Reliability Of Pantograph In High Speed Train

With the development of electrified railway,people rely much heavily on high speed train.Pantograph and catenary compose the main part of the electric system which serves as the power source for the electric locomotive.The reliability of the pantograph makes a great significance on the safe running of the high-speed train.Given that the common failure and abnormal situation appeared to pantographs,this paper makes analysis on the strength reliability,size error motion precision reliability and wear error motion precision reliability,respectively,based on related theory.Firstly,in order to reduce or avoid the pantograph structural problem resulting from strength failure,strength reliability of a pantograph is analyzed.Based on the finite element method,ISIGHT experiment design method,and neural network technique,the limit state function of strength reliability is received.Combined with random perturbation technique,first order second moment method and matrix differential method,the reliability and reliability sensitivity are computed.The proposed approach to reliability is validated by Monte Carlo simulation method,the sensitivity analysis shows that the influence of load on the pantograph reliability is much greater than that of material property,and the effect of Poisson's ratio is greater than those of elastic modulus and density of the material,that the load and material parameters should be strictly controlled in the process of design and manufacturing.Secondly,to ensure the precession of output motion and avoid the pantograph appear arc discharge which can burn the sliding strip,this paper make analysis on the output motion precision reliability.Based on the the theory of error and the motion of the stress-strength interference model,the limit state function of the pantograph movement precision reliability is obtained.Considering the size error of bars,utilize fourth order moment and Edgeworth series method to research on the output performance reliability of pantograph mechanism.The method of reliability proposed in this section is proved by Monte Carlo method that it has a high precision and can be used in the design process of pantograph.Finally,considering the bad effects exerted on the output performance of pantograph head by the kinematic pair wear of mechanism,the output motion precision reliability is further analyzed.Kinematic pair wear extent is obtained using Archard wear model and is fitted a curve with Gamma degradation model;Based on the theory of effective length and the motion error theory,the limit state function of the pantograph movement precision reliability is obtained.Similarly,combined with fourth order moment,Edgeworth series method and Monte Carlo method,the output performance reliability is calculated and validated.Compared with the results in Chapter 3,the reliability shows a reduction,which indicates the importance to take into account the wear during the design of pantograph.