of the sample are within the normal range, it can be pre-evaluated as qualified and experimental verification is carried out.

[0058] In step 103, a temperature rise test is carried out to obtain the temperature rise data of the temperature rise exceeding the standard weak point, so as to evaluate the temperature rise performance based on the temperature rise data.

[0059] Preferably, when the method conducts a temperature rise test, a preset multiple of the rated current is applied to the switchgear in the initial stage. After the temperature rise rises to the preset temperature rise value, the applied current is restored to the rated value, and the temperature rise data of the temperature rise exceeding the standard weak point after the current is restored to the rated value is obtained, so as to evaluate the temperature rise performance based on the temperature rise data.

[0060] Preferably, the evaluation of the temperature rise performance based on the temperature rise data includes:

[0061] S1, set the initial value τ1 and assign τ = τ1;

[0062] S2, calculate the temperature rise value τ based on the temperature rise data of the temperature rise exceeding the standard weak point and the least squares method p ;

[0063] S3, judge whether |τ - τ p | ≤ 1 is satisfied; where, if satisfied, it is determined that τ r = τ, and based on τ rConduct a temperature rise performance assessment; if not satisfied, enter S4;

[0064] S4, determine whether τ p >τ; where, if satisfied, set τ2 = τ p , assign τ = τ2, and enter S2 to recalculate; if not satisfied, enter S5;

[0065] S5, determine whether τ - τ e >1; where, if satisfied, set τ2 = τ - 1, assign τ = τ2, and enter S2 to recalculate; if not satisfied, determine τ r = τ, and based on τ r Conduct a temperature rise performance assessment;

[0066] Among them, τ is the temperature rise set value, τ p is the temperature rise calculated value, τ r is the temperature rise predicted value, τ e is the measured temperature rise value; τ1 and τ2 are the intermediate temperature rise values.

[0067] In the present invention, a switch model is established and simulated to determine the weak points of the switchgear with excessive temperature rise. The weak points of the switchgear with excessive temperature rise include parts such as the switchgear wiring terminals and copper bar connection points, which are the key attention objects during the temperature rise performance assessment.

[0068] In the present invention, the temperature rise τ of the switchgear has an exponential relationship with time t, and after linearization, it satisfies a linear relationship. The weak points of the switchgear with excessive temperature rise are obtained from the temperature rise simulation results, and then prediction algorithms such as the least squares method are used to calculate the temperature rise time coefficient T and the stable temperature rise τ r from the previous temperature rise data of the measuring points, and then the fitting function of the temperature is obtained to realize the rapid assessment of the temperature rise performance.

[0069] In the present invention, there are differences in the fitting curves obtained by using the measured data at different times. The longer the measured time, the smaller the prediction error and the better the curve fitting degree, but the reduced experimental time is less. The prediction error value can be set, and the measured data that meets this accuracy requirement is sufficient for fitting, and it can effectively shorten the required experimental time and improve the work efficiency.

[0070] In the present invention, during the temperature rise test, at the initial stage of the switchgear, the temperature rise is increased to the preset temperature rise value by applying a preset multiple (1.2 - 1.5 times) of the rated current, and then the current is restored to the rated value. The stable temperature rise is predicted by using some of the measured data after the current is restored to the stable value, and the required experimental time is further shortened on the basis of ensuring the prediction accuracy.

[0071] Combined with Figure 2As shown, in an embodiment of the present invention, to conduct a pre - evaluation of the temperature rise state of switchgear, it is necessary to establish a finite - element model of the switchgear, simulate and obtain the variation law of the rated - current temperature - rise distribution under different key structural material parameters, extract the critical structural material parameters of the switchgear, compare the relationship between the key structural material parameters of the sample and the critical parameters, and pre - evaluate the temperature - rise state of the switchgear.

[0072] In one embodiment, the key structural material parameters include the cross - sectional area of the outgoing copper busbar, the width of the circuit breaker, and the circuit - breaker spacing, etc. On the basis of leaving a margin, the critical parameters of a 400V / 630A low - voltage integrated distribution box are: the cross - sectional area of the outgoing copper busbar is 320mm 2 , the width of the circuit breaker is 240mm, and the circuit - breaker spacing is 22mm. When the size of the low - voltage integrated distribution box is smaller than the critical parameters, it can be pre - evaluated as unqualified, listed as a key - attention object for experiments, and the experiment is stopped when the temperature rise exceeds the limit value; for products pre - evaluated as qualified, further experiments are carried out for verification.

[0073] Combined with Figure 3 As shown, in an embodiment of the present invention, the weak points of excessive temperature rise are obtained from the temperature - rise simulation results of the switchgear, and then the temperature - rise time coefficient T and the stable temperature rise τ of the switchgear measurement points are deduced from the previous temperature - rise data of the measurement points by using the least - squares method r , and then the fitting function of the temperature rise of the measurement points is obtained to realize the rapid evaluation of the temperature - rise performance. The temperature - rise prediction effect of the proposed method is as Figure 4 shown.

[0074] Among them, the evaluation of the temperature - rise performance based on the temperature - rise data includes:

[0075] S1, set the initial value τ1, and assign τ = τ1;

[0076] S2, calculate the temperature rise value τ based on the temperature - rise data of the weak points of excessive temperature rise and the least - squares method p ;

[0077] S3, judge whether |τ - τ p |≤1 is satisfied; among them, if it is satisfied, then determine τ r = τ, and conduct the temperature - rise performance evaluation based on τ r ; if it is not satisfied, then enter S4;

[0078] S4, judge whether τ p >τ is satisfied; among them, if it is satisfied, then set τ2 = τ p , assign τ = τ2, and enter S2 to recalculate; if it is not satisfied, then enter S5;

[0079] S5, judge whether τ - τ e> 1; where, if it is satisfied, set τ2 = τ - 1, assign τ = τ2, and enter S2 to recalculate; if not satisfied, determine τ r = τ, and based on τ r Conduct temperature rise performance evaluation;

[0080] where, τ is the temperature rise set value, τ p is the temperature rise calculated value, τ r is the temperature rise predicted value, τ e is the measured temperature rise value; τ1 and τ2 are the intermediate temperature rise values.

[0081] In one embodiment, the fitting curves obtained by applying the measured data at different times are different. The longer the measured time, the smaller the prediction error and the better the curve fitting degree, but the reduced experimental time saved. Based on the fact that the temperature rise values of the qualified samples in the temperature rise test are often more than 3K lower than the temperature rise limit, the prediction error value can be set to 3K. The measured data for fitting that meets this accuracy requirement is sufficient, and it effectively saves the actual experimental time and improves work efficiency.

[0082] Such as Figure 5 shown, in one embodiment, the distribution box initially applies n times the rated current, the temperature rise rises to a higher value and the current returns to the rated value. The measured data after the current returns to the stable value is used to predict the stable temperature rise, and the required measured time is further shortened on the basis of ensuring the prediction accuracy.

[0083] Figure 6 is a schematic structural diagram of the temperature rise performance evaluation system 600 of the switchgear according to the embodiment of the present invention. Such as Figure 6 shown, the temperature rise performance evaluation system 600 of the switchgear provided by the embodiment of the present invention includes: a temperature rise exceeding standard weak point determination unit 601, a pre-evaluation unit 602, and a temperature rise performance evaluation unit 603.

[0084] Preferably, the temperature rise exceeding standard weak point determination unit 601 establishes a switchgear model and conducts temperature rise simulation based on the switchgear model to determine the temperature rise exceeding standard weak points.

[0085] Preferably, the temperature rise exceeding standard weak points include: the connection points of the switchgear wiring terminals and copper bars.

[0086] Preferably, the pre-evaluation unit 602 is used to obtain the key structural material parameters of the switchgear and compare the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear. Wherein, when the key structural material parameters of the switchgear exceed the critical parameters, the temperature rise performance of the switchgear is pre-evaluated as unqualified and listed as a key detection object for experiments; when the key structural material parameters of the switchgear do not exceed the critical parameters, it is pre-evaluated as qualified and experimental verification is carried out.

[0087] Preferably, the system further includes:

[0088] A critical structural material parameter acquisition unit, configured to simulate and analyze the variation law of the temperature rise state of the switching device with the key structural material parameters, and extract the critical structural material parameters when the temperature rise exceeds the standard, so as to obtain the critical structural material parameters.

[0089] Preferably, the pre-evaluation unit 602 compares the key structural material parameters with the critical structural material parameters to pre-evaluate the switching device to be tested, including:

[0090] When the cross-sectional area of the outgoing copper busbar, the width of the circuit breaker, or the circuit breaker interval of the switching device is less than the corresponding critical structural material parameters, it is determined that the pre-evaluation result is unqualified; otherwise, it is determined that the pre-evaluation result is qualified.

[0091] Preferably, the key structural material parameters include: the cross-sectional area of the outgoing copper busbar of the switching device, the width of the circuit breaker, and the circuit breaker interval.

[0092] Preferably, the temperature rise performance evaluation unit 603 is configured to perform a temperature rise test to obtain the temperature rise data of the weak points where the temperature rise exceeds the standard, so as to perform a temperature rise performance evaluation based on the temperature rise data.

[0093] Preferably, when performing the temperature rise test, the temperature rise performance evaluation unit applies a rated current of a preset multiple to the switching device at the initial stage. After the temperature rise rises to the preset temperature rise value, the applied current is restored to the rated value, and the temperature rise data of the weak points where the temperature rise exceeds the standard after the current is restored to the rated value is obtained, so as to perform a temperature rise performance evaluation based on the temperature rise data.

[0094] Preferably, the temperature rise performance evaluation unit performs a temperature rise performance evaluation based on the temperature rise data, including:

[0095] S1, set an initial value τ1, and assign τ = τ1;

[0096] S2, calculate the temperature rise value τ based on the temperature rise data of the weak points where the temperature rise exceeds the standard and the least squares method p ;

[0097] S3, determine whether |τ - τ p | ≤ 1 is satisfied; where, if satisfied, determine τ r = τ, and perform a temperature rise performance evaluation based on τ r ; if not satisfied, enter S4;

[0098] S4, determine whether τ p > τ is satisfied; where, if satisfied, set τ2 = τ p, assign τ = τ2, and enter S2 for recalculation; if not satisfied, enter S5;

[0099] S5, determine whether τ - τ e > 1; where, if satisfied, set τ2 = τ - 1, assign τ = τ2, and enter S2 for recalculation; if not satisfied, determine τ r = τ, and based on τ r carry out the temperature rise performance evaluation;

[0100] where, τ is the temperature rise set value, τ p is the temperature rise calculated value, τ r is the temperature rise predicted value, τ e is the temperature rise measured value; τ1 and τ2 are the temperature rise intermediate values.

[0101] The temperature rise performance evaluation system 600 of the switchgear in the embodiment of the present invention corresponds to the Figure 6 temperature rise performance evaluation method 100 of the switchgear according to the embodiment of the present invention, and will not be elaborated here.

[0102] The present invention has been described by referring to a few embodiments. However, as is known to those skilled in the art, other embodiments equivalent to those disclosed above of the present invention equally fall within the scope of the present invention.

[0103] Generally, all terms used in the present invention are interpreted according to their ordinary meanings in the technical field, unless otherwise clearly defined therein. All references to "a / the [device, component, etc.]" are open - interpreted as at least one instance of the device, component, etc., unless otherwise clearly stated. The steps of any method disclosed here do not necessarily have to be run in the exact order disclosed, unless clearly stated.

[0104] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer - usable storage media (including but not limited to disk memory, CD - ROM, optical memory, etc.) containing computer - usable program code.

[0105] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram can be implemented by computer program instructions, and the combination of flows and / or blocks in the flowchart and / or block diagram can also be implemented. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0106] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0107] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operational steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific embodiments of the present invention, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for evaluating the temperature rise performance of a switching device, characterized in that, The method includes: Establishing a switchgear model, performing temperature rise simulation based on the switchgear model, and determining the weak points with excessive temperature rise; Obtaining the key structural material parameters of the switchgear, and comparing the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear; wherein, when the key structural material parameters of the switchgear exceed the critical parameters, the pre-evaluation result of the temperature rise performance of the switchgear is unqualified, and it is listed as a key detection object for experiments; when the key structural material parameters of the switchgear do not exceed the critical parameters, the pre-evaluation is qualified and experimental verification is carried out; Performing a temperature rise test to obtain the temperature rise data of the weak points with excessive temperature rise, so as to evaluate the temperature rise performance based on the temperature rise data.

2. The method according to claim 1, wherein The weak points with excessive temperature rise include the connection points of the switchgear wiring terminals and copper bars.

3. The method according to claim 2, wherein The method further includes: Simulating and analyzing the variation law of the switchgear temperature rise state with the key structural material parameters, and extracting the critical structural material parameters when the temperature rise exceeds the standard to obtain the critical structural material parameters.

4. The method according to claim 2, wherein The key structural material parameters include the cross-sectional area of the outgoing copper bar of the switchgear, the width of the circuit breaker, and the circuit breaker interval.

5. The method according to claim 2, wherein The comparison of the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear to be tested includes: When the cross-sectional area of the outgoing copper bar of the switchgear, the width of the circuit breaker, or the circuit breaker interval is less than the corresponding critical structural material parameters, it is determined that the pre-evaluation result is unqualified; otherwise, it is determined that the pre-evaluation result is qualified.

6. The method according to claim 3, characterized in that, When performing the temperature rise test, a preset multiple of the rated current is applied to the switchgear at the initial stage. After the temperature rise reaches the preset temperature rise value, the applied current is restored to the rated value, and the temperature rise data of the weak points with excessive temperature rise after the current is restored to the rated value is obtained, so as to evaluate the temperature rise performance based on the temperature rise data.

7. The method according to claim 3, wherein The evaluation of the temperature rise performance based on the temperature rise data includes: S1, setting an initial value τ1 and assigning τ = τ1; S2. Calculate the temperature rise value τ based on the temperature rise data of the weak points with excessive temperature rise and the least squares method p ; S3. Determine whether |τ - τ p | ≤ 1 is satisfied; where if it is satisfied, determine the final temperature rise prediction value τ r = τ, and based on τ r carry out the temperature rise performance evaluation; if it is not satisfied, go to S4; S4, determine whether τ is satisfied p > τ; where, if satisfied, set τ2 = τ p , assign τ = τ2, and enter S2 to recalculate; if not satisfied, enter S5; S5, determine whether τ - τ e > 1; where, if it is satisfied, set τ2 = τ - 1, assign τ = τ2, and enter S2 to recalculate; if not satisfied, determine τ r = τ, and based on τ r carry out the temperature rise performance evaluation; Among them, τ is the temperature rise set value, τ p is the temperature rise calculated value, τ r is the temperature rise predicted value, τ e is the measured temperature rise value; τ1 and τ2 are the intermediate temperature rise values.

8. A temperature rise performance evaluation system for a switching device, characterized in that, The system includes: A weak point determination unit for excessive temperature rise, which is used to establish a switchgear model, perform temperature rise simulation based on the switchgear model, and determine the weak points with excessive temperature rise; A pre-evaluation unit, which is used to obtain the key structural material parameters of the switchgear, and compare the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear; wherein, when the key structural material parameters of the switchgear exceed the critical parameters, the pre-evaluation result of the temperature rise performance of the switchgear is unqualified, and it is listed as a key detection object for experiments; when the key structural material parameters of the switchgear do not exceed the critical parameters, the pre-evaluation is qualified and experimental verification is carried out; A temperature rise performance evaluation unit, which is used to perform a temperature rise test to obtain the temperature rise data of the weak points with excessive temperature rise, so as to evaluate the temperature rise performance based on the temperature rise data.

9. The system according to claim 8, wherein The system further includes: A critical structural material parameter acquisition unit, which is used to simulate and analyze the variation law of the switchgear temperature rise state with the key structural material parameters, and extract the critical structural material parameters when the temperature rise exceeds the standard to obtain the critical structural material parameters.

10. The system according to claim 8, wherein The key structural material parameters include: the cross-sectional area of the outgoing copper busbar of the switchgear, the width of the circuit breaker, and the circuit breaker interval.

11. The system according to claim 10, wherein, The pre-evaluation unit compares the key structural material parameters with the critical structural material parameters to pre-evaluate the switchgear to be tested, including: When the cross-sectional area of the outgoing copper busbar of the switchgear, the width of the circuit breaker, or the circuit breaker interval is less than the corresponding critical structural material parameter, it is determined that the pre-evaluation result is unqualified; otherwise, it is determined that the pre-evaluation result is qualified.

12. The system according to claim 8, wherein The weak points of over-temperature rise include: the connection terminals of the switchgear and the joints of the copper busbars.

13. The system according to claim 8, wherein During the temperature rise test, the temperature rise performance evaluation unit applies a rated current multiplied by a preset multiple to the switchgear at the initial stage. After the temperature rise reaches the preset temperature rise value, the applied current is restored to the rated value, and the temperature rise data of the weak points of over-temperature rise are obtained after the current is restored to the rated value, so as to conduct a temperature rise performance evaluation based on the temperature rise data.

14. The method according to claim 8, wherein The temperature rise performance evaluation unit conducts a temperature rise performance evaluation based on the temperature rise data, including: S1, set an initial value τ1 and assign τ = τ1; S2. Calculate the temperature rise value τ based on the temperature rise data of the weak points with excessive temperature rise and the least squares method p ; S3. Determine whether |τ - τ p | ≤ 1 holds; where if it holds, determine the final temperature rise prediction value τ r = τ, and based on τ r carry out the temperature rise performance evaluation; if it does not hold, proceed to S4; S4, determine whether τ is satisfied p > τ; where, if satisfied, set τ2 = τ p , assign τ = τ2, and enter S2 to recalculate; if not satisfied, enter S5; S5, determine whether τ - τ e > 1; where, if satisfied, set τ2 = τ - 1, assign τ = τ2, and enter S2 to recalculate; if not satisfied, determine τ r = τ, and based on τ r carry out the temperature rise performance evaluation; Among them, τ is the temperature rise set value, τ p is the temperature rise calculated value, τ r is the temperature rise predicted value, τ e is the measured temperature rise value; τ1 and τ2 are the intermediate temperature rise values.

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