Safety Protection Method Of Shunting Operation In Station Based On GNSS

Shunting operation in railway station plays an important role in railway transportation system.Many factors have high requirements for drivers’ driving skills,such as complex station environment,dense lines,busy operations,frequent changes in the marshalling state of shunting trains,most locomotives are electric transmission diesel locomotives,the braking mode is mainly air braking,and the braking process is hysteretic.This leads to frequent accidents such as signal jumping,turnout splitting and derailment,which seriously affects the operation safety and efficiency.Therefore,it is of great significance to study the safety protection methods of shunting operation in the station.The key to the safety protection of shunting in the station is to realize the safe and precise positioning of the shunting train,to realize the accurate calculation of the movement state of the train,and to establish the speed monitoring and protection curve.Based on this,combined with the special line environment in the station and the characteristics of the locomotive,this thesis studies the safety protection method of shunting in the station based on global navigation satellite system(GNSS).The main work of this thesis is as follows:(1)A method of locomotive location in station based on GNSS is proposed.Aiming at the difficulties in positioning such as many parallel tracks with small spacing,complex and dense turnouts in the station,a Bayesian estimation algorithm considering the occupation state transition is proposed.The tracks that may be occupied by the locomotive are put into the alternative set,and the set is constantly updated,evaluated and selected;In the process of initial positioning and tracking positioning,maximum likelihood estimation algorithm and Kalman filter algorithm are used to realize accurate positioning respectively;The calculation method of train set position is given.Through experiments,the accuracy and accuracy of the proposed positioning method are analyzed,and the effectiveness and superiority of the positioning method are verified.(2)The dynamic model of shunting train set is established.The force and calculation method during the operation of train set in the station are analyzed;The principle of air braking is analyzed,the air braking delay model is established,and the curve is fitted and solved by the least square method based on the experimental data;The operation equation of shunting train set under discrete time step is given;Finally,the availability and accuracy of the air braking delay model are verified by experiments.(3)The safety protection method of shunting train is put forward.The safe position envelope of train set based on GNSS is established;In view of the particularity of shunting train braking,the calculation methods and results of air braking emergency braking curve,emergency braking trigger curve and alarm curve suitable for shunting train are put forward,which solves the problem of safe braking calculation of shunting train;According to different operation scenarios,corresponding safety protection schemes are established.(4)An example of shunting safety protection in station based on the method in this thesis is given.The shunting operation plan of the actual station is selected,and the results and errors based on GNSS positioning are analyzed.During the operation of shunting train,the speed monitoring protection curve and the actual running curve of train are given,which verifies the safety of the protection method in this thesis.Through the experimental analysis and safety protection examples of each chapter,the safety protection method of shunting in the station based on GNSS proposed in this thesis can effectively ensure the safety of shunting operation,which is of great significance.This thesis includes 63 figures,9 tables,59 references.