Based On The Pwm Modulation Gas Valve Pressure Servo Control

With the great development of the railway system, new vehicles, the development of new brake parts, bicycle test process have been carried out several major amendments,and the original length of a bicycle can only detect 14.5m, volume of 15.5L vehicles. With 70-ton vehicles putting into operation in particular, have developed variety of different uses of the vehicles, and the length of vehicles is different, which is from the original 14.5m to the longest 26.5m; so the sealing performance of vehicles tube demands highly, which the tube pressure within the specified time shall not dropped. Therefore, this article according to the train volume of 15.5L pressure time-varying standard curve, Self-tuning aperture, so special designs of the self-regulating instrument of Single Car that makes use of PWM controlling the pulse valve as a compensation. However, for the volume of exhaust pipe is different, the duty cycle that the PWM controls the pulse valve is also different. In this paper, based on the principle of Fuzzy control, through a number of experiments, design the look-up table of Fuzzy controller which can meet variety of models according to the experience control rules, and carried out in the PLC programming.Firstly, this chapter summarize some features and application, including instrument of Single Car, Fuzzy control theory, high-speed solenoid valve, PWM and so on, and in the light of the actual establish a mathematical model; Secondly, designed a conventional Fuzzy controller, Fuzzy control Incremental, self-adjusting factor Fuzzy controller, Fuzzy-PID dual Fuzzy controller, adaptive Fuzzy controller, through the MATLAB simulation results we can see that the adaptive Fuzzy controller can automatically adjust the PID parameters, so that in short time the instrument of Single Car makes the exhaust curve of variety of volume train tracks the ideal exhaust curve to meet the test requirements of variety of models; At the same time, in accordance with the principle of self-regulation instrument of Single Car and performance requirements, proposed upper and lower machine Control Method, and used PLC to control the scene, and design PLC program in detail, which realizes the system initialization, the system state of the collection, and host computer communication etc functions, use of industrial control computer as a PC to monitor on the system, using its powerful computing power to achieve the adaptive Fuzzy control system; Finally, the system completed function test using different cylinders, and a series of test proved that the system run in good condition and achieved the design requirements when the brake volume changed.