Research On Parameter Detection And Contact Degradation Mechanism Of The Railway Relay

With the development of economy and technology,the railway industry has been developing rapidly.With demand for equipment control in railway system growth,the reliability of its performance also have higher requirements.As an important electrical equipment in railway system automatic control and remote communication,relay is of great significance for the safe operation of the railway system.Contacts are the important part of the relay system;related research has aroused wide concern.Around the core of the contact performance,this paper has carried out research on the two aspects of the parameter acquisition,calculation and the microscopic appearance of the degradation of the relay.First of all,relay electric life testing were performed,the relevant electrical parameters were collected,the relay time parameter that can reflect the performance of relay was studied and calculated,and the calculation results were compared with the measured data to verify the accuracy of the algorithm.Secondly,in the study of the degradation of the contact surface topography,considering the great effect caused by the change of morphology of the contacts,the 3D shape acquisition,scanning electron microscope image(SEM)and energy spectrum analysis results(EDS)of wear contacts were obtained,surface fractal dimension was calculated.A qualitative analysis was made of the relationship between the shape characteristic parameters,contact resistance and contact pressure.To find out the morphology parameters which are more influence of the contact performance,the method of grey correlation analysis and entropy weight was used.Taking the parameters as input,the BP neural network was optimized by genetic algorithm,and the correlation model between shape parameters and contact performance is established.After verification,the model meets the accuracy requirements.It provides a new way to study the contact performance of the relay.