A multi-channel high and low temperature test system and method for inductive sensors

Abstract

The present application discloses a multi-channel high and low temperature test system and method for an inductive sensor, which relates to the field of sensor testing technology, and solves the technical problem that the existing high and low temperature test method does not consider the influence of the test temperature on the component, resulting in a low accuracy rate of the test result. The system and method include: a data acquisition module: acquiring the test data of each inductive sensor in real time through a data acquisition device; a test planning module: acquiring the characteristic data of the inductive sensor through an interactive module, generating a plurality of temperature test points according to the characteristic data; generating a temperature adjustment direction according to the temperature test points; a test module: generating a temperature adjustment signal according to the test data; performing temperature control on the temperature adjustment module according to the temperature adjustment signal; generating a test result according to the test value of each temperature test point; and generating test schemes for different sensors in a targeted manner according to the characteristic data of the sensor, so that the test result of the sensor is more accurate.

Description

Technical Field

[0001] The present application belongs to the field of sensor testing technology, and relates to sensor testing technology, and specifically to a multi-channel high and low temperature testing system and method for an inductive sensor. Background Art

[0002] An inductive sensor is a sensor that works based on the principle of electromagnetic induction. It uses changes in the self-inductance or mutual inductance of a coil to achieve measurement. It is widely used in industrial automation, robotics, automotive, medical, aerospace, biomedical and other fields. With the development of wireless communication technology, inductive sensors will also realize remote measurement and monitoring functions, making greater contributions to the progress of human society.

[0003] The prior art (the invention patent application with publication number CN114166107A) discloses a high and low temperature performance test device for a multi-channel proximity sensor mechanism, including a high and low temperature box, a linear motion mechanism, and a mounting turntable. The mounting turntable includes a rotation mechanism and a bearing frame. The rotation mechanism drives the bearing frame to rotate. The bearing frame is provided with a plurality of bearing seats along the circumference. The bearing seats are provided with a plurality of test stations for bearing proximity sensor mechanisms in sequence from top to bottom. The interior of the high and low temperature box is provided with a mounting turntable. The exterior of the high and low temperature box is provided with a plurality of linear motion mechanisms in sequence from top to bottom. The driving end of the linear motion mechanism extends into the interior of the high and low temperature box and is connected to the target provided at the corresponding test station. The multi-channel sensor test is realized by the above-mentioned equipment, which greatly improves the test efficiency.

[0004] The prior art (an invention patent with announcement number CN112595921B) discloses a high and low temperature testing method for electronic components, including the following steps: S1, start the main controller to prepare for the electronic component test; S2, the main controller controls the transport arm to move at least one electronic component from the carrier plate to the conveyor and rotate to adjust the angle; S3, the main controller controls the temperature control module 1 to drive the test arm to suck and press at least one electronic component to the test bench; S4, the main controller controls the external temperature control mechanism to heat up or cool the electronic component to complete the test of the electronic component at a specific temperature; S5, after the test is completed, the main controller controls the temperature control module to drive the test arm to suck and press at least one electronic component to be transported back to the carrier plate by the conveyor.

[0005] The above-mentioned high and low temperature test method performs high and low temperature tests on the same electronic component; obtains the performance data of the component at different specific temperatures; and because different components have different tolerance and sensitivity to temperature, during the test process, the temperature is simply adjusted to reach the desired test temperature. When continuous temperature testing is performed, the previous test temperature may have a greater impact on the component, resulting in a lower accuracy rate of subsequent test results, thereby affecting the efficiency of the entire component test; therefore, a multi-channel high and low temperature test system and method for an inductive sensor is needed. Summary of the invention

[0006] The present application aims to solve at least one of the technical problems existing in the prior art; to this end, the present application proposes a multi-channel high and low temperature testing system and method for an inductive sensor, which is used to solve the technical problem that the existing high and low temperature testing method does not consider the influence of the test temperature on the component, resulting in low accuracy of the test results. The present application sets a number of temperature test points according to the characteristics of the inductive sensor, and sets the temperature test direction according to the characteristics of the sensor, and determines whether retesting is needed according to the test results, thereby greatly improving the accuracy of the test results; the above-mentioned problems are solved.

[0007] To achieve the above-mentioned object, the first aspect of the present application provides a multi-channel high and low temperature test system for an inductive sensor, comprising: a data acquisition module, a test planning module, a test module, a temperature adjustment module and an interaction module;

[0008] The data acquisition module: acquires the test data of each inductive sensor in real time through the data acquisition device;

[0009] The test planning module: obtains characteristic data of the inductive sensor through the interactive module, generates a number of temperature test points according to the characteristic data; generates a temperature adjustment direction according to the temperature test points;

[0010] The test module: generates a temperature adjustment signal according to the test data; performs temperature control on the temperature adjustment module according to the temperature adjustment signal; and obtains the test value of each temperature test point corresponding to each test item, and generates a test result according to the test value of each temperature test point; the test result includes a test data packet and a test signal, and the test signal includes a test completion signal or a third temperature direction retest signal.

[0011] The present application generates several temperature test points through the characteristic data of the inductive sensor; generates a temperature adjustment direction according to the temperature test points and the sensor characteristic data, and performs temperature testing on the inductive sensor according to the temperature adjustment direction; during the test process, a temperature adjustment signal is generated according to the test data to adjust the test temperature, and a test result is generated according to the test value; and test schemes for different sensors are generated in a targeted manner according to the characteristic data of the sensor, so that the test scheme is more matched with the corresponding sensor, thereby making the test result of the sensor more accurate.

[0012] Preferably, generating a plurality of temperature test points according to the characteristic data includes:

[0013] Obtain the temperature adjustment range of the test equipment and divide the temperature adjustment range into several temperature intervals;

[0014] Extract the inductor type and inductor material from the characteristic data; search for the corresponding temperature characteristic curve L(T) in the temperature characteristic curve lookup table according to the inductor type and inductor material;

[0015] By formula Get the distribution coefficient FP of the temperature interval numbered i i ; Among them, T i is the lower limit temperature value of the temperature interval numbered i; BXY is the set slope threshold;

[0016] By formula Calculate the number of test points corresponding to the temperature interval numbered i, where: is the rounding symbol; CSi is the number of test points corresponding to the temperature test point in the temperature interval numbered i; α is the adjustment coefficient, 0<α<1; BS is the number of standard test points;

[0017] Evenly set the number of test points within the corresponding temperature range.

[0018] Preferably, the temperature characteristic curve lookup table is established by the following steps:

[0019] Step 1: Obtain several inductors with the same inductor type and inductor material;

[0020] Step 2: Adjust the test temperature from low to high in sequence to obtain the inductive reactance value of each inductor;

[0021] Step 3: Take the average value of the inductive reactance values ​​corresponding to each inductor as the inductive reactance value at the corresponding test temperature;

[0022] Step 4: Use the inductive reactance value at each test temperature as the ordinate and the test temperature as the abscissa to fit the temperature characteristic curve corresponding to the inductor standard and inductor material. The fitting method can be the interpolation method.

[0023] Step 5: Obtain temperature characteristic curves corresponding to several inductors of different inductor types and inductor materials;

[0024] Step 6: Construct a temperature characteristic curve lookup table based on the one-to-one correspondence between the inductor type and the inductor material and the temperature characteristic curve.

[0025] Preferably, generating the temperature adjustment direction according to the temperature test point includes:

[0026] The temperature test point with the highest temperature value is marked as the high temperature test point; the temperature test point with the lowest temperature value is marked as the low temperature test point;

[0027] Obtaining an inductance value 1 of the temperature characteristic curve corresponding to the high temperature test point; and an inductance value 2 of the temperature characteristic curve corresponding to the low temperature test point;

[0028] Obtain the inductance value three of the temperature curve corresponding to the initial temperature test point; determine whether the difference between the inductance value one and the inductance value three is less than the difference between the inductance value two and the inductance value three;

[0029] If yes, then the direction from the initial temperature test point to the high temperature test point is taken as the first temperature test direction, the direction from the high temperature test point to the initial temperature test point is taken as the second temperature test direction, and the direction from the initial temperature test point to the low temperature test point is taken as the third temperature test direction; the first temperature test direction, the second temperature test direction and the third temperature test direction are sequentially integrated into the temperature adjustment direction;

[0030] No, then the first temperature test direction is from the initial temperature test point to the low temperature test point, the second temperature test direction is from the low temperature test point to the initial temperature test point, and the third temperature test direction is from the initial temperature test point to the high temperature test point; the first temperature test direction, the second temperature test direction and the third temperature test direction are sequentially integrated into the temperature adjustment direction.

[0031] Preferably, the initial temperature test point is a temperature test point in the temperature characteristic curve corresponding to each temperature test point where the inductance value is closest to the inductance calibration value.

[0032] Preferably, generating a temperature adjustment signal according to the test data includes:

[0033] Obtain the test data corresponding to the current test cycle at the temperature test point; extract the item time change curve corresponding to each test item in the test data; determine whether all item time change curves are stable;

[0034] If yes, the detection value corresponding to the stabilized test item is marked as the test value corresponding to each test item at the corresponding temperature test point; a positive temperature adjustment signal is generated;

[0035] If not, when the accumulated time of the test cycle is greater than the set time threshold, determine whether the temperature adjustment direction is the first temperature adjustment direction; if yes, generate a reverse temperature adjustment signal; if not, generate a stop adjustment signal; otherwise, after the next test cycle is over, obtain and determine whether the time change curves of all items corresponding to the next test cycle are stable;

[0036] The temperature adjustment signal includes a forward temperature adjustment signal, a reverse temperature adjustment signal and a stop adjustment signal.

[0037] Preferably, the determining whether the time variation curves of all items are stable includes:

[0038] Obtain the time change curve of each project;

[0039] Divide the project time change curve into several time period curves according to the acceptable stable duration, obtain the variance of the last time period curve, and determine whether the variance is less than the set variance threshold. If yes, mark the project time change curve as a stable state; if no, mark the project time change curve as an unstable state;

[0040] When all project time variation curves are in a stable state, then all project time variation curves are stable; otherwise, all project time variation curves are unstable.

[0041] Preferably, the temperature control according to the temperature adjustment signal includes:

[0042] When the temperature adjustment signal is a stop adjustment signal, the temperature adjustment module of the control test setting stops running;

[0043] When the temperature adjustment signal is a positive temperature adjustment signal, the current temperature adjustment direction is obtained; and the temperature adjustment module is controlled to enter the next temperature test point according to the direction of the current temperature adjustment direction;

[0044] When the temperature adjustment signal is a reverse temperature adjustment signal, it jumps to the next temperature adjustment direction; and controls the temperature adjustment module to enter the next temperature test point according to the temperature adjustment direction.

[0045] Preferably, generating the test results according to the test values ​​of each temperature test point includes:

[0046] Obtain the difference between the test values ​​of each same temperature test point in the first temperature test direction and the second temperature test direction for the same test item;

[0047] Determine whether the difference of each temperature test point is less than the difference threshold;

[0048] If yes, when the difference between the test values ​​of the initial temperature test points in the first temperature test direction and the second temperature test direction is less than the difference threshold, the test values ​​of each temperature test point in the first temperature test direction are used as the final test values ​​of the corresponding temperature test points; and the test values ​​of each temperature test point in the third temperature direction are also set as the final test values; the final test values ​​of each temperature test point are fitted into a project temperature characteristic curve of the corresponding test item in the order of the temperature test points from low to high; the project temperature characteristic curves of each test item of multiple inductive sensors and the project time change curves of each item corresponding to each temperature test point are packaged to generate a test data packet, and a test completion signal is generated;

[0049] If not, the test values ​​of each temperature test point in the first temperature test direction are used as the final test values ​​of the corresponding temperature test points, and the final test values ​​of each temperature test point in the first temperature test direction are fitted into partial temperature characteristic curves of the corresponding test items in the order of the temperature test points from low to high; the partial temperature characteristic curves of each test item of multiple inductive sensors and the project time change curves of each item corresponding to each temperature test point are packaged to generate a test data packet, and a re-test signal in the third temperature direction is generated.

[0050] The present application determines whether the test values ​​of each temperature test point are accurate through the difference in test values ​​corresponding to each same temperature test point in the first temperature test direction and the second temperature test direction, and generates a test result based on the judgment result; thus making the final test result more accurate, thereby improving the efficiency of the entire inductive sensor test.

[0051] On the other hand, the present application provides a multi-channel high and low temperature testing method for an inductive sensor, comprising the following steps:

[0052] Step 1: Obtain characteristic data of the inductive sensor;

[0053] Step 2: generating a number of temperature test points according to the characteristic data;

[0054] Step 3: generating a temperature test direction according to the temperature test point; the temperature test direction includes a first temperature test direction, a second temperature test direction and a third temperature test direction;

[0055] Step 4: Generate a temperature adjustment signal according to the test data; and perform temperature control on the temperature adjustment module according to the temperature adjustment signal;

[0056] Step 5: Obtain the test values ​​of each test item corresponding to each temperature test point; generate test results according to the test values ​​of each temperature test point.

[0057] Compared with the prior art, the beneficial effects of this application are:

[0058] 1. The present application generates several temperature test points through the characteristic data of the inductive sensor; generates a temperature adjustment direction according to the temperature test points and the sensor characteristic data, and performs temperature testing on the inductive sensor according to the temperature adjustment direction; during the test process, generates a temperature adjustment signal according to the test data to adjust the test temperature, and generates a test result according to the test value; generates test schemes for different sensors according to the characteristic data of the sensor, so that the test scheme is more matched with the corresponding sensor, thereby making the test result of the sensor more accurate.

[0059] 2. The present application determines whether the test values ​​of each temperature test point are accurate through the difference in test values ​​corresponding to each same temperature test point in the first temperature test direction and the second temperature test direction, and generates a test result based on the judgment result; thus making the final test result more accurate, thereby improving the efficiency of the entire inductive sensor test. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0061] Figure 1 This is a schematic diagram of the principle of the multi-channel high and low temperature testing system in this application;

[0062] Figure 2 Schematic diagram of the steps of the multi-channel high and low temperature testing method in this application. DETAILED DESCRIPTION

[0063] The technical solution of the present application will be described clearly and completely below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0064] See also Figure 1 , a first aspect of the present application provides a multi-channel high and low temperature test system for an inductive sensor, comprising: a data acquisition module, a test planning module, a test module, a temperature adjustment module and an interaction module;

[0065] Data acquisition module: the test data of each inductive sensor is acquired in real time through the data acquisition device; the test data is the collected data of each test item of the inductive sensor, including the project time variation curve of each test item; the project time variation curve is the variation curve of the detection value corresponding to each test item with the test time; the test items include one or more of current, voltage, power, resistance and reactance, etc.;

[0066] Test planning module: obtains characteristic data of inductive sensors through interactive modules. The characteristic data is the characteristics of the inductance in the inductive sensors, including inductance type and inductance material, etc. Inductance types include winding type, multilayer type and stamping type, etc. Inductance materials include core materials and winding materials, etc. Core materials include nickel-zinc ferrite, manganese-zinc ferrite, ceramics and glass, etc. Generates several temperature test points based on characteristic data. The temperature test points are the temperature points that need to be tested for the corresponding inductive sensors. Generates temperature adjustment directions based on temperature test points. The temperature test direction is the temperature adjustment direction during the test, such as adjusting from 35 degrees to 80 degrees, etc.

[0067] Test module: Generate a temperature adjustment signal according to the test data; the temperature adjustment signal is used to control the temperature of the temperature adjustment module to adjust it from the current temperature test point to the next temperature test point according to the temperature adjustment direction; perform temperature control on the temperature adjustment module according to the temperature adjustment signal; and obtain the test value of each test item corresponding to each temperature test point, the test value is the stable detection value of the corresponding detection value at the corresponding temperature test point; generate a test result according to the test value of each temperature test point; the test result includes a test data packet and a test signal, the test signal includes a test completion signal or a third temperature direction re-test signal, the third temperature direction re-test signal indicates that a batch of inductive sensors needs to be replaced to re-test the third temperature direction.

[0068] This embodiment generates several temperature test points through the characteristic data of the inductive sensor; generates a temperature adjustment direction according to the temperature test points and the sensor characteristic data, and performs temperature testing on the inductive sensor according to the temperature adjustment direction; during the test, generates a temperature adjustment signal according to the test data to adjust the test temperature, and generates a test result according to the test value; and generates test schemes for different sensors according to the characteristic data of the sensor, so that the test scheme is more matched with the corresponding sensor, thereby making the test result of the sensor more accurate.

[0069] Generating a number of temperature test points according to the characteristic data includes: obtaining a temperature adjustment range of the test device, and equally dividing the temperature adjustment range into a number of temperature intervals; the equal division here is divided according to experience, and the temperature adjustment range in this embodiment is -40 degrees to 180 degrees; every 10 degrees is divided into a temperature interval, and there are 22 temperature intervals;

[0070] Extract the inductance type and inductance material in the characteristic data; it can be understood that the inductance sensor in this embodiment includes only one inductance, or includes multiple inductances with similar inductance types and inductance materials; according to the inductance type and inductance material, find the corresponding temperature characteristic curve L(T) in the temperature characteristic curve lookup table;

[0071] By formula Get the distribution coefficient FP of the temperature interval numbered i i ; Among them, T i is the lower limit temperature value of the temperature interval numbered i. Since the temperature intervals are continuous, the lower limit temperature value of the temperature interval numbered i+1 can represent the upper limit temperature value of the temperature interval numbered i. BXY is the set slope threshold;

[0072] This embodiment calculates the influence of temperature on the inductance of the inductive sensor in each temperature range through the above formula. The greater the influence of temperature, the greater the corresponding distribution coefficient, and the more detailed the test in the corresponding temperature range. The distribution coefficient can be understood as the average change rate of inductance with temperature in each temperature range. The greater the average change rate, the greater the corresponding distribution coefficient. The slope threshold can be understood as an adjustment coefficient, which is used to adjust the difference in distribution coefficients between different temperature ranges.

[0073] By formula Calculate the number of test points corresponding to the temperature interval numbered i, where: is the rounding symbol; CSi is the number of test points corresponding to the temperature test point in the temperature interval numbered i; α is the adjustment coefficient, 0<α<1, BS is the number of standard test points; the number of standard test points is set artificially; the number of test points is evenly set in the corresponding temperature interval.

[0074] In this embodiment, a number of temperature test points are set in each interval through the above method. When the inductance is greatly affected by temperature in the temperature interval, the number of temperature test points set in the corresponding temperature interval is large. When the inductance is less affected by temperature in the temperature interval, the number of temperature test points set in the corresponding temperature interval is small. According to the characteristics of the inductive sensor, the temperature test points are set in each temperature interval in a targeted manner, so that the final test results can better reflect the characteristics of the corresponding inductive sensor.

[0075] The temperature characteristic curve lookup table is established by the following steps:

[0076] Step 1: Obtain several inductors with the same inductor type and inductor material;

[0077] Step 2: Adjust the test temperature from low to high in sequence, and obtain the inductive reactance value of each inductor respectively; it is understandable that when adjusting the test temperature, when the amplitude of the measured inductive reactance value changes slightly, the temperature adjustment is performed again; in other embodiments, other suitable inductor characteristics may be used to replace the inductive reactance value, such as quality factor, etc.;

[0078] Step 3: Take the average value of the inductive reactance values ​​corresponding to each inductor as the inductive reactance value at the corresponding test temperature;

[0079] Step 4: Use the inductive reactance value at each test temperature as the ordinate and the test temperature as the abscissa to fit the temperature characteristic curve corresponding to the inductor standard and inductor material. The fitting method can be the interpolation method.

[0080] Step 5: Obtain temperature characteristic curves corresponding to several inductors of different inductor types and inductor materials;

[0081] Step 6: Construct a temperature characteristic curve lookup table based on the one-to-one correspondence between the inductor type and the inductor material and the temperature characteristic curve.

[0082] Generating a temperature adjustment direction according to the temperature test points, including: marking the temperature test point with the highest temperature value as a high temperature test point; marking the temperature test point with the lowest temperature value as a low temperature test point;

[0083] Obtaining an inductance value 1 of the temperature characteristic curve corresponding to the high temperature test point; and an inductance value 2 of the temperature characteristic curve corresponding to the low temperature test point;

[0084] Obtain the inductance value three of the temperature curve corresponding to the initial temperature test point; the initial temperature test point is the temperature test point whose inductance value is closest to the inductance calibration value in the temperature characteristic curve corresponding to each temperature test point;

[0085] Determine whether the difference between the inductance value 1 and the inductance value 3 is less than the difference between the inductance value 2 and the inductance value 3;

[0086] If yes, then the direction from the initial temperature test point to the high temperature test point is taken as the first temperature test direction, the direction from the high temperature test point to the initial temperature test point is taken as the second temperature test direction, and the direction from the initial temperature test point to the low temperature test point is taken as the third temperature test direction; the first temperature test direction, the second temperature test direction and the third temperature test direction are sequentially integrated into the temperature adjustment direction;

[0087] No, then the first temperature test direction is from the initial temperature test point to the low temperature test point, the second temperature test direction is from the low temperature test point to the initial temperature test point, and the third temperature test direction is from the initial temperature test point to the high temperature test point; the first temperature test direction, the second temperature test direction and the third temperature test direction are sequentially integrated into the temperature adjustment direction.

[0088] This embodiment sets the temperature test direction according to the characteristics of the inductive sensor and performs continuous temperature tests. When the low temperature has little effect on the inductive sensor, the low temperature is tested first to prevent the inductive sensor from being seriously or irreversibly affected by the lowest temperature or the highest temperature when the inductive sensor is tested at the lowest temperature or the highest temperature, so that the test results are inaccurate in subsequent tests. At the same time, this embodiment sets the first temperature test direction and the second temperature test direction as two opposite test processes, and the corresponding temperature test points are the same. Therefore, the test results of the first temperature test direction can be used to verify the test results of the second temperature test direction, so as to timely detect whether the low temperature or high temperature has an effect on the inductive sensor, and further ensure the accuracy of the test results.

[0089] Generate a temperature adjustment signal according to the test data, including: obtaining the test data corresponding to the current test cycle at the temperature test point; extracting the project time change curve corresponding to each test item in the test data; the project time change curve is the curve of the detection value of the corresponding test item in the corresponding test cycle changing with time; the detection value is the measured value of the corresponding test item at each time point in the test cycle; determine whether all the project time change curves are stable;

[0090] If yes, the detection value corresponding to the stabilized test item is marked as the test value corresponding to each test item at the corresponding temperature test point; the test value is the stable detection value of the corresponding detection value at the corresponding temperature test point; a positive temperature adjustment signal is generated; the positive temperature adjustment signal is to adjust the temperature according to the original temperature adjustment direction;

[0091] If not, when the accumulated time of the test cycle is greater than the set time threshold, determine whether the temperature adjustment direction is the first temperature adjustment direction; if yes, generate a reverse temperature adjustment signal; the reverse temperature adjustment signal is to adjust in the opposite direction of the original temperature adjustment direction; if not, generate a stop adjustment signal; the stop signal is to stop the temperature adjustment, and directly generate the test results from the test values ​​of each measured temperature test point; if the stop adjustment signal is generated, it means that the inductive sensor has been greatly affected by the temperature, and the accuracy of the results obtained in subsequent tests is low, and the sensor needs to be replaced and retested; otherwise, after the next test cycle is over, obtain and determine whether the time change curves of all items corresponding to the next test cycle are stable;

[0092] The temperature adjustment signal includes a forward temperature adjustment signal, a reverse temperature adjustment signal and a stop adjustment signal.

[0093] It is worth noting that in another embodiment, when the temperature test is performed in the second temperature test direction, after the test of each temperature test point is completed, the test value of the corresponding temperature test point is compared with the test value of the corresponding temperature test point in the first temperature test direction. When the difference exceeds the difference threshold, the corresponding temperature test point is marked. At the end of the test in the second temperature test direction, it is determined whether the number of marked temperature test points is the same as the number of temperature test points actually tested in the second temperature test direction. If they are the same, a stop adjustment signal is directly generated; if they are not the same, it is determined whether the initial temperature test point is marked. If yes, a stop adjustment signal is directly generated; if not, no operation is performed;

[0094] Determine whether the time change curves of all projects are stable, including: obtaining the time change curves of each project;

[0095] The project time change curve is divided into several time period curves according to the acceptable stable duration. The acceptable stable duration is the shortest stable duration of the test curve. The stability exceeding this duration is considered stable. The variance of the last time period curve is obtained to determine whether the variance is less than the set variance threshold. If yes, the project time change curve is marked as a stable state; if not, the project time change curve is marked as an unstable state. It can be understood that determining whether the variance is less than the set variance threshold is mainly to determine whether the project time change curve corresponding to each test cycle is stable within the last acceptable stable duration.

[0096] When all project time variation curves are in a stable state, then all project time variation curves are stable; otherwise, all project time variation curves are unstable.

[0097] Performing temperature control according to the temperature control signal includes: when the temperature control signal is a stop control signal, controlling the temperature control module set in the test to stop running;

[0098] When the temperature adjustment signal is a positive temperature adjustment signal, the current temperature adjustment direction is obtained; and the temperature adjustment module is controlled to enter the next temperature test point according to the direction of the current temperature adjustment direction;

[0099] When the temperature adjustment signal is a reverse temperature adjustment signal, it jumps to the next temperature adjustment direction, that is, the second temperature test direction; and controls the temperature adjustment module to enter the next temperature test point according to the temperature adjustment direction.

[0100] Specifically, in this embodiment, 22 temperature intervals are set from -40 degrees to 180 degrees, and a number of temperature test points are set in each test interval; and the first temperature test direction is 25 degrees to -40 degrees, the second temperature test direction is -40 degrees to 25 degrees, and the third temperature test direction is 25 degrees to 180 degrees; at the temperature test point corresponding to -30 degrees in the first temperature test direction, if the generated temperature adjustment signal is a stop test signal, the operation of the temperature adjustment module is stopped, and the test results are generated and output according to the test values ​​of each measured temperature test point; replace the inductive sensor, and perform the third temperature test direction test Test; at the temperature test point corresponding to -30 degrees in the first temperature test direction, if the temperature adjustment signal generated is a forward temperature adjustment signal, it is adjusted in the direction of 25 degrees to -40 degrees to the next temperature test point for testing. The next temperature test point in this embodiment is -30.5 degrees; at the temperature test point corresponding to -30 degrees in the first temperature test direction, if the temperature adjustment signal generated is a reverse temperature adjustment signal, it is adjusted in the second temperature adjustment direction, i.e., -40 degrees to 25 degrees, to the next temperature test point of -30 degrees for testing. The next temperature test point in this embodiment is -29 degrees.

[0101] Generating a test result according to the test values ​​of each temperature test point, including: obtaining the difference between the test values ​​of each same temperature test point in the first temperature test direction and the second temperature test direction of the same test item;

[0102] Determine whether the difference of each temperature test point is less than the difference threshold;

[0103] If yes, when the difference between the test values ​​of the initial temperature test points in the first temperature test direction and the second temperature test direction is less than the difference threshold, the test values ​​of each temperature test point in the first temperature test direction are used as the final test values ​​of the corresponding temperature test points; and the test values ​​of each temperature test point in the third temperature direction are also set as the final test values; the final test values ​​of each temperature test point are fitted into a project temperature characteristic curve of the corresponding test item in the order of the temperature test points from low to high; the project temperature characteristic curves of each test item of multiple inductive sensors and the project time change curves of each item corresponding to each temperature test point are packaged to generate a test data packet, and a test completion signal is generated;

[0104] If not, the test values ​​of each temperature test point in the first temperature test direction are used as the final test values ​​of the corresponding temperature test points, and the final test values ​​of each temperature test point in the first temperature test direction are fitted into partial temperature characteristic curves of the corresponding test items in the order of the temperature test points from low to high; the partial temperature characteristic curves of each test item of multiple inductive sensors and the project time change curves of each item corresponding to each temperature test point are packaged to generate a test data packet, and a re-test signal in the third temperature direction is generated.

[0105] When the difference between the test values ​​corresponding to the same temperature test points in the first temperature test direction and the second temperature test direction is within an acceptable range, it means that the temperature test points in the first temperature test direction have no effect or little effect on the inductive sensor, and the performance of the inductive sensor is almost the same as before the test; at this time, the test values ​​obtained at the temperature test points in the third temperature test direction are relatively accurate.

[0106] When the difference between the test values ​​of the initial temperature test point in the first temperature test direction and the second temperature test direction is less than the difference threshold, and the difference between the test values ​​of other temperature test points may be greater than the difference threshold, it means that a temperature test point in the first temperature test direction has caused a reversible impact on the inductive sensor; when returning to the initial temperature test point, the impact is already within an acceptable range, and the performance of the inductive sensor is almost the same as before the test; at this time, the test values ​​obtained at each temperature test point in the third temperature test direction are relatively accurate.

[0107] When the difference between the test values ​​of the initial temperature test point in the first temperature test direction and the second temperature test direction is greater than the difference threshold, and the difference between the test values ​​of other temperature test points may be greater than the difference threshold, it means that a temperature test point in the first temperature test direction has caused an irreversible impact on the inductive sensor; at this time, the test values ​​obtained at each temperature test point in the third temperature test direction are inaccurate.

[0108] This embodiment determines whether the test values ​​of each temperature test point are accurate through the difference in test values ​​corresponding to each same temperature test point in the first temperature test direction and the second temperature test direction, and generates a test result based on the judgment result; thus making the final test result more accurate, thereby improving the efficiency of the entire inductive sensor test.

[0109] See also Figure 2 On the other hand, the present application provides a multi-channel high and low temperature testing method for an inductive sensor, comprising the following steps:

[0110] Step 1: Obtain characteristic data of the inductive sensor;

[0111] Step 2: generating a number of temperature test points according to the characteristic data;

[0112] Step 3: Generate a temperature test direction according to the temperature test point; the temperature test direction includes a first temperature test direction, a second temperature test direction and a third temperature test direction;

[0113] Step 4: Generate a temperature adjustment signal according to the test data; and perform temperature control on the temperature adjustment module according to the temperature adjustment signal;

[0114] Step 5: Obtain the test values ​​of each test item corresponding to each temperature test point; generate test results according to the test values ​​of each temperature test point.

[0115] Part of the data in the above formula is calculated by removing the dimension and taking its numerical value. The formula is a formula closest to the actual situation obtained by software simulation of a large amount of collected data; the preset parameters and preset thresholds in the formula are set by technical personnel in this field according to actual conditions or obtained through simulation of a large amount of data.

[0116] How this application works:

[0117] The present application generates a number of temperature test points through the characteristic data of an inductive sensor; generates a temperature adjustment direction according to the temperature test points and the sensor characteristic data, the temperature test directions including a first temperature test direction, a second temperature test direction and a third temperature test direction; performs a temperature test on the inductive sensor according to the temperature adjustment direction; during the test, a temperature adjustment signal is generated according to the test data to adjust the test temperature, and a test result is generated according to the test values ​​corresponding to each temperature test point in the first temperature test direction, the second temperature test direction and the third temperature test direction; and generates test schemes for different sensors in a targeted manner according to the characteristic data of the sensor, so that the test scheme is more matched with the corresponding sensor, thereby making the test result of the sensor more accurate.

[0118] The above embodiments are only used to illustrate the technical method of the present application and are not intended to limit it. Although the present application has been described in detail with reference to the preferred embodiments, a person of ordinary skill in the art should understand that the technical method of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present application.

Claims

1. An inductive sensor multi-channel high and low temperature test system, comprising: Data acquisition module, test planning module, test module, temperature adjustment module and interaction module; characterized in that, The data acquisition module: acquires the test data of each inductive sensor in real time through the data acquisition device; The test planning module: obtains characteristic data of the inductive sensor through the interactive module, generates a number of temperature test points according to the characteristic data; generates temperature adjustment directions according to the temperature test points; the generating of temperature adjustment directions according to the temperature test points includes: marking the temperature test point with the highest temperature value as a high temperature test point; marking the temperature test point with the lowest temperature value as a low temperature test point; Obtaining an inductance value 1 of the temperature characteristic curve corresponding to the high temperature test point; and an inductance value 2 of the temperature characteristic curve corresponding to the low temperature test point; Obtain the inductance value three of the temperature curve corresponding to the initial temperature test point; determine whether the difference between the inductance value one and the inductance value three is less than the difference between the inductance value two and the inductance value three; If yes, the first temperature test direction is from the initial temperature test point to the high temperature test point, the second temperature test direction is from the high temperature test point to the initial temperature test point, and the third temperature test direction is from the initial temperature test point to the low temperature test point; If not, the first temperature test direction is from the initial temperature test point to the low temperature test point, the second temperature test direction is from the low temperature test point to the initial temperature test point, and the third temperature test direction is from the initial temperature test point to the high temperature test point; Integrate the first temperature test direction, the second temperature test direction and the third temperature test direction into a temperature adjustment direction in sequence; The test module: generates a temperature adjustment signal according to the test data; performs temperature control on the temperature adjustment module according to the temperature adjustment signal; and obtains the test values ​​of each temperature test point corresponding to each test item, and generates a test result according to the test values ​​of each temperature test point; the test result includes a test data packet and a test signal, and the test signal includes a test completion signal or a third temperature direction retest signal; the generating of the temperature adjustment signal according to the test data includes: Obtain the test data corresponding to the current test cycle at the temperature test point; extract the item time change curve corresponding to each test item in the test data; determine whether all item time change curves are stable; If yes, the detection value corresponding to the stabilized test item is marked as the test value corresponding to each test item at the corresponding temperature test point; a positive temperature adjustment signal is generated; If not, when the accumulated time of the test cycle is greater than the set time threshold, determine whether the temperature adjustment direction is the first temperature adjustment direction; if yes, generate a reverse temperature adjustment signal; if not, generate a stop adjustment signal; otherwise, after the next test cycle is over, obtain and determine whether the time change curves of all items corresponding to the next test cycle are stable; The temperature adjustment signal includes a forward temperature adjustment signal, a reverse temperature adjustment signal and a stop adjustment signal.

2. The multi-channel high and low temperature test system for inductive sensors according to claim 1, characterized in that: The step of generating a plurality of temperature test points according to the characteristic data includes: Obtain the temperature adjustment range of the test equipment and divide the temperature adjustment range into several temperature intervals; Extract the inductor type and inductor material from the characteristic data; search for the corresponding temperature characteristic curve L(T) in the temperature characteristic curve lookup table according to the inductor type and inductor material; By formula Get the distribution coefficient FP of the temperature interval numbered i i ; Among them, T i is the lower limit temperature value of the temperature interval numbered i; BXY is the set slope threshold; By formula Calculate the number of test points corresponding to the temperature interval numbered i, where α is the adjustment coefficient, 0<α<1; BS is the number of standard test points; Set the number of test points evenly within the corresponding temperature range; The temperature characteristic curve lookup table is established by the following steps: Step 1: Obtain several inductors with the same inductor type and inductor material; Step 2: Adjust the test temperature from low to high in sequence to obtain the inductive reactance value of each inductor; Step 3: Take the average value of the inductive reactance values ​​corresponding to each inductor as the inductive reactance value at the corresponding test temperature; Step 4: Use the inductive reactance value at each test temperature as the ordinate and the test temperature as the abscissa to fit the temperature characteristic curve corresponding to the inductor standard and inductor material; Step 5: Obtain temperature characteristic curves corresponding to several inductors of different inductor types and inductor materials; Step 6: Construct a temperature characteristic curve lookup table based on the one-to-one correspondence between the inductor type and the inductor material and the temperature characteristic curve.

3. The multi-channel high and low temperature test system for inductive sensors according to claim 1, characterized in that: The initial temperature test point is a temperature test point in the temperature characteristic curve corresponding to each temperature test point where the inductance value is closest to the inductance calibration value.

4. The multi-channel high and low temperature test system for inductive sensors according to claim 1, characterized in that: The step of judging whether the time variation curves of all items are stable includes: Obtain the time change curve of each project; Divide the project time change curve into several time period curves according to the acceptable stable duration, obtain the variance of the last time period curve, and determine whether the variance is less than the set variance threshold. If yes, mark the project time change curve as a stable state; if no, mark the project time change curve as an unstable state; When all project time variation curves are in a stable state, then all project time variation curves are stable; otherwise, all project time variation curves are unstable.

5. The multi-channel high and low temperature testing system for inductive sensors according to claim 1, characterized in that: The temperature control according to the temperature control signal includes: When the temperature adjustment signal is a stop adjustment signal, the temperature adjustment module of the control test setting stops running; When the temperature adjustment signal is a positive temperature adjustment signal, the current temperature adjustment direction is obtained; and the temperature adjustment module is controlled to enter the next temperature test point according to the direction of the current temperature adjustment direction; When the temperature adjustment signal is a reverse temperature adjustment signal, it jumps to the next temperature adjustment direction; and controls the temperature adjustment module to enter the next temperature test point according to the temperature adjustment direction.

6. The multi-channel high and low temperature test system for inductive sensors according to claim 1, characterized in that: The generating of the test results according to the test values ​​of each temperature test point includes: Obtain the difference between the test values ​​of each same temperature test point in the first temperature test direction and the second temperature test direction of the same test item; Determine whether the difference of each temperature test point is less than the difference threshold; If yes, when the difference between the test values ​​of the initial temperature test points in the first temperature test direction and the second temperature test direction is less than the difference threshold, the test values ​​of each temperature test point in the first temperature test direction are used as the final test values ​​of the corresponding temperature test points; and the test values ​​of each temperature test point in the third temperature direction are also set as the final test values; the final test values ​​of each temperature test point are fitted into a project temperature characteristic curve of the corresponding test item in the order of the temperature test points from low to high; the project temperature characteristic curves of each test item of multiple inductive sensors and the project time change curves of each item corresponding to each temperature test point are packaged to generate a test data packet, and a test completion signal is generated; If not, the test values ​​of each temperature test point in the first temperature test direction are used as the final test values ​​of the corresponding temperature test points, and the final test values ​​of each temperature test point in the first temperature test direction are fitted into partial temperature characteristic curves of the corresponding test items in the order of the temperature test points from low to high; the partial temperature characteristic curves of each test item of multiple inductive sensors and the project time change curves of each item corresponding to each temperature test point are packaged to generate a test data packet, and a re-test signal in the third temperature direction is generated.

7. A method for testing multi-channel high and low temperature of an inductive sensor, based on the operation of a multi-channel high and low temperature testing system for an inductive sensor according to any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Obtain characteristic data of the inductive sensor; Step 2: generating a number of temperature test points according to the characteristic data; Step 3: generating a temperature test direction according to the temperature test point; the temperature test direction includes a first temperature test direction, a second temperature test direction and a third temperature test direction; Step 4: Generate a temperature adjustment signal according to the test data; and perform temperature control on the temperature adjustment module according to the temperature adjustment signal; Step 5: Obtain the test values ​​of each test item corresponding to each temperature test point; generate test results according to the test values ​​of each temperature test point.

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