Modeling And Simulation Research Of 100% Low Floor Light Rail Vehicle Braking System

With the development of urbanization in our country, urban light rail vehicles have been developing rapidly. Especially the 100% low floor light rail vehicle becomes common for its energy-saving, high-comfort and low cost. Over the years, braking system technology of low floor light rail vehicles has been in foreign monopoly, and the domestic braking system technology is not mature enough, yet the performance of the braking system directly affects the safety operation. Therefore, it has a vital significance to research 100% low floor light rail vehicle braking system.In this paper,100% low floor light rail vehicle braking system in 2M1T three marshalling module was taken as the investigated subject. According to the requirements of the function and braking performance in "General technical specification for low floor tramcar" and "Railway applications-Braking-Mass transit brake systems-Part 1: Performance requirements", plus on the basis of reference to the low floor light rail vehicle braking system at home and abroad, the design of the project was completed.100% low floor light rail vehicle braking system is composed of electro dynamic braking system, hydraulic braking system and magnetic track braking system, these three components are independent but coordinated. A brake unit and a brake control unit are included in the hydraulic braking system.The brake unit, which is the core of the braking system, is divided into a foundation brake unit and a hydraulic brake unit. On the basis of analyzing the working principle and structure of its main components, simulation models of these components were established by AMESim, and then their working performances were analyzed.For the brake control unit, according to the 100% low floor light rail vehicle braking control strategy, vehicle control unit, electro dynamic brake unit, magnetic track brake unit and brake control unit were modeled by using signal components library in AMESim.Furthermore, a complete 100% low floor light rail vehicle braking system was modeled. Performance curves of braking distance, braking deceleration, braking force distribution and brake cylinder pressure were obtained by the simulation research on service brake, emergency brake, security brake and anti-slip protection under different load conditions. According to performance curves, the performance of these braking modes was analyzed in aspects of braking time, braking distance and braking deceleration.In the end, a low floor light rail vehicle brake calculation software, which can realize calculation function of service brake, emergency brake, security brake and parking brake, was designed according to "Railway applications-Methods for calculation of stopping and slowing distances and immobilization braking-Part 6:Step by step calculations for train sets or single vehicles". It is an effective and efficient computing tool for the research and development of the low floor light rail vehicle braking system. By comparing calculation results of this software with simulation results, the correctness of the simulation results was verified.