Summary: | 碩士 === 國立臺灣大學 === 化學工程學研究所 === 90 === The ultimate goal of the research is to construct a portable PID auto-tuner. The auto-tuner is developed on the software platform named ScadACS. From the threshold, we hope to develop a methodology suitable for on-line auto-tuning. And we use the relay feedback test, which is sufficient to apply the dynamic information for our auto-tuning procedure.
The auto-tuning procedure is divided into two parts: system identification and controller tuning.
The purpose of model identification is to choose the PID controller tuning rules. Theoretically, the system dynamics can be treated roughly as two classes. One of them includes the FOPDT systems and SOPDT systems with damping factor bigger than 0.7, the other includes the SOPDT systems with damping factor less than 0.7. By a normalized system's relay feedback response curve, we treat the first class as FOPDT dynamics systems and the second class as underdamped SOPDT systems. Each system has its corresponding tuning rules based on parameters obtained from relay feedback test.
Finally, by the method we proposed, we can develop a portable PID auto-tuning module on the software platform ScadACS.
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