模糊鲁棒控制器在结晶过程中的应用

Application of fuzzy robust controller in crystallization

结晶是提纯物质的重要方法,广泛应用在制药和化工工业中,但结晶是一个具有多变量、时变性、不确定性的复杂过程,不同阶段有不同的控制要求,结晶罐温度和液位控制间又存在一定的耦合,传统PID控制难以达到较好地控制效果,因此针对这一复杂过程提出了模糊鲁棒控制的方法,首先通过串联解耦消除青霉素结晶过程中存在的耦合,然后建立系统的T-S模糊模型,在T-S模糊模型基础上采用H∞鲁棒控制算法进行仿真研究。仿真结果表明所设计的状态反馈H∞控制器可以较好地对系统实现控制,整个系统具有较好的鲁棒性,并对实际青霉素结晶过程的优化控制提供一定的理论指导意义。

Crystallization is an important method to purify substances and is widely applied in pharmacy and chemical indus tries. Penicillin crystallization is a complicated process with variable time, uncertainy and multi-variables. The requirement of control in different stages is variable and there is some coupling between temperature and liquid level control in the tank. Traditional PID control is difficult in attaining better control effect. In response to this complex project, this paper proposed fuzzy robust control methods. First the coupling in penicillin crystallization process is eliminated by series deeoupling compensator. Then T-S fuzzy model of the system is constructed. H∞ robust control method is used in T-S fuzzy model. Simulation results show that state feedback H∞ controller can control the system effectively, showing that the whole system has better robustness. It offers reference for practical penicillin crystallization.