Analysis of Factor Influence for Longitudinal Impulse of Heavy-haul Train with Electronically Controlled Pneumatic Braking System

Abstract:

The simulation model of electronically controlled pneumatic (ECP) braking system and longitudinal dynamics was built to analyze the influence of initial braking speed, coupler slack and gradient on train longitudinal impulse. The results show that: initial braking speed has no effect on the longitudinal impulse while the gradient affects the longitudinal impulse most, followed by coupler slack; the top 3/8 of train at the rampflat change point is the most dangerous braking position, and this position cannot be changed with the initial braking speed/coupler slack/gradient; when the pressed (tensile) coupler force exceeds 2 000 kN, the maximum value has linear correlation with the minimum (maximum) velocity difference; when the filtered velocity difference is controlled with a range of -0.25~0.25 m?s-1, the possibility that the maximum pressed (tensile) coupler force exceeds 2 000 kN is less than 5%.

Key words:heavy-haul train; electronically controlled pneumatic braking system; longitudinal dynamics; coupler force; gradient