深海微生物培养模拟平台温度控制技术研究

Temperature control system for the simulation platform of culturing deep-sea microbes

针对深海微生物培养系统对温度条件的苛刻要求,在分析系统构成及建模的基础上,介绍了一种对系统的两级滞后环节采用了PI控制和双Smith预估反馈的方法,通过内环和外环Smith预估控制,精确的消除了温度控制系统中滞后延迟环节的影响,提高了PI控制强度,减少了超调,提高了系统动态响应和稳态精度。在系统Matlab仿真和实际实验中得到了良好的效果,满足系统的精度要求。

The temperature control system of the simulation platform for culturing and detecting deep-sea microbes is analysed, and an optimization model of the system is established. Because of the existence of two time-delay components, and the disturbance by ambient temperature and flow rate of the culture fluid in the reactor, general PI control can not cancel the disturbance timely, thus leading to large overshoot, fluctuation of temperature, and bad dynamic performance. But the deep-sea microbes are sensitive to the ambient temperature, so a new approach to control the temperature is needed. The paper introduces a new method, in which PI and dual Smith-predictors are used to eliminate the time-delay in the inner loop and the outer loop. The disturbance of the delay component in the temperature control system is eliminated, thus making PI parameters very easily adjustable, reducing the overshoot, and improving the dynamic response and the accuracy of the steady-state. Good control results are obtained by this approach.