Precise Control Research On Brake System Equalizing Reservoir Pressure Based On Ep Valve

For heavier and faster, in addition to have a higher traction power, the train needs more powerful, efficient and reliable braking devices. Now mainly adopt braking devices are on the basis of the air brake, or electro-pneumatic brake, both at home and abroad. With the improvement of train traction weight and speed, considering the safety and ride comfort (mainly refers to passenger cars), the precise control of the train braking system air pressure has put forward to higher quality, therefore, a good performance of air pressure control system is essential in the braking system.In this paper, the braking system equalizing reservoir pressure to be as research object. Based on understanding of domestic and international pressure control strategy of the braking system, it established a set of pneumatic system by using of on/off EP valve, and designed the control strategy so as to realize the precise control of the equalizing reservoir pressure.Because of the compressed air as the medium of the brake system, the paper studied the theoretical characteristics of the compressed air, firstly. Then, analyzed the structure of the on/off valve and simplified dynamic characteristics research content. Applied principle of module partition, the on-off valve system is divided into four subsystems, electrical, magnetic, mechanical, and pneumatic. Modeled and analyzed each of the subsystem respectively in AMEsim software platform for dynamic simulation and analyzed the simulation result, those works provided a theoretical basis for determining the on/off valve response performance and the structure parameter setting and improvement. Using two on/off valves and a sensor composed of a on/off EP valve, then, designed control strategy of the on/off EP valve. At the beginning, used the traditional PID algorithm for EP valve control, established the equalizing reservoir pressure and simulated in the AMEsim platform. The result showed that this system using traditional PID algorithm quickness and accuracy satisfied the requirement of system design, but stability was a little poor, so introduced the fuzzy control that adopted two-dimensional fuzzy controller, defined the subordinate function, the domain and the fuzzy subset of each variable. According to the role of three PID parameters, the relationship between each other and different deviation and the deviation change rate, the paper designed three parameters of fuzzy PID control rule table and co-simulated the fuzzy PID control system in Simulink and AMEsim platform. Compared with traditional PID control, the result showed that the system accuracy and stability were better and satisfied the requirement of the system.