Contact Motion Analysis And Performance Degradation Study Of Railway Relay

With the rapid economic development in recent years,railways,as one of the main modes of transportation in China,play an increasingly important role,which also puts forward higher requirements for the safety of the railway system.As a commonly used switching device in railway control systems,relays directly affect the stability of railway transportation for their long-term safety and reliability.The failure of railway relays under actual operating conditions will experience a long-term performance degradation process.If certain parameters of the railway relay in the performance degradation test can be used to detect the current performance degradation degree of the relay and evaluate its operating status,the failure of the railway control equipment can be largely avoided,and the safe operation of the entire railway system can be guaranteed.As the main execution part of the railway relay contact system,the contact is of great significance to the research on the performance degradation of the relay.First of all based on the basic structure of railway relays,this article refers to relevant standards and the purpose of this article to conduct performance degradation tests,design and build railway relay life test equipment and control systems,Using this equipment,real-time detection of the time and electrical parameters of the relay during the test,periodic measurement of other types of parameters,and completion of the overall design of the railway relay performance degradation test program.Secondly,in order to study the movement process of the relay contact,according to the characteristics of the contact movement and the actual test environment,select the appropriate hardware and build a high-speed camera measurement system,design a scale suitable for the contact tracking test,track the captured moving images,and obtain the basic movement curve of its dynamic and static contacts,combined with the dynamic performance characteristics of the relay,the actual movement process of the contact is analyzed,the research results can accurately obtain the motion parameters such as the contact over travel,the maximum speed and acceleration of the contact in the dynamic process,the amplitude and the number of bounces of the dynamic and static contacts.Using oscilloscope and high-speed camera to simultaneously collect electrical parameters and moving images of the relay,analyze the secondary release process of the relay from two aspects,Studies have shown that the secondary release process will prolong the release time of the relay and reduce the contact breaking speed,resulting in an increase in the arcing time and increased corrosion between the contacts,thereby reducing the contact performance of the relay.Then by analyzing the movement process of the contact and combining the relevant knowledge of material mechanics,a non-contact mechanical parameter measurement method based on contact movement analysis is proposed,It replaces the original manual test method of contact gap and contact pressure.The results prove that this method reduces the measurement error and does not cause contact pollution.Finally,taking the contact performance of the relay as the ultimate goal,six characteristic performance parameters including motion parameters are selected,and the gray correlation analysis with the contact resistance is performed to verify the correlation between them.The partial least square method was used to perform regression analysis on the single group contacts and the whole relay.The research method in this paper also has a certain reference significance for the research of contact movement and performance degradation of other switch-controlled electrical appliances.