Design Solution And Simulation Research Of Ecp Brake System For Heavy Haul Train

For railway freight, the heavy haul transportation is efficiency measure that can expand and increase railway transportation, but also an important way that alleviate the economic development to the railway transportation pressure. Along with increasing load in railway wagon, grouping more and more, also growing more of axle load, the problem on the manipulation about vehicle brake or ease become more prominent, therefore, improve the braking performance of the freight trains,especially the heavy haul train’s braking performance is particularly critical. Conventional pneumatic brake system due to its inherent limitations, improving braking performance is limited, need to seek a brake syatem can breakthrough the limitations of conventional pneumatic brake system. In this background, the electronically controlled pneumatic brake system came into being.This paper chose the Electronically Controlled Pneumatic (ECP) brake system on heavy haul train’s for study. By reference to foreign ECP brake system’s structural characteristics, then design a wired overlap ECP braking system for China railway freight train. And then use AMESim software to modeling and simulation analysis of ECP brake system.The core of the brake system is the control of the braking force, so when study on heavy haul train ECP brake System, mainly focuse on the vehicle control unit and stand-by pneumatic brake system. The vehicle control unit includes:brake force distribution, brake directive definition, brake cylinder pressure control. Stand-by pneumatic brake system is making use of traditional120-type brake valve to control.Modeling the ECP brake system in AMESim software,the ECP brake system includes:brake cylinder pressure control model,the isolation module model,implementation of the electro-pneumatic module model, stand-by pneumatic brake model as well as motorcycles and block trains brake system model,then motorcycles and block trains brake system model are simulated. In the brake cylinder pressure control model, though vehicle braking rate, vehicle load and the parameters of the foundation brake device to define brake cylinder target pressure and broke through the conventional pneumatic brake system’s brake force distribution. The simulation results of motorcycles brake system show that:in the ECP mode wired overlap ECP braking system simplifies train’s control, the driver can adjust the braking force according to requirements of any train operation, when train in accident case (brake pipe leakage), the brake pipe pressure is less than 300kPa, the low pressure cut valve in isolation module take an action, then apply emergency braking. The simulation results of block trains brake system show that: in ECP mode, the vehicle can be synchronized braking. The results of the150block trains equipped with the braking system for emergency braking distance show that: compared with the stand-by (traditional pneumatic) brake mode, the braking distance of the ECP mode is reduced by24.5%. Therefore, the ECP brake system has the performance that can not be achieved by conventional pneumatic brake system, is a better way to improve the heavy haul train’s braking performance.