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Includes bibliographical references and index. / The design and implementation of a method to software interface high level applications programs used for the control and monitoring of a Particle Accelerator is described. Effective methods of interfacing the instrumentation bus system with a Real time multitasking computer operating system were examined and optimized for efficient utilization of the operating system software and available hardware. Various methods of accessing the instrumentation bus are implemented as well as demand response servicing of the instruments on the bus.

Hybrid systems combine the continuous behavior evolution specified by differential equations with discontinuous changes specified by discrete event logic. Usually these systems in the processing industry can be identified as having to depend on discrete decisions regarding their operation. In process control there therefore is a challenge to automate these decisions. A model predictive control (MPC) strategy was proposed and verified for the control of hybrid systems. More specifically, the dynamic matrix control (DMC) framework commonly used in industry for the control of continuous variables was modified to deal with mixed integer variables, which are necessary for the modelling and control of hybrid systems. The algorithm was designed and commissioned in a closed control loop comprising a SCADA system and an optimiser (GAMS). GAMS (General Algebraic Modelling System) is an optimisation package that is able to solve for integer/continuous variables given a model of the system and an appropriate objective function. Online and offline closed loop tests were undertaken on a benchmark interacting tank system and a heating/cooling circuit. The algorithm was also applied to an industrial problem requiring the optimal sequencing of coal locks in real time. To complete the research concerning controller design for hybrid behavior, an investigation was undertaken regarding systems that have different modes of operation due to physicochemical (inherent) discontinuities e.g. a tank with discontinuous cross sectional area, fitted with an overflow. The findings from the online tests and offline simulations reveal that the proposed algorithm, with some system specific modification, was able to control each of the four hybrid systems under investigation. Based on which hybrid system was being controlled, by modifying the DMC algorithm to include integer variables, the mixed integer predictive controller (MIPC) was employed to initiate selections, switchings and determine sequences. Control of the interacting tank system was focused on an optimum selection in terms of operating positions for process inputs. The algorithm was shown to retain the usual features of DMC (i.e. tuning and dealing with multivariable interaction). For a system with multiple modes of operation i.e. the heating/cooling circuit, the algorithm was able to switch the mode of operation in order to meet operating objectives. The MPC strategy was used to good effect when getting the algorithm to sequence the operation of several coal locks. In this instance, the controller maintained system variables within certain operating constraints. Furthermore, soft constraints were proposed and used to promote operation close to operating constraints without the danger of computational failure due to constraint violations. For systems with inherent discontinuities, a MPC strategy was proposed that predicted trajectories which crossed discontinuities. Convolution models were found to be inappropriate in this instance and state space equations describing the dynamics of the system were used instead. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2002.

The control of electrical drives, or motion control, is important in modern industry. In order to satisfy the requirements of industry, it is important for tertiary institutions to produce graduates skilled in this field. The theoretical content of a typical electrical engineering course will prepare students to tackle design and offline simulation of a digital motion controller. However, to gain an in-depth understanding of the field, students need to be able to implement and test their designs in practice. The complete design process of a digital motion controller is an inherently lengthy process requiring a number of diverse skills, for example microprocessor based hardware and software design. While hardware design issues can be minimised by a choice of a commercially available controller board, the coding of real-time software for a complex controller can pose a steep learning curve. At the undergraduate level, students seldom will possess sufficient practical expertise to fully implement a challenging motion control design in the limited time frames allocated for such projects. This thesis presents a complete rapid prototyping environment for the design of motion control, the Control System Development Environment (CSDE). The CSDE allows a seamless progression of a motion control project through all stages, from initial design and simulation, through real-time implementation to final online tuning and validation. Users are freed from all low-level software and hardware design issues. In the context of undergraduate design projects, the CSDE allows students to design, simulate and prototype challenging solutions in the limited time available. Thus, students can gain in-depth, system level expertise in the design of motion control without being hampered by low-level design issues. The CSDE has been successfully tested by a number of undergraduate students at the Department of Electrical Engineering at the University of Natal. In particular, the CSDE's effectiveness has been demonstrated by its application during two prize winning final year design projects.