Linguistic If-Then Rules in Large Scale Application of Fuzzy Control

In this Chapter, we will describe a large scale application of fuzzy control, which has been realized in the Czech Republic. It concerns the enterprise, which is a part of the Metallurgic Plant Břidlicna, a.s., an important producer of the high quality aluminium in the Czech Republic. The applications of fuzzy control started in 1995. After good experiences with the first furnace fuzzy control, it was decided to apply it on the other four furnaces one by one, too. At present, the system works in the whole enterprise on all five furnaces. We have used the linguistically oriented fuzzy logic controller, for which it is specific to interpret the IF-THEN rules as linguistically characterized logical implications and the inference is logical deduction based on the formal fuzzy logic in broader sense.