Abstract
The basic control system involves the determination of the control signal over the prescribed time interval such that closed-loop design objectives are satisfied. Many of the conventional design methods for control systems rely on the fixed design configurations. The designer decides the basic configuration of the overall system and the place where the controller is to be positioned. Thereafter, the parameters of the controller are designed based on the process dynamics. The commonly used system configurations with controller compensation are the series compensation and the feedback compensation. These compensation schemes have one degree of freedom in that there is only one controller in each system, even though the controller may have more than one parameter that can be varied. The disadvantage of the one-degree-of-freedom controller is that the performance criteria that can be realized are limited. These drawbacks can be overcome by some compensation schemes, such as the series-feedback compensation and the series compensation with the setpoint filter, that have two degrees of freedom. This chapter presents systematically several dead-time compensation structures for tackling the problems associated with controlling stable, integrating and unstable processes with time delay. Disturbance rejection in process industries is commonly much more important than setpoint tracking for many process control applications. Cascade control structures for improving the load disturbance rejection performances are also presented. Several simulation studies are provided to demonstrate the efficacy of the novel control structures.
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Majhi, S. (2012). Control Structures for Time Delay Systems. In: Vilanova, R., Visioli, A. (eds) PID Control in the Third Millennium. Advances in Industrial Control. Springer, London. https://doi.org/10.1007/978-1-4471-2425-2_8
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DOI: https://doi.org/10.1007/978-1-4471-2425-2_8
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