改进的PID算法在输液加温器中的应用

Application of improved PID algorithm in the infusion heater

针对目前市场上的输液加温器在使用过程中常会出现加热温度过高,显示温度与出口温度偏差大的情况。以市售某公司加温器为平台,对加温器的加热过程进行实验研究。在温度控制过程中采用了改进的位置式PID算法,PID参数采用工程整定的方式获得;通过控制可控硅的PWM占空比达到控制加热效果;通过Matlab的曲线拟合功能,获取估测的出口水温与实际出口温度的近似关系。最后经过测试对比,有较好的加热效果和较高的温控精度,符合临床使用的要求。

Aiming at the problem of overtemperature in using infusion heater on present market, and the deflection display temperature and outlet temperature is very large. An experimental research of the heating process of the heater is conducted by taking a heater of a company as the platform. The improved positional PID algorithm is used in the process of temperature control process. The PID parameters are obtained by engineering setting. The heating effect is controlled by adjusting the PWM duty cycle of the thyristor. Through Matlab curve fitting function, the approximate relationship of the estimated and actual outlet temperature is obtained. Finally through contrast test, the heater has good heating effect and higher temperature control precision, can meet the clinic requirement.