A reliability evaluation method and system for a vehicle-mounted fusing temperature relay

Abstract

The present invention discloses a reliability evaluation method and system for a vehicle-mounted fusing type temperature relay, including: performing an environmental aging experiment on the to-be-tested fusing type temperature relay, measuring the contact resistance between two lead terminals of the fusing type temperature relay and the insulation resistance between the lead terminals and the housing; judging whether the fusing type temperature relay deteriorates according to the contact resistance and the insulation resistance; determining the time required for the fusing type temperature relays that have deteriorated and those that have not deteriorated to deteriorate; calculating a conversion coefficient between the life under test conditions and the life under use conditions, and further obtaining the service life of the to-be-tested fusing type temperature relay. The results obtained by the three aging tests used in the present invention are more accurate, solving the problem that the reliability evaluation results of the fusing type temperature relay for high-speed trains are inaccurate both at home and abroad.

Description

Technical Field

[0001] The present invention relates to the technical field of fusing type temperature relays for rail vehicles, and particularly to a method and system for evaluating the reliability of fusing type temperature relays for vehicles. Background Art

[0002] The statements in this section merely provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, the prior art mainly conducts research on the leaf spring type temperature relays of bogies and traction motors, and has continuously innovated in aspects of temperature detection systems such as the selection of infrared temperature sensor detection devices and processors and the design of temperature acquisition sensors, and has achieved certain research results. However, there is a lack of relevant research on the variation laws of the performance of each component of the leaf spring type fusing type temperature relays of bogies and traction motors with service time, and a reliability assessment process and method for the entire life cycle have not been formed.

[0004] With the wide application of leaf spring type temperature sensors, the disadvantages of leaf spring type temperature relays have gradually emerged, that is, there are problems such as insulation breakdown, fracture of the lead rod after repeated vibration and impact, and poor sealing, resulting in frequent false alarms of the temperature relay. To solve the above problems, for the fault modes of leaf spring type temperature relays such as insulation breakdown, seal failure, and false alarms, the insulation and sealing of the structure of the fusing type temperature relay have been strengthened, and a double fuse tube parallel design has been adopted to reduce the probability of false alarms, thereby developing a fusing type temperature relay for traction motors.

[0005] However, the fusing type temperature relay will also have some problems, and the most typical one is the aging problem. The aging of the fusing type temperature relay will cause changes in its contact resistance and insulation resistance, affecting normal use and even endangering the operation safety of rail vehicles. For the research on fusing type temperature relays, domestic and foreign attention has been focused on exploring the variation laws of fusing type temperature relays with temperature, and certain results have been achieved, and at the same time, some suggestions for the design and selection of fusing type temperature relays have been put forward. However, there is still a lack of relevant research on the variation laws of the performance of fusing type temperature relays used in bogies and traction motors and the performance of internal key components with service time. Summary of the Invention

[0006] To solve the above problems, the present invention proposes a method and system for evaluating the reliability of fusing type temperature relays for vehicles. Based on the deterioration times of the contact resistance and insulation resistance of the fusing type temperature relay in three different aging environments, the aging time ranges of the fusing type temperature relay in the actual working environment are obtained respectively, improving the accuracy of reliability assessment.

[0007] According to the first aspect of the embodiments of the present invention, a method for evaluating the reliability of a vehicle fuse type temperature relay is provided, including:

[0008] Conduct an environmental aging experiment on the fuse type temperature relay to be tested, and measure the contact resistance between the two lead terminals of the fuse type temperature relay and the insulation resistance between the lead terminals and the housing;

[0009] Judge whether the fuse type temperature relay deteriorates according to the contact resistance and the insulation resistance;

[0010] Determine the time required for the deteriorated and non-deteriorated fuse type temperature relays to deteriorate;

[0011] Calculate the conversion coefficient between the life under test conditions and the life under use conditions, and then obtain the service life of the fuse type temperature relay to be tested.

[0012] According to the second aspect of the embodiments of the present invention, a system for evaluating the reliability of a vehicle fuse type temperature relay is provided, including:

[0013] An environmental aging experiment module for conducting an environmental aging experiment on the fuse type temperature relay to be tested, and measuring the contact resistance between the two lead terminals of the fuse type temperature relay and the insulation resistance between the lead terminals and the housing;

[0014] A deterioration judgment module for judging whether the fuse type temperature relay deteriorates according to the contact resistance and the insulation resistance;

[0015] A deterioration time calculation module for determining the time required for the deteriorated and non-deteriorated fuse type temperature relays to deteriorate;

[0016] A life evaluation module for calculating the conversion coefficient between the life under test conditions and the life under use conditions, and then obtaining the service life of the fuse type temperature relay to be tested.

[0017] According to the third aspect of the embodiments of the present invention, a terminal device is provided, which includes a processor and a memory. The processor is used to implement each instruction; the memory is used to store multiple instructions, and the instructions are suitable for being loaded and executed by the processor to perform the above-mentioned method for evaluating the reliability of a vehicle fuse type temperature relay.

[0018] According to the fourth aspect of the embodiments of the present invention, a computer-readable storage medium is provided, in which multiple instructions are stored, and the instructions are suitable for being loaded and executed by the processor of the terminal device to perform the above-mentioned method for evaluating the reliability of a vehicle fuse type temperature relay.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] (1) Based on the deterioration time of the contact resistance and insulation resistance of the fuse-type temperature relay under three different aging environments, the present invention uses formulas to convert the performance deterioration time of the fuse-type temperature relay under the three different aging environments into the aging time of the fuse-type temperature relay under the actual working environment, and then combines the three converted aging times to respectively obtain the aging time range of the fuse-type temperature relay in the actual working environment.

[0021] (2) Compared with the results obtained by converting using a single aging environment test, the results obtained by the present invention using three aging tests are more accurate, solving the problem that the reliability evaluation results of the fuse-type temperature relay for high-speed trains are inaccurate both at home and abroad.

[0022] (3) Under three different aging experiments respectively, the present invention determines the conversion coefficients of the service life of the fuse-type temperature relay under experimental conditions and usage conditions, which can make the life prediction results more accurate and reliable, and realizes the prediction of the fuse-type temperature relay through experiments to ensure the normal operation of the vehicle.

[0023] Advantages of additional aspects of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. Brief Description of the Drawings

[0024] Figure 1 It is a flow chart of the method for evaluating the reliability of the vehicle-used fuse-type temperature relay in the embodiment of the present invention; Detailed Embodiments

[0025] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present application. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0026] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those clearly listed steps or units, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or devices.

[0027] Without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0028] Embodiment 1

[0029] In one or more embodiments, a reliability evaluation method for a vehicle-mounted fuse type temperature relay is disclosed. In combination with Figure 1 , the specific process is as follows:

[0030] S101: Conduct an environmental aging experiment on the fuse type temperature relay to be tested, and measure the contact resistance between the two lead terminals of the fuse type temperature relay and the insulation resistance between the lead terminal and the housing;

[0031] In this embodiment, first, the contact resistance and the insulation resistance are selected as the key characteristic parameters of the fuse type temperature relay; the magnitude of the contact resistance directly reflects the contact condition of the two contacts of the temperature fuse tube in the fuse type temperature relay, and the magnitude of the insulation resistance reflects the excellent insulation performance of the fuse type temperature relay.

[0032] Use an LRC tester to measure the contact resistance between the two lead terminals of the fuse type temperature relay, and use an insulation resistance tester to measure the insulation resistance between the lead terminal of the fuse type temperature relay and the housing. For the contact resistance, its magnitude is generally between 20 and 60 mΩ, while the insulation resistance is at the GΩ level under normal circumstances.

[0033] In this embodiment, the environmental aging test includes a salt spray aging test, a damp heat aging test, and an accelerated life test. Divide the fuse type temperature relay to be tested into three groups, place them in different test chambers, and conduct a salt spray aging test, a damp heat aging test, and an accelerated life test respectively.

[0034] Among them, the specific process of the salt spray aging test is as follows: Prepare a sodium chloride solution with a mass fraction of 5% and a pH value of 6.5 - 7.2, use a humidifier to make it as evenly distributed as possible in the entire test chamber, and keep the temperature in the test chamber at about 35°C for a 96-hour salt spray aging test.

[0035] The specific process of the damp heat aging test is as follows: Set the temperature in the test chamber to about 85°C and keep the humidity at about 85% RH for a 96-hour damp heat aging test.

[0036] The specific process of the accelerated life test is as follows:

[0037] First condition: Set the vertical acceleration of the fuse type temperature relay for the traction motor (stator end, drive end, non-drive end) to 5.4 m / s², the horizontal acceleration to 4.7 m / s², and the longitudinal acceleration to 2.5 m / s²;

[0038] Second condition: Set the vertical acceleration of the fuse type temperature relay for the axle box and gearbox to 38 m / s², the horizontal acceleration to 34 m / s², and the longitudinal acceleration to 17 m / s²;

[0039] Select five appropriate temperature points from -40°C to 5°C above the normal operating temperature of the testing equipment for 96-hour thermal aging.

[0040] After conducting environmental aging tests on the selected fuse-type temperature relay samples, measure the contact resistance and insulation resistance of each fuse-type temperature relay sample, and record the measured contact resistance and insulation resistance data.

[0041] S102: Determine whether the fuse-type temperature relay is deteriorated based on the contact resistance and insulation resistance;

[0042] Specifically, for the contact resistance between the two lead terminals of the fuse-type temperature relay, if it exceeds 100 mΩ, it indicates that it has deteriorated and no longer meets the requirements of the fuse-type temperature relay for high-speed trains regarding contact resistance. For the insulation resistance between the lead terminal and the housing, if its value is less than 500 MΩ, it indicates that it has deteriorated and no longer meets the requirements of the fuse-type temperature relay for high-speed trains regarding insulation resistance.

[0043] S103: Determine the time required for the deteriorated and non-deteriorated fuse-type temperature relays to deteriorate;

[0044] In this embodiment, for the non-deteriorated fuse-type temperature relays, combine the change law of their characteristic parameters in the test for fitting, predict their deterioration time, and then conduct reliability life assessment. For the deteriorated fuse-type temperature relays, the deterioration time can be directly obtained, and then reliability life assessment is carried out.

[0045] Specifically, conduct functional fitting analysis on the degradation data of the samples with parameter degradation but not deteriorated. The fitting formula is as follows:

[0046] y = α + βt

[0047] Where y is the characteristic parameter, α is the intercept, β is the slope, and t is the test time.

[0048] According to the fitted linear relationship, the deterioration time of the non-deteriorated fuse-type temperature relay under continued test conditions can be obtained, and then its total deterioration time T a ;

[0049] For the fuse-type temperature relays that have deteriorated after the test, the deterioration time T a can be directly obtained, that is, the time required for the fuse-type temperature relay to degrade to the deterioration critical value under the test conditions.

[0050] Then, check the fuse type temperature relay that has undergone the test, and analyze the reasons for the changes in contact resistance and insulation resistance, so that when there are higher life requirements for the components in the later stage, targeted optimization design can be carried out.

[0051] In this embodiment, the reason for the change in contact resistance is mainly analyzed by using the X-ray photographing method. Using X-ray imaging technology, photograph the temperature fuse tube of the fuse type temperature relay before and after the test, and observe the height of its thermal sensitive pill. The change in the height of the thermal sensitive pill is the reason for the change in the contact resistance of the fuse type temperature relay.

[0052] In this embodiment, the reason for the change in insulation resistance is mainly analyzed by using the observation method. Use a microscope to observe whether there are features such as paint peeling, cracks, and damage on the surface of the fuse type temperature relay before and after the test, as well as the area size of these features. These surface features have a direct impact on the insulation resistance of the fuse type temperature relay.

[0053] S104: Calculate the conversion coefficient between the life under test conditions and the life under use conditions, and then obtain the service life of the fuse type temperature relay to be measured.

[0054] The life T under test conditions a The conversion coefficient with the life T under use conditions is a, and its calculation formula is:

[0055] T = aT a

[0056] According to different types of aging experiments, the calculation process of the conversion coefficient a is as follows:

[0057] ① Under the salt spray aging test, the conversion coefficient a satisfies the following relationship:

[0058]

[0059] Among them, k b is the Boltzmann constant 8.617385×10-5 eV / K; Ea is the activation energy of the chemical reaction, that is, the activation energy, and the unit is eV; u is the position model parameter; ω u 、ω a are the relative NaCl concentrations under the use environment and the salt spray aging test respectively; t u 、t a are the absolute temperatures under the use environment and the salt spray aging test respectively, and the unit is K; H u 、H a are the relative humidities under the use environment and the salt spray aging test respectively, and the unit is %.

[0060] ② Under the constant temperature and humidity aging test, the conversion coefficient a satisfies the following relationship:

[0061]

[0062] where k b is the Boltzmann constant 8.617385×10-5 eV / K; Ea is the activation energy of the chemical reaction, that is, the activation energy, with the unit of eV; u is the position model parameter; H u and H a are the relative humidity under the use environment and under the damp heat aging test at a constant temperature, respectively, with the unit of %. t u and t a are the absolute temperature under the use environment and under the damp heat aging test at a constant temperature, respectively, with the unit of K.

[0063] ③ Under the accelerated life test, the conversion factor a satisfies the following relationship:

[0064]

[0065] where Δt 1 is the temperature difference under the first condition; Δt 2 is the temperature difference under the second condition; m is the model constant, m = 6.96.

[0066] After calculating the conversion factors under different aging realizations, the life T a under the experimental conditions can be used to obtain the life T under the use conditions.

[0067] Example 2

[0068] In one or more embodiments, a reliability evaluation system for a vehicle-use fuse type temperature relay is disclosed, including:

[0069] An environmental aging experiment module for performing an environmental aging experiment on the fuse type temperature relay to be tested, and measuring the contact resistance between the two lead terminals of the fuse type temperature relay and the insulation resistance between the lead terminals and the housing;

[0070] A deterioration judgment module for judging whether the fuse type temperature relay deteriorates according to the contact resistance and the insulation resistance;

[0071] A deterioration time calculation module for determining the time required for the fuse type temperature relay that has deteriorated and the one that has not deteriorated to reach deterioration;

[0072] A life evaluation module for determining the conversion factor between the life under the test conditions and the life under the use conditions, and further obtaining the service life of the fuse type temperature relay to be tested.

[0073] It should be noted that the specific implementation processes of the above modules have been described in detail in Example 1, and will not be elaborated here.

[0074] Embodiment 3

[0075] In one or more embodiments, a terminal device is disclosed, including a server. The server includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it implements the reliability evaluation method of the vehicle-mounted fuse type temperature relay in Embodiment 1. For the sake of brevity, it will not be elaborated here.

[0076] It should be understood that in this embodiment, the processor may be a central processing unit CPU, and the processor may also be other general-purpose processors, digital signal processors DSP, application-specific integrated circuits ASIC, off-the-shelf programmable gate arrays FPGA, or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0077] The memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A part of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0078] In the implementation process, each step of the above method may be completed by the integrated logic circuit in the hardware of the processor or the instructions in the form of software.

[0079] In some other embodiments, a computer-readable storage medium is disclosed, in which multiple instructions are stored. The instructions are adapted to be loaded and executed by the processor of the terminal device to implement the reliability evaluation method of the vehicle-mounted fuse type temperature relay described in Embodiment 1.

[0080] Those skilled in the art should understand that the embodiments of the present application may be provided as a method, a system, or a computer program product. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0081] 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 flowcharts and / or block diagrams, and combinations of flows and / or blocks in the flowcharts and / or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to the processors of general-purpose computers, special-purpose computers, embedded processors, or other programmable data processing devices to produce a machine, such that the instructions executed by the processors of the computer or other programmable data processing devices generate means for implementing the functions specified in the Figure 1 one or more flows and / or blocks Figure 1 one or more blocks.

[0082] 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 produce a manufactured article including instruction means that implement the functions specified in the Figure 1 one or more flows and / or blocks Figure 1 one or more blocks.

[0083] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in the Figure 1 one or more flows and / or blocks Figure 1 one or more blocks.

[0084] 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 it is still possible to modify the specific implementation manners of the present invention or make equivalent replacements. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention shall be covered by the protection scope of the claims of the present invention.

Claims

1. A reliability evaluation method for a vehicle - used fusing temperature relay, characterized in that, it includes: Conduct an environmental aging experiment on the fusing temperature relay to be tested, and measure the contact resistance between the two lead terminals of the fusing temperature relay and the insulation resistance between the lead terminals and the housing; The conducting of the environmental aging experiment on the fusing temperature relay to be tested specifically includes: Divide the samples of the fusing temperature relay to be tested into three groups, place them in different experimental chambers, and conduct salt - spray aging test, damp - heat aging test and accelerated life test respectively; Judge whether the fusing temperature relay deteriorates according to the contact resistance and insulation resistance; Determine the time required for the deteriorated and non - deteriorated fusing temperature relays to deteriorate; calculate the conversion coefficient between the life under test conditions and the life under use conditions, and then obtain the service life of the fusing temperature relay to be tested. Specifically: The conversion coefficients under the salt - spray aging test are determined respectively according to the absolute temperature, relative NaCl concentration and relative humidity in the use environment and the salt - spray aging test environment; The conversion coefficients under the damp - heat aging test are determined respectively according to the absolute temperature and relative humidity in the use environment and the damp - heat aging test environment; The conversion coefficients under the accelerated life test are determined respectively according to the temperature difference under the first condition and the temperature difference under the second condition.

2. The reliability evaluation method for a vehicle - used fusing temperature relay according to claim 1, characterized in that, The judging whether the fusing temperature relay deteriorates according to the contact resistance and insulation resistance specifically is: Measure the contact resistance and insulation resistance of each sample of the fusing temperature relay. When the magnitude of the contact resistance or insulation resistance exceeds the set threshold value, it is determined that the fusing temperature relay has deteriorated; otherwise, it has not deteriorated.

3. The reliability evaluation method for a vehicle - used fusing temperature relay according to claim 1 or 2, characterized in that, After conducting the environmental aging experiment on the fusing temperature relay to be tested, it further includes: Using X - ray imaging technology, photograph the temperature fuse tube of the fusing temperature relay before and after the test, and observe the height of its thermal - sensitive pill. The change in the height of the thermal - sensitive pill is the reason for the change in the contact resistance of the fusing temperature relay.

4. The reliability evaluation method for a vehicle - used fusing temperature relay according to claim 1 or 2, characterized in that, After conducting the environmental aging experiment on the fusing temperature relay to be tested, it further includes: Observe whether there are features such as paint peeling, cracks or damage on the surface of the fusing temperature relay before and after the test, and the area size of these features; the above - mentioned features on the surface of the fusing temperature relay are the reasons for the change in the insulation resistance.

5. The reliability evaluation method for a vehicle - used fusing temperature relay according to claim 1, characterized in that, Determining the time required for the deteriorated and non - deteriorated fusing temperature relays to deteriorate specifically includes: For the deteriorated fusing temperature relay, the time required for the fusing temperature relay to degrade to the deterioration critical value under the test conditions is the time required for the fusing temperature relay to deteriorate; For a non-degraded fuse type temperature relay, the degradation data of the fuse type temperature relay is fitted to obtain the time required for the non-degraded fuse type temperature relay to degrade under continued experimental conditions, and then the total degradation time is obtained.

6. A reliability evaluation system for a vehicle fuse type temperature relay, characterized in that, it includes: An environmental aging experiment module for performing an environmental aging experiment on the fuse type temperature relay to be tested, and measuring the contact resistance between the two lead terminals of the fuse type temperature relay and the insulation resistance between the lead terminals and the housing; The performing an environmental aging experiment on the fuse type temperature relay to be tested specifically includes: Dividing the samples of the fuse type temperature relay to be tested into three groups, placing them in different experimental chambers, and respectively performing a salt spray aging test, a damp heat aging test, and an accelerated life test; A degradation judgment module for judging whether the fuse type temperature relay is degraded according to the contact resistance and the insulation resistance; A degradation time calculation module for determining the time required for the degraded and non-degraded fuse type temperature relays to reach degradation; A life evaluation module for calculating the conversion coefficient between the life under test conditions and the life under use conditions, and then obtaining the service life of the fuse type temperature relay to be tested, specifically: The conversion coefficients under the salt spray aging test are determined respectively according to the absolute temperature, relative NaCl concentration, and relative humidity in the use environment and the salt spray aging test environment; The conversion coefficients under the damp heat aging test are determined respectively according to the absolute temperature and relative humidity in the use environment and the damp heat aging test environment; The conversion coefficients under the accelerated life test are determined respectively according to the temperature difference under the first condition and the temperature difference under the second condition.

7. A terminal device, which includes a processor and a memory, the processor is used to implement each instruction; the memory is used to store multiple instructions, characterized in that, the instructions are suitable for being loaded and executed by the processor to perform the reliability evaluation method for the vehicle fuse type temperature relay according to any one of claims 1-5.

8. A computer-readable storage medium, in which multiple instructions are stored, characterized in that, the instructions are suitable for being loaded and executed by the processor of the terminal device to perform the reliability evaluation method for the vehicle fuse type temperature relay according to any one of claims 1-5.

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