Large Scale Control System Theory and Applications

点击翻译按钮获取中文摘要

LARGE SCALE CONTROL SYSTEMS AND APPLICATIONS BACKGROUND: The field of Control Systems and Automation deals with the problem of modifying the behaviour of a system, so that something "desirable" occurs. For example in a chemical factory, which has literally 100's of measurements and 100's of control valves to vary, it is desired that the plant should produce some desired output product , e.g. a polymer. In this case however it is impossible to have a single human or even a group of humans to be able to correctly adjust the valves (inputs) of the plant to achieve the desired product due to the complexity of the plant's behaviour, and due to the fact that disturbances, which are unmeasurable, are always present. To achieve this objective of controlling a plant, a "controller" is used, which typically is a set of instructions on a computer. "Simple plants" generally have a "centralized controller" in which all information of the system is fed into the computer but, for complex systems such as a chemical plant, it is not realistic to have such a centralized controller and a " decentralized controller", which consists of many sub-controllers, each of which are all isolated from each other, is used. The problem however, is that the theory of "decentralized control" is still incomplete, and decentralized control design is still in its infancy. RESEARCH STUDY PROPOSED: The research project proposed is a continuation of previous studies made by the applicant on so called "Large scale control systems theory". In particular the focus is about decentralized control, and in particular the design of decentralized controllers. NEW THEORY PROPOSED: In terms of the new theory being developed, a focus on: (i) Clarifying the properties of decentralized fixed modes (DFM), which are still not well understood, will be made (ii) An attempt on obtaining the fundamental limitations of decentralized control will be made (iii) A new decentralized controller design method for plants will be attempted which has the property that it requires no mathematical model; it is believed that such a design approach is important, because model building is difficult to carry out in industrial systems. (iv) A study of various complex decentralized control design methods will be made. NEW APPLICATION PROBLEMS PROPOSED: In conjunction with new theory, it is of great interest to determine how well the theory actually "works" when applied to real world problems, and so some application problems will also be studied, which are interesting in their own right. (i) A controller for new generation hard disc drive systems will be designed which is believed will be an order of magnitude faster than existing disc drives (Western Digital Corp., Advanced Servo-Mechanical Technologies, San Jose, CA, USA are interested in this new controller design; note:there appears to be no Canadian company to interact with.) (ii) A large generalized electric power management system and decentralized controller for the autonomous mode operation of a microgrid system that includes multiple distributed energy resource (DER) units will be carried out. This type of problem is important in microgrid systems and will be an order of magnitude more demanding than previous studies. (iii) The problem of developing a controller which works "well" for the case of patients with spinal cord injury will be carried out. (iv) A study of the decentralized control of third generation large flexible space structures (LFSS) will be made; in particular necessary and sufficient conditions for a a solution to exist and a controller characterization will be made. The theory will be tested out on applying it to the MSAT II LFSS.