Abstract
This paper proposes a new fuzzy auto-tuning algorithm for PID controllers with model classification. In the first stage of the tuning the plant is roughly classified based on a result of a plant identification. Then the PID gains are tuned using a fuzzy rule set prepared for the class. The advantage of the proposed tuning algorithm is summarized as follows : (1) The tuning is robust to disturbance, since the PID gains are modified by investigating the output of a plant which is in operation. (2) The proposed algorithm is effective over a wider range of plants than the conventional fuzzy auto-tuning algorithms. (3) Since identification results are used only for classifying plants, tuning performance is less degraded by identification errors than the identification-design method. Both simulation and experimental results for plants with various dead times and first-order-lags show that the proposed algorithm is effective over a wide range of plants.
