CN111596205A - Relay service life prediction test system based on degradation sensitive parameter change trend analysis - Google Patents
Relay service life prediction test system based on degradation sensitive parameter change trend analysis Download PDFInfo
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- CN111596205A CN111596205A CN202010505450.1A CN202010505450A CN111596205A CN 111596205 A CN111596205 A CN 111596205A CN 202010505450 A CN202010505450 A CN 202010505450A CN 111596205 A CN111596205 A CN 111596205A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
- G01R31/3278—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches of relays, solenoids or reed switches
Abstract
The invention relates to a relay service life prediction test system based on degradation sensitive parameter change trend analysis, which is characterized in that: including relay action control unit, environmental stress control unit, relay load electrical stress unit, measuring element and main control unit relay action control unit's input is connected environmental stress control unit's output, relay load electrical stress unit's output, measuring element's output and main control unit's output respectively, relay load electrical stress unit's output still is connected with main control unit's input, main control unit respectively with environmental stress control unit and measuring element both way junction. The invention realizes the functions of automatic control, real-time acquisition of test data and intelligent analysis of the relay key characteristic parameter testing process, thereby being capable of carrying out the analysis of the relay degradation trend and the prediction of the service life, and the testing platform has stronger application value.
Description
Technical Field
The invention belongs to the technical field of relays and relates to a relay service life prediction testing system based on degradation sensitive parameter change trend analysis.
Background
An electromagnetic relay is a commonly used electromechanical element and is widely applied to control, isolation and protection circuits of electronic products. For applications requiring high reliability and long life, the service life of the relay is a factor that must be considered in the product design process, and the common method is to evaluate it by reliability life test.
However, in the current relay related test standards in China, most of the related test standards only specify the process and conditions of the service life test, and the unqualified parameters such as contact resistance, action voltage, release voltage and the like are used as the failure criterion of the relay in the test process, so that the time parameter reflecting the wear degree of the product and the service life characteristic changing along with the time are ignored, and the reliable service life of the product cannot be accurately evaluated.
Therefore, how to obtain the characteristic parameters related to the service life of the relay and predict the service life by using the characteristic parameters is a blank in the field and is also an urgent problem to be solved in the field.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides a relay life prediction test system based on the analysis of the variation trend of degradation sensitive parameters.
The technical problem to be solved by the invention is realized by the following technical scheme:
a relay life prediction test system based on degradation sensitive parameter variation trend analysis is characterized in that: the relay action control unit is connected with the output end of the environmental stress control unit, the output end of the relay load electrical stress unit, the output end of the measuring unit and the output end of the main control unit at the input end thereof, the output end of the relay load electrical stress unit is also connected with the input end of the main control unit, and the main control unit is respectively connected with the environmental stress control unit and the measuring unit in a bidirectional way;
the relay action control unit is used for driving the electromagnetic relay to execute actions and switching the development board of the measurement and control circuit;
the environment stress control unit is mainly used for setting the operation parameters of the environment test box and feeding back the actual operation state to the main control unit;
the relay load electric stress unit is used for providing corresponding load for the relay;
the measuring unit is used for measuring the contact resistance and the contact breakover voltage drop of the relay in real time;
the main control unit is mainly used for providing a human-computer interaction interface; controlling parameter setting and running state monitoring of a relay action control unit, an environmental stress control unit and a measuring unit; the system is communicated with an environmental stress control unit, a measuring unit and a relay action control unit through a USB (universal serial bus) card and a GPIB (general purpose interface bus) card; and test data storage and data real-time analysis functions are provided.
The relay load electric stress unit is mainly composed of a programmable alternating current power supply or a programmable direct current power supply and an electronic load.
Furthermore, the relay load electric stress unit is used for providing corresponding load for the relay, and the load comprises contact point voltage and current.
Moreover, the measuring unit is realized by a multifunctional data acquisition instrument.
The main control unit is completed by an industrial control computer and mainly comprises an instrument parameter setting module, a test parameter setting module, a data acquisition real-time display module, a failure criterion setting module and a service life prediction algorithm setting and analyzing module;
the instrument parameter setting module is used for setting communication addresses, transmission rates and response time of a relay action control unit, an environmental stress control unit and a measuring unit in the system;
the test parameter setting module is used for setting the project, the test condition and the test sequence of the service life test of the relay, the driving current, the test switching frequency, the load current type size and the action frequency of the relay to be tested and the test precision of the measuring unit;
the data acquisition real-time display module is used for dynamically displaying various parameters in the relay test process in real time;
the failure criterion setting module is used for setting conditions for judging the failure of the relay and processing measures for the failure;
the service life prediction algorithm setting and analyzing module is used for predicting the service life of the collected relay test data.
And the service life prediction algorithm setting and analyzing module is used for predicting the service life of the collected relay test data, the service life prediction method adopts a thermal fatigue-based relay contact resistance degradation model, the model is embedded into a test system in a dynamic connection library manner for a tester to select and call, and the relay degradation trend rule is obtained by analyzing the time sequence of the test result.
The invention has the advantages and beneficial effects that:
1. the relay service life prediction test system based on the degradation sensitive parameter variation trend analysis is used for analyzing characteristic parameters related to service life aiming at a failure mechanism related to degradation (aging) from common failure modes and mechanisms of relays; a set of test system for key characteristic parameters of the relay under different environmental stress conditions is designed by utilizing a main control unit, a relay action control unit, an environmental stress control unit, a relay load electrical stress unit and a measurement unit, and the functions of automatic control, real-time test data acquisition and intelligent analysis of the test process of the key characteristic parameters of the relay are realized by optimizing software and hardware design, so that the degradation trend analysis and the service life prediction of the relay can be carried out, and the test platform has high application value.
2. The relay service life prediction test system based on the degradation sensitive parameter variation trend analysis can reflect the real degradation characteristic of the relay and predict the service life level of the relay by monitoring the characteristic parameters in real time.
3. According to the relay service life prediction test system based on the degradation sensitive parameter variation trend analysis, the relay degradation time relation distribution characteristics can be obtained through the relay contact resistance degradation model, and the direction can be directly guided for failure analysis work.
4. According to the relay service life prediction test system based on the degradation sensitive parameter variation trend analysis, a relay user can obtain the relay degradation data expressions of different suppliers in the system application, and the relay degradation data expressions can be used as the assessment indexes of the supplier supply quality.
5. According to the relay life prediction test system based on the degradation sensitive parameter change trend analysis, the life prediction based on a test and a relay contact resistance degradation model can more clearly show the degradation time change distribution characteristic of the relay, help judge the inflection point from the random failure period to the aging period, and can be used as the judgment whether the relays in use enter the aging period or not, so that a whole batch replacement decision can be made or more spare parts can be provided.
6. According to the relay service life prediction test system based on the degradation sensitive parameter change trend analysis, the obtained fault time characteristic and degradation time characteristic provide data support for development enterprises to develop tests such as a fault excitation test, a reliability development test, an acceleration model and the like in the research and development stage of the relay.
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FIG. 1 is a schematic block diagram of the system of the present invention;
FIG. 2 is a flow chart of the operation of the present invention.
Detailed Description
The present invention is further illustrated by the following specific examples, which are intended to be illustrative, not limiting and are not intended to limit the scope of the invention.
Characteristic quantities that may be used to reflect changes in relay failure rate over time are identified from the relay failure modes and mechanisms. On the one hand, according to analysis, the contact resistance, the pull-in current, the pull-in time, the release current and the pull-in time of the relay are all possibly used as characteristic quantities for predicting the service life of the relay. On the other hand, the service life characteristics of the relay cannot be influenced by parameters such as environmental stress and load current. Therefore, the test system must also acquire environmental stress parameters in real time and establish a corresponding life evaluation or life verification method according to the degradation model of the contact resistance of the relay.
A relay life prediction test system based on degradation sensitive parameter variation trend analysis is innovative in that: the relay action control unit is connected with the output end of the environmental stress control unit, the output end of the relay load electrical stress unit, the output end of the measuring unit and the output end of the main control unit at the input end thereof, the output end of the relay load electrical stress unit is also connected with the input end of the main control unit, and the main control unit is respectively connected with the environmental stress control unit and the measuring unit in a bidirectional way;
the relay action control unit is used for driving the electromagnetic relay to execute actions and switching the development board of the measurement and control circuit; the main functions that it accomplishes include: (1) the relay driving circuit to be tested can drive 32 relays in total; (2) responding to the relay action command, and measuring parameters of action time and release time; (3) and measuring and controlling circuit switching functions required by real-time measurement.
The environment stress control unit is mainly connected with a programmable environment test box, consists of a test box internal controller or a special control card, and is mainly used for setting the operation parameters of the environment test box and feeding back the actual operation state to the main control unit;
the relay load electric stress unit is used for providing corresponding load for the relay;
the measuring unit is used for measuring the contact resistance and the contact breakover voltage drop of the relay in real time;
the main control unit is mainly used for providing a human-computer interaction interface; controlling parameter setting and running state monitoring of a relay action control unit, an environmental stress control unit and a measuring unit; the system is communicated with an environmental stress control unit, a measuring unit and a relay action control unit through a USB (universal serial bus) card and a GPIB (general purpose interface bus) card; and test data storage and data real-time analysis functions are provided.
The relay load electric stress unit mainly comprises a programmable alternating current power supply or a programmable direct current power supply and an electronic load, and the unit requires that the voltage and the current can be adjusted in real time.
The relay load electric stress unit is used for providing corresponding load for the relay, and the load comprises contact point voltage and current.
The measuring unit is realized by a multifunctional data acquisition instrument.
The main control unit is completed by an industrial control computer and mainly comprises an instrument parameter setting module, a test parameter setting module, a data acquisition real-time display module, a failure criterion setting module and a service life prediction algorithm setting and analyzing module;
the instrument parameter setting module is used for setting communication addresses, transmission rates and response time of a relay action control unit, an environmental stress control unit and a measuring unit in the system;
the test parameter setting module is used for setting the project, the test condition and the test sequence of the service life test of the relay, the driving current, the test switching frequency, the load current type size and the action frequency of the relay to be tested and the test precision of the measuring unit;
the data acquisition real-time display module is used for dynamically displaying various parameters in the relay test process in real time;
the failure criterion setting module is used for setting conditions for judging the failure of the relay and processing measures for the failure;
the service life prediction algorithm setting and analyzing module is used for predicting the service life of the collected relay test data.
The service life prediction methods of the relay are various, and different algorithms have certain differences on the service life prediction results of the relay. From the perspective of practical application, the system selects a thermal fatigue-based relay contact resistance degradation model according to a main failure mechanism and induced stress of a relay, realizes a corresponding prediction model and algorithm, and is embedded into a test system in a dynamic connection library manner for a tester to select and call. And obtaining a relay degradation trend rule by analyzing the time sequence of the test result.
In order to further verify the effectiveness of the test system, 30 certain types of 5A (rated current) electromagnetic relays are randomly selected to carry out a +85 ℃ high-temperature aging test. In the test process, each relay is closed for 1 s-test-disconnection every 60s, and the contact resistance test result of each sample contact is recorded in sequence. The results show that each test result is basically consistent with the test result of the single pair of samples, and the test results can be automatically recorded. The system is designed to meet the expected requirements.
The testing steps of the relay sample on the testing system are as follows:
initializing a relay life prediction test system, and setting a communication address, a speed and response time;
step two, setting specific life test conditions, such as environment test types, test stress conditions and test step sequences, according to specific test requirements;
setting parameter test requirements of the tested relay, such as driving current, frequency, load current and test action times;
step four, setting the precision of parameter testing;
step five, executing a condition test and a relay parameter test;
step six, reaching the condition of stopping the test, such as the parameter degradation reaches the specified threshold value, or the number of the test failure samples reaches the specified number;
step seven, selecting a relay contact resistance degradation model and a corresponding service life prediction algorithm, and substituting the data into the selected model and algorithm for processing, wherein the data mainly relate to: failure time (or action times), failure number in unit time, parent number, recorded data of characteristic parameter degradation, relative time and the like;
and step eight, finally outputting a service life prediction result through the inspection of the relay contact resistance degradation model and the estimation of the model parameters.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.
Claims (6)
1. A relay life prediction test system based on degradation sensitive parameter variation trend analysis is characterized in that: the relay action control unit is connected with the output end of the environmental stress control unit, the output end of the relay load electrical stress unit, the output end of the measuring unit and the output end of the main control unit at the input end thereof, the output end of the relay load electrical stress unit is also connected with the input end of the main control unit, and the main control unit is respectively connected with the environmental stress control unit and the measuring unit in a bidirectional way;
the relay action control unit is used for driving the electromagnetic relay to execute actions and switching the development board of the measurement and control circuit;
the environment stress control unit is mainly used for setting the operation parameters of the environment test box and feeding back the actual operation state to the main control unit;
the relay load electric stress unit is used for providing corresponding load for the relay;
the measuring unit is used for measuring the contact resistance and the contact breakover voltage drop of the relay in real time;
the main control unit is mainly used for providing a human-computer interaction interface; controlling parameter setting and running state monitoring of a relay action control unit, an environmental stress control unit and a measuring unit; the system is communicated with an environmental stress control unit, a measuring unit and a relay action control unit through a USB (universal serial bus) card and a GPIB (general purpose interface bus) card; and test data storage and data real-time analysis functions are provided.
2. The system for testing the life prediction of the relay based on the analysis of the variation trend of the degradation sensitive parameters as claimed in claim 1, wherein: the relay load electric stress unit is mainly composed of a programmable alternating current power supply or a programmable direct current power supply and an electronic load.
3. The system for testing the life prediction of the relay based on the analysis of the variation trend of the degradation sensitive parameters as claimed in claim 1, wherein: the relay load electric stress unit is used for providing corresponding load for the relay, and the load comprises contact point voltage and current.
4. The system for testing the life prediction of the relay based on the analysis of the variation trend of the degradation sensitive parameters as claimed in claim 1, wherein: the measuring unit is realized by a multifunctional data acquisition instrument.
5. The system for testing the life prediction of the relay based on the analysis of the variation trend of the degradation sensitive parameters as claimed in claim 1, wherein: the main control unit is completed by an industrial control computer and mainly comprises an instrument parameter setting module, a test parameter setting module, a data acquisition real-time display module, a failure criterion setting module and a service life prediction algorithm setting and analyzing module;
the instrument parameter setting module is used for setting communication addresses, transmission rates and response time of a relay action control unit, an environmental stress control unit and a measuring unit in the system;
the test parameter setting module is used for setting the project, the test condition and the test sequence of the service life test of the relay, the driving current, the test switching frequency, the load current type size and the action frequency of the relay to be tested and the test precision of the measuring unit;
the data acquisition real-time display module is used for dynamically displaying various parameters in the relay test process in real time;
the failure criterion setting module is used for setting conditions for judging the failure of the relay and processing measures for the failure;
the service life prediction algorithm setting and analyzing module is used for predicting the service life of the collected relay test data.
6. The system for testing the life prediction of the relay based on the analysis of the variation trend of the degradation sensitive parameters as claimed in claim 5, wherein: the service life prediction algorithm setting and analyzing module is used for predicting the service life of the collected relay test data, and a thermal fatigue-based relay contact resistance degradation model is adopted in the service life prediction method.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113504469A (en) * | 2021-09-13 | 2021-10-15 | 广东电网有限责任公司东莞供电局 | Relay state comprehensive online monitoring and fault diagnosis device |
| CN113933698A (en) * | 2021-10-15 | 2022-01-14 | 中车大同电力机车有限公司 | Relay life prediction method and device |
| CN114252731A (en) * | 2021-12-13 | 2022-03-29 | 广西电网有限责任公司桂林供电局 | Relay action characteristic evaluation method and device based on multiple parameters |
| CN114355177A (en) * | 2021-11-10 | 2022-04-15 | 广州辰创科技发展有限公司 | Relay mechanical life testing method and system |
| CN114740303A (en) * | 2022-06-13 | 2022-07-12 | 山东中安电力科技有限公司 | Fault monitoring system of wireless passive high-voltage switch cabinet |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102393501A (en) * | 2011-10-14 | 2012-03-28 | 哈尔滨工业大学 | MOSFET reliability test analysis system and method thereof |
| CN102621488A (en) * | 2012-04-17 | 2012-08-01 | 哈尔滨工业大学 | System and method for testing storage performance of aerospace electromagnetic relay |
| CN103592615A (en) * | 2013-01-10 | 2014-02-19 | 国家电网公司 | Intelligent testing device of built-in load switch of electric energy meter |
-
2020
- 2020-06-05 CN CN202010505450.1A patent/CN111596205A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102393501A (en) * | 2011-10-14 | 2012-03-28 | 哈尔滨工业大学 | MOSFET reliability test analysis system and method thereof |
| CN102621488A (en) * | 2012-04-17 | 2012-08-01 | 哈尔滨工业大学 | System and method for testing storage performance of aerospace electromagnetic relay |
| CN103592615A (en) * | 2013-01-10 | 2014-02-19 | 国家电网公司 | Intelligent testing device of built-in load switch of electric energy meter |
Non-Patent Citations (1)
| Title |
|---|
| 王军;姚力;章江铭;胡瑛俊;沈建良;: "基于GPIB和单片机的继电器测试系统设计与实现", 科技通报, no. 11, pages 183 - 187 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113504469A (en) * | 2021-09-13 | 2021-10-15 | 广东电网有限责任公司东莞供电局 | Relay state comprehensive online monitoring and fault diagnosis device |
| CN113504469B (en) * | 2021-09-13 | 2022-01-21 | 广东电网有限责任公司东莞供电局 | Relay state comprehensive online monitoring and fault diagnosis device |
| CN113933698A (en) * | 2021-10-15 | 2022-01-14 | 中车大同电力机车有限公司 | Relay life prediction method and device |
| CN114355177A (en) * | 2021-11-10 | 2022-04-15 | 广州辰创科技发展有限公司 | Relay mechanical life testing method and system |
| CN114355177B (en) * | 2021-11-10 | 2023-09-19 | 广州辰创科技发展有限公司 | Relay mechanical life test method and system |
| CN114252731A (en) * | 2021-12-13 | 2022-03-29 | 广西电网有限责任公司桂林供电局 | Relay action characteristic evaluation method and device based on multiple parameters |
| CN114252731B (en) * | 2021-12-13 | 2024-04-05 | 广西电网有限责任公司桂林供电局 | Relay action characteristic evaluation method and device based on multiple parameters |
| CN114740303A (en) * | 2022-06-13 | 2022-07-12 | 山东中安电力科技有限公司 | Fault monitoring system of wireless passive high-voltage switch cabinet |
| CN114740303B (en) * | 2022-06-13 | 2022-08-26 | 山东中安电力科技有限公司 | Fault monitoring system of wireless passive high-voltage switch cabinet |
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