Robust Controller Design for Systems with Constraints

本研究项目旨在开发过程控制 处理约束和不确定性的算法。 约束会影响控制器的设计，因为当动态 许多进程的行为可以用一个 线性模型，系统运行始终受到 约束是非线性的元素。 该控制器具有 来处理这些非线性。 等 约束可由致动器饱和或处理引起 限制（某些温度和压力可能不适用） 例如，超过）。 不确定性是一个因素，因为 控件设计器从来没有完美的动态描述 任何真实的工业过程的（模型）。 该系统 近似和模型阶次和参数始终包含 有些误差，甚至可能随操作条件而变化。 PI计划实施两种技术来处理此类问题。 问题，模型预测控制（MPC）和抗饱和 无颠簸传输（AWBT）。 MPC要求控制 目标用一个二次方程表示， 目标函数和约束被转化为 线性不等式约束 AWBT控制器设计 分两步进行，首先， 设计了一种忽略所有非线性回路元件的控制器 和目标。 然后增加补偿方案， 处理约束等非线性问题。 这 研究将分三个步骤进行： (1)将设计一种新的鲁棒线性MPC控制器。 它 将通过优化器以非线性方式实现 其目的是满足所有过程约束， 最小化与线性行为的偏差。 (2)开发一种AWBT合成程序， 的 平滑切换性能、测量 噪声 灵敏度和鲁棒性。 (3)建立机制， 目标和约束转化为MPC或AWBT形式主义， 有效的方式。

This research project is aimed at developing process control algorithms to handle both constraints and uncertainty. Constraints affect controller design because while the dynamic behavior of many processes can be accurately described by a linear model, system operation is always subject to constraints which are nonlinear elements. The controller has to be designed to handle these nonlinearities. Such constraints may arise from actuator saturation or processing limitations (certain temperatures and pressures may not be exceeded, for example). Uncertainty is a factor because the control designer never has a perfect dynamic description (model) of any real industrial process. The system is approximated and model order and parameters always contain some error, and may even change with operating conditions. The PI plans to implement two techniques for dealing with such problems, Model Predictive Control (MPC) and Anti-Windup Bumpless-Transfer (AWBT). MPC requires that the control objective is expressed in terms of a single quadratic objective function and the constraints are translated into linear inequality constraints. AWBT controller design proceeds in two steps where first an acceptable linear robust controller is designed neglecting all nonlinear loop elements and objectives. Then a compensation scheme is added which deals with the nonlinear issues such as constraints. This research will proceed in three steps: (1) A new robust linear MPC controller will be designed. It will be implemented in a nonlinear manner through an optimizer which aims at satisfying all process constraints while minimizing the deviation from linear behavior. (2) Development of an AWBT synthesis procedure that balances the trade-offs between smooth switching performance, measurement noise sensitivity and robustness. (3) Development of mechanisms to translate practical objectives and constraints into an MPC or AWBT formalism in an effective manner.