About Us
Grad Studies
Research Themes
Process Control
Quality process control is essential for the successful operation of any chemical process. At the MACC, we are researching and developing cutting edge control technologies to meet the challenges of today's industry. We are currently looking at process control for continuous, semicontinuous, and batch processes; advanced model predictive control techniques; strategies for detecting and responding to process faults using a safe-parking approach; integrated optimization and control strategies; and strategies for integrated design and control. Advancements in these areas are applied to applications in energy, biofuels, and bulk chemicals.

Industrial process control systems need to be designed to explicitly deal with limitations (constraints) in the capacity of the control actuators and to satisfy bounds on the evolution of the process state variables to prevent severe deterioration in the nominal closed-loop performance and even lead to closed-loop instability. In current industrial practice, the achievement of high performance, under control and state constraints, relies to a large extent on the use of model predictive control (MPC) policies. However, the ability of the available model predictive controllers to guarantee closed-loop stability and enforce constraint satisfaction is dependent on the assumption of feasibility (i.e., existence of a solution) of the constrained optimization problem. This limitation strongly impacts the practical implementation of the model predictive control policies and limits the a priori (i.e., before controller implementation) characterization of the set of initial conditions,... [read more]

Dr. Prashant Mhaskar
Professor and Canada Research Chair in Nonlinear and Fault-Tolerant Control

Traditionally, most of the research in fault-tolerant control has been concerned with preserving nominal process operation in the presence of faults. This has been addressed within the so-called reliable control approaches (which essentially treats the faults as disturbances and designs fault-tolerant controllers) and reconfiguration-based control approaches that assume the existence of a backup control configuration. Yet, there are numerous examples in the chemical process industries where the process economics do not permit deployment of redundant control configurations. In such scenarios, the only recourse is the swift recovery of the failed component. During the fault-recovery period, however, the absence of an established framework to handle such situations, and the use of ad-hoc approaches could lead to the onset of hazardous situations or the inability to resume nominal operation upon fault-recovery. Motivated by these considerations we have developed, utilizing... [read more]

Dr. Prashant Mhaskar
Professor and Canada Research Chair in Nonlinear and Fault-Tolerant Control
Brian MacDonald
MaSC recipient
Maaz Mahmood
Part-time Ph.D. student
Hadi Shahnazari
PhD recipient

Several chemical processes, including specialty chemicals, polymers and pharmaceutical are operated in batch fashion. The control and operation of batch processes, is however intrinsically different from continuous operation, because the control objective is not that of stabilization, but achieving desired values of the process variables at the end of the batch. The desired end-point conditions are not necessarily an equilibrium point of the process, and therefore, the large body of advanced control tools developed for continuous operation are not directly applicable to batch processes. Existing results on batch process operation either rely on open-loop operation policies or set point trajectory tracking for closed--loop operation, or utilize repeated implementation of model predictive control calculations. Existing results, however, do not allow for an explicit computation of the set of initial conditions from where a desired end-point can be reached. The absence of such a... [read more]

Dr. Prashant Mhaskar
Professor and Canada Research Chair in Nonlinear and Fault-Tolerant Control
Masoud Kheradmandi
Ph.D. recipient