The Study On Carbody Hunting's Evaluation Method Of High-speed Train

Whether it is to expand the operating coverage or to enhance the operating speed in the further development of China's high-speed,safety and stability of the train operation are still the focus.Because of the self-oriented performance and the tread which has a certain taper,sinuation motion is the inherent properties of the railway vehicle system.The frequency of a vibration of the carbody is fixed(usually less than 1.6Hz),and the frequency of the sinuation motion of the bogie increases with the speed.Means that two kinds of frequency will close to at a certain speed a,and the the hunting of carbody will occurs and deteriorate the ride quality of vehicle.But because of tread equivalent taper,wheel-to-axis spacing,suspension parameters,running speed,line disturbance,management and other factors,it appears at at a higher speed or even normal operating speed.By comparing the advantages and disadvantages of several hunting evaluation meathods of carbody in the domestic and overseas,the amplitude of displacement as an evaluation index is proposed to estimate the carbody's sinuation.The amplitude algorithm of displacement is realized by Matlab,and its validity and correctness is validated by the vibration acceleration and displacement amplitude of the carbody of one dynamic simulation model.According to the experimental data,the recommended value evaluating the state of hunting of the high-speed train's carbody is presented.Comparing with the stationary index,it is consistent with the stationary index on overall trend and shows more sensitivity.Specific performance as follows:when the car body of the high-speed train isn't hunting,the amplitude index of displacement,by contrast,is much smaller than the upper threshold of the good grade;and when the car body of the high-speed train is hunting,it's higher than the upper threshold of the corresponding unqualified grade.