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Controls and Control Theory Commons

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Articles 1 - 4 of 4

Full-Text Articles in Controls and Control Theory

Performance And Robustness Issues In The Compensation Of Folpd Processes With Pi And Pid Controllers, Aidan O'Dwyer Jan 1998

Performance And Robustness Issues In The Compensation Of Folpd Processes With Pi And Pid Controllers, Aidan O'Dwyer

Conference papers

This paper will discuss the compensation of first order lag plus time delay (FOLPD) processes using PI and PID controllers whose parameters are specified using appropriate tuning rules. The gain margin, phase margin and maximum sensitivity of the compensated system as the ratio of time delay to time constant of the process varies, are used as ways of judging the performance and robustness of the system.


The Gain Scheduled Piece-Wise Adaptive Digital Control Of A Ph Process, Eugene O'Shaughnessy, Aidan O'Dwyer Jan 1998

The Gain Scheduled Piece-Wise Adaptive Digital Control Of A Ph Process, Eugene O'Shaughnessy, Aidan O'Dwyer

Conference papers

The compensation of a pH process is complicated by the non-linear nature of the process titration curve and the significant time delays that typically exist in such processes. This paper will propose the use of a gain scheduled piecewise adaptive PI controller to compensate the process. A pilot plant is controlled, with the control algorithm implemented on a programmable controller. SCADA software displays and trends the plant and controller signals.


Compensation Of Processes With Time Delays, Thomas Heeg, Aidan O'Dwyer Jan 1998

Compensation Of Processes With Time Delays, Thomas Heeg, Aidan O'Dwyer

Conference papers

Methods which allow comparisons in the use of PI and PID controller strategies for the control of first order lag plus time delay processes (FOLPD) are worthy of investigation because of the relative lack of work done in this area. In this paper, strategies for comparing performance and robustness for a PI or PID controlled FOLPD process are analysed and designed. The use of different PID controller structures for processes with time delay is also worth considering in detail. Various PID controller structures are compared by means of servo and regulator time responses, Bode plots and Nyquist plots.


The Identification And Control Of Processes With Time Delay, Susan Carr, Aidan O'Dwyer Jan 1998

The Identification And Control Of Processes With Time Delay, Susan Carr, Aidan O'Dwyer

Conference papers

The identification of the frequency response and process model parameters of systems with time delay using frequency domain techniques is evaluated in this paper. The performance of both Fourier Transform and Power Spectral Density techniques is considered. The benefits of employing modern model based design and delay compensation techniques, based on the identified process data, are assessed.