Based On Fuzzy Pid Control Of The Ventilator Pressure Control

Pressure control is the basic of medical ventilator control, and guarantee for medical ventilator work safety and effective. In this experiment, research of pressure control on experiment platform using fuzzy control, evaluate results for fuzzy control.According to common ventilator pneumatic pressure control structure and principles,build experimental platform to investigate the control performance . Firstly, design experimental platform gas path, and set up the pneumatic structures. According to system requirements, design hardware circuit for experiment platform to detect pressure and flow rate and solenoid valve control. Write the under part software for signal detection, transmission and output control signal. Write the PC software for display, set, storage, and control functions.Analysis of fuzzy control and PID control principle, design a fuzzy PID control scheme for the breathing machine system characteristics. According to the dynamic response features of PID and features of ventilator system, design the fuzzy controller, simulate and output the control algorithm using MATLAB's fuzzy control toolbox. Using the fuzzy controller, according to E(error) and EC(error change) ,change values of PID parameters, to achieve the set pressure.Select the three different pressures, using the traditional PID control and fuzzy PID control on experiment platform, analysis two methods overshoot, control error, control time and control stability. The results show that, fuzzy PID control is more effective in suppression of the overshoot, and reducing the control error, and there is also a certain advantage in controlling time. Fuzzy PID control is superior to conventional PID control. Fuzzy PID control section controls the pressure in the different effects are relatively stable, while the traditional PID control section control the effect of different pressure difference between the large, robust fuzzy PID control is better than traditional PID.