Researche On The Relationship Between The Longitudinal Impulse And The Operation Of Passenger Trains

The vibration produced in the running of the train passenger train ride is an important source of discomfort.It includes: the vibration acceleration(longitudinal acceleration,vertical acceleration,lateral acceleration),the body in circular curve is not balanced acceleration,change not balanced centrifugal acceleration rate,roll speed,etc.Among them,the longitudinal acceleration is related to the driver's control.Driver's loading,unloading,braking,relieving,and dynamic braking may all cause longitudinal acceleration changes,resulting in a longitudinal impulse.From the point of view of driver manipulation,this paper studies the relationship between driver manipulation and train longitudinal impulse,and puts forward some countermeasures to optimize the operation and enhance the train stability.Based on the principle of train longitudinal dynamics,this paper analyzes the running resistance(basic resistance,ramp resistance,curve resistance),braking force and traction force of the train.Using UM dynamic simulation software to simulate the actual situation of the operation,It is concluded that the train longitudinal impulse law can be implemented under the condition of straight line,long ramp and undulating ramp,such as l adding / reducing load,braking / relieving,dynamic braking and so on.By using the digital stationary instrument,taking the current mainstream speed-raising train as the research object,the data collection of the same train and the same section train is carried out twice,and the actual situation of the driver's longitudinal impulse under the normal operation condition is analyzed.A comparative analysis of typical impulses is made.Simulation analysis shows: The operation of adding / reducing load,braking / relieving will cause longitudinal impulse of train,which is related to train running speed and longitudinal section of line.When adding / reducing load,the greater the tractive force at one time,the greater the longitudinal impulse;When braking/relieving,the greater the amount of brake pressure,the greater the longitudinal impulse;The higher the speed of operation,the lower the longitudinal impulse,whether it is adding / reducing load,braking / relieving;In dynamic braking,the longitudinal impulse is small when the train is running at high speed,and the line disturbance will produce obvious longitudinal impulse when passing through the undulating ramp.The measured results shows: The operation of loading / reducing,braking / relieving and so on all caused different degrees of longitudinal impulse of train,and the law is the same as that of simulation analysis.The longitudinal impulse produced by loading,relieving and high speed dynamic braking is less than 0.08 g,which is not the main factor to produce longitudinal impulse in actual operation.The longitudinal impulse of trains caused by large traction unloading,air braking,and low speed power braking is prominent,The longitudinal impulses of trains caused by large traction unloading,air braking,and low speed power braking are prominent.When the loading / reducing,braking / relieving operations are closely connected,the loading and relieving operations will also cause obvious longitudinal impulses,it is the main cause of train longitudinal impulse in actual train operation.By synthesizing the results of simulation and practical analysis,the method of train stationary operation is put forward,which can be used as a reference for driver's working practice.