| Recently,with the development of battery technology and the emergence of intelligent track technology,multi-group trolleybus has been paid attention to as a solution to the public transportation problem in densely populated cities.Multi-group trolleybus is a passenger train with multi-axle and multi-cars,and the pneumatic braking system is selected for braking system.The load changes frequently in the running process of multi-group trolleybus,so it is necessary to study the dynamic response characteristics of pneumatic braking system when the load of multi-group trolleybus is transferred.Therefore,the pneumatic braking system of multi-group trolleybus is taken as the research object,and the dynamic response characteristics of the pneumatic braking system during load transfer are studied.Firstly,the composition and working process of the pneumatic braking system of multigroup trolleybus are analyzed,and the structure and working principle of the key components of the pneumatic braking system are studied on the basis of understanding the composition of the pneumatic braking system of multi-group trolleybus.Secondly,the flow capacity of valve components and the pressure and flow change equations of the flow rule in the pipeline are established.Combined with the structure and working principle of key components,the simulation models of proportional relay valve,brake chamber and tandem double-chamber brake valve of multi-group trolleybus are established by using multi-domain simulation software AMESim,and the simulation models are verified.Then,the stress of turning braking of trolleybus is analyzed,and the corresponding equations are established according to the longitudinal motion,transverse motion and yaw motion of trolleybus The force analysis of single wheel braking is carried out,and the mathematical model of single wheel braking is obtained Then,the calculation formulas of longitudinal inter-axle load transfer and transverse coaxial load transfer of multi-group trolleybus are derived.Finally,using the established key components,the simulation model of pneumatic braking system is integrated by using the layout of gas circuit schematic diagram of multi-group trolleybus.On the integrated simulation model,the dynamic response of braking system with longitudinal load transfer and lateral load transfer is simulated and analyzed.The results show that the response time of the brake system meets the requirements of the national standard by simulating the electric control braking response and the pneumatic control dynamic response of the simulation model of the multi-group trolleybus pneumatic braking system;Then,four working conditions are set for longitudinal load transfer and three working conditions are set for transverse load transfer,and the response time of pneumatic braking system under various working conditions is obtained.The research results can be applied to the research on braking strategy of multi-working and multi-group trolleybus. |
PDF Full Text Request