The Calculation and Verification of the High Speed Train Braking Curve

In CTCS-3 train control system,the on-board equipment uses the target distance and continuous speed control mode to control the train.In order to ensure the train safety,the on-board equipment must calculate the braking curve based on the movement authority and adjust the train speed in real time.In this paper,the forces which are applied to the train are analyzed,and the calculation method of deceleration when the train is braking is given.The train braking curves are calculated by using forward and reverse iterative methods.The methods of calculating the train braking curve are proved to be correct.In the process of reversely and iteratively calculating the braking curve,narrowing the distance step can improve the accuracy of the braking curve,selecting the appropriate distance length not only can ensure the accuracy of the braking curve but also can meet the timeliness of calculating the braking curve.and The simulation result proves that the emergency braking distance of CRH2 high-speed trains is 2 780 m,the max normal braking distance is 4 628 m if the initial speed of the train is 300 km/h and the train is running on the flat and straight line.These results comply with the state regulations.The relationship between the deceleration and the speed during the train braking is analyzed in this paper.Moreover,the relationship between the initial braking speed and the braking distance is analyzed in this paper.The result shows that the greater the initial braking speed,the longer the braking distance and the braking distance will increase nonlinearly.