Controller of new automatic pressure regulating valve for electro-pneumatic braking system of commercial vehicles and its experimental study

Automatic pressure regulating valve is the core component of electro-pneumatic braking system of commercial vehicles, whose performance directly affects that of the brake system. In this paper, to realize intelligent braking, the design requirements of automatic pressure regulating valve controller are obtained through a comprehensive analysis of their application conditions and relevant standards. LabVIEW software is used to design a feedforward fuzzy PID (Proportional Integral Derivative) controller for new automatic pressure regulating valve, the test bench based on the response characteristics of which is constructed using a NI data acquisition card, sensors, and automatic pressure regulating valve, etc. The pressure response characteristics of automatic pressure regulating valve under the three control algorithms, namely PID control, feedforward PID control and feedforward fuzzy PID control， are verified by experiments. The experimental results under different algorithms are compared with relevant standards， and the results show that the feedforward fuzzy PID control algorithm provides the best pressure response characteristics of automatic pressure regulating valve with a shorter response time, a smaller overshoot and a better stability. The performance of automatic pressure regulating valve is improved in this paper so that the pressure of brake chamber can be better regulated dynamically, providing technical support for the precise control of commercial vehicle electro-pneumatic braking system.