Control and Alarm Systems Interplay and Co-design

  • Author / Creator
    Mohammad Hossein Roohi
  • Monitoring systems are indispensable parts of industries that are responsible to guarantee the safe and proficient operation of plants.
    As a part of monitoring systems, alarm management systems are deployed to prevent damage to components, and improve safety and quality of products.
    The main concern in alarm system design is to provide a mechanism for the accurate announcement of abnormal behavior of plants.
    However, in reality, numerous false and missed alarms could compromise the overall proficiency.
    In this thesis the effect of control systems, as a missing (but significant) actor, on the performance of alarm systems is studied.
    The interplay of control and alarm performance is justified and it is shown that a controller that is designed to achieve a good quality-of-control (in terms of minimum output variance) has either desirable or undesirable consequences on the performance of alarm systems.
    To pave the path for finding a robust controller design, a new alarm index is introduced and an analytical expression is derived to evaluate the performance of signals, known systems and systems with parameter uncertainties.
    A set of linear matrix inequalities (LMIs) is proposed for the controller design to satisfy the required control and alarm performance.
    Then, we propose a new method to obtain optimal alarm filters by incorporating the knowledge of plant and control systems.
    In the last part of the thesis, we propose an analytical framework to design and evaluate the performance of two types of non-linear alarm filters.
    Moreover, in industrial environments, many process variables are acquired.
    So one challenge is to identify the process variable that provides the best alarm performance after filtering.
    We derive an analytical solution to this problem considering specific types of non-linear filters.

  • Subjects / Keywords
  • Graduation date
    Spring 2021
  • Type of Item
  • Degree
    Doctor of Philosophy
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.