Research On Loading Method Of Multi-channel Fatigue Test Bench Of Bogies

With the rapid development of China’s high-speed rail, the demand of high-speed bogie’s performance is becoming much stricter. Fatigue test bench of multi-channel hydraulic servo system can be used to test fatigue strength of bogie frame and to evaluate life and reliability of the frame with the help of line measured data.However, there is a problem of mutual interference between galleries during multi-channel load fatigue test, and the interference of more galleries, heavier load is more distinct especially for those big ones. For example, during fatigue test of bullet train’s frame, there are seventeen galleries, and its accuracy of test will be reduced irrespective of their mutual interference.The paper is mainly aimed at checking and calculating servo hydraulic system, eliminating mutual interference between galleries’load according to the make-up of hydraulic pressure signal. First of all, the theory, method and steps of fatigue are introduced, additionally, the whole process of bogie’s fatigue test is explained by the example of CRH380B. Secondly, electro-hydraulic position servo system offered by MTS Company is checked and calculated, the transfer function block diagram is modeled for this test bench’s symmetric hydraulic servo system with the use of hydraulic transmission knowledge, and stability of fatigue test electro-hydraulic position servo system is analyzed. Finally, stiffness matrix of system is built with the remote parameter control theory, and interference is eliminated by the signal make-up of hydraulic.According to the study, function of electro-hydraulic position servo system offered by MTS Company is totally fitted with demand of fatigue test bench load, accuracy of testing load is improved by hydraulic signal make-up. Fatigue test bench will be used to test fatigue of kinds of high-speed steering frame, laying the foundation of China’s high-speed rail steering frame’s fatigue and reliability evaluation.