Research Initiation Award: Synthesis of Pseudo-Fuzzy Logic Controls for Chemical Processes

化学处理系统通常是非线性和复杂的。工业中的控制操作员往往依靠自己的经验和启发式（或简单的常识）来控制一个复杂的过程。模糊逻辑控制是一种有效的方法，可以很容易地结合启发式方法。模糊逻辑控制是基于模糊集理论，其目的是允许定量测量定性描述，如高，大，小等在人类推理中经常使用。模糊集是隶属度值在0到1之间的数的集合，其中0表示最弱隶属度，1表示强隶属度。本研究计划将研究伪模糊控制器（PFLC）在复杂非线性化学过程控制中的应用。PFLC基于传统的模糊逻辑控制器，但它将启发式转换为具有可调参数的代数方程（模糊逻辑集使用决策表）。该方法包括伪模糊逻辑模型的推导，其中融合了获取模型结构的合流方法和系统辨识的调制函数方法。然后将启发式转换为PFLCs。系统性能可以分析使用现代控制方法，如频率响应，李雅普诺夫或H∞方法。通过显式求解伪模糊逻辑模型中的控制变量，可以得到新的规则。为了研究PFLC的实际应用，还将进行聚合反应器温度控制的实验研究。该体系将聚合聚二甲基硅氧烷。

Chemical processing systems are typically nonlinear and complex. Control operators in industry tend to rely on their own experience and heuristics (or simple common sense) to control a complicated process. Fuzzy logic control is an efficient method which can easily incorporate heuristics. Fuzzy logic controls are based on fuzzy set theory which is designed to allow quantitative measurements of qualitative descriptions such as tall, large, small, etc. used frequently in human reasoning. A fuzzy set is a set of numbers having membership values between 0 and 1, where 0 signifies weakest membership and 1 signifies strong membership. This research project will investigate pseudo-fuzzy logic controllers (PFLC) for the control of complex nonlinear chemical processes. PFLC is based on conventional fuzzy logic controllers but it translates heuristics into algebraic equations (fuzzy logic sets use decision tables) with tunable parameters. The methodology includes the derivation of pseudo-fuzzy logic models which incorporate confluence methods for obtaining model structure and modulating function methods for system identification. Heuristics are then translated to PFLCs. System performance can be analyzed using modern control methods such as frequency response, Lyapunov or H infinity methods. New rules can be obtained by explicitly solving for the control variables from pseudo-fuzzy logic models. To investigate the practical applications of PFLC, an experimental study of temperature control of a polymerization reactor will also be performed. The system will be the polymerization of polydimethylsiloxanes.