Research On Reliability Test Method Of High-speed Train Drive System

With the sixth increase in speed of China's railways undergone and new train operation diagram implemented,High-speed train has been integrated into people's lives and peoper's daily routine and travel mode have been gradually changed.According to the long-term planning of the China Railway,By the year 2020,China's new high-speed railway will reach 16,000 km.The maximum operating speed of EMU has reached 350km/h at present,and the CRH380D EMU,Produced by Bombardier Sifang(Qingdao)Transportation Ltd.,is soon run on Nanjing-Hangzhou passenger railway line and Hangzhou-Ningbo passenger railway line.Its maximum operating speed is 380 km/h,the maximum test speed is 420 km/h.CRH380AL set up the highest operational test speed record of of 486.1 km/h,and CSR Sifang developed high-speed test train which operational speed is higher than 500 km/h.As the speed increases,drive train not only runs with high-speed and heavy duty,but also endures vibration,shock,and the force from the track surface and the car-body.And the vibration will cause additional dynamic load,deteriorate drive train's operating conditions.The reliability of drive system determines the safe,reliability and economic operation of track vehicles directly,and its fatigue strength check is of great significance to improve the system reliable operation.Due to the actual load is very complex,and the stress generated by the external loads is very sensitive to the structure and some influencing factors of structural life such as thermal deformation cannot be analyzed effectively.So,the present fatigue analysis and reliability forecast model still have some certain limitations.And actual running test for reliability evaluation is costly,long test cycle,and risky.However,now there is no reliability test system which can simulate the high-speed train transmission system's actual dynamic environment.Therefore,in order to quickly expose the inherent flaws of the of high-speed train drive system's various components,optimize product design and manufacturing processes,and improve product reliability,the development of drive system reliability test bench and the study of corresponding test methods are an urgent task.According to the development project of the drive train reliability test bench for high speed train,reliability test method of drive train is studied in this paper.As the preliminary work of the project,the detailed analysis of drive train's load environment is carried out in this paper.A vehicle model that contains the drive system is established and kinetic analysis is carried out,the vibration characteristics and variation laws of the traction motor and gearbox are studied.Based on full investigation of reliability test theory and the technological present status,and according to current standards and the specific requirements of CRC,the reliability test method of drive train for high speed train is studied deeply.A reliability test-bed model for the high-speed train transmission system is built,the compilation method of load spectrum and vibration environmental spectrum is studied,and the kinematics and dynamics analysis of the designed vibration table is conducted.In view of the new drive system's reliability test system,the main work completed as follows.1.Theoretical research and simulation analysis of high-speed train's drive system dynamic behavior were conduced.A comprehensive dynamic analysis for whole vehicle was performed and its simulating model was established based on Adams/rail.Based on the revised German high-speed track spectrum the track irregularities space domain geometry samples were generated as the dynamic model's input excitation signal.The kinematic simulation is carried out,and the vibration response of the motor and gearbox are analyzed,the vibration characteristics and variation laws with the speed and line conditions are studied.2.One new reliability test bench for high-speed train's drive system is developed.Compared with different design schemes,the design proposal of drive system reliability test bench for high speed train is proposed.The reliability test bench model which can realize drive system's load simulation and vibration environment simulation of high-speed trains is set up.The overall structure of the test bench and test program is introduced,the design scheme,structure and function of electrical drive system vibration environment simulation system,test system and test management system were analyzed specifically.3.The measurement of vibratory response and compilation of vibration environmental spectrum.The relative displacement measurement combined with absolute displacement is designed.The compiling method of vibration environmental spectrum based on power spectrum and the time-domain target random signals' generation method of shaking table is proposed.The generated target signal can keep the vibration random component,while still retain the sports-related characteristics.4.Kinematics and dynamics analysis of the shaking table.The forward kinematics and inverse kinematics solution models for the designed vibration table are built.The additional motion,kinematic accuracy of vibration table and the force of actuators and the longitudinal rods were analysised.The calculation of parallel structure's natural frequency is discussed,the results of analyses and calculation provide the references for optimization design of shaking table.5.The study of load spectrum's compilation methods for drive train.Basic structural damage theory,load data statistical methods,torque measurement method and load spectrum's compilation methods were analyzed.This paper concentrates on studying load data statistical methods,torque measurement method and load spectrum's compilation methods.The two torque indirect measuring method is proposed,load data statistical model based on extreme value theory combined with non-parametric density estimation is built,and the program loading spectrum's compilation methods for high-speed train's drive system and the corresponding test procedures were established.