The Research On Fuzzy Control Of Ventilator With Flow-By Funtion

Ventilator is a very common and important medical device in hospital. It can control the flow to the patient for replace or help the respiration of patient. The control quality of ventilator can have important impact on the treatment effect. So this study tries to find out the new control method to improve the treatment effect and comfort level of patients.The main research includes:Firstly, the model of ventilation system/respiration system dynamics model is built according to analysis of real human respiration system and hydromechanics. Then according to dynamics of respiration system, the nonlinearity time-varying dynamics model of respiratory system is established. The correctness of the model is validated by clinic data, and ventilator dynamic model is set up according to ventilator dynamic characteristic. Secondly, the different control methods are compared in the model set before, and find out the PI model’s dynamic property and normal fuzzy control’s steady-state performance are not good, that may cause the patient’s uncomfortable. Finally, the fuzzy control is used with flow-by function to improve the performance of the whole system. The result is ideal. The dynamic property and the steady-state performance are better than the PI control or the normal Fuzzy control. And it improves the therapeutic effect and the comfort level of patients.