A FUZZY CONTROLLER BASED ON SELF-TUNING RULES FOR THE NUCLEAR STEAM-GENERATOR WATER-LEVEL

It was demonstrated that the fuzzy control method could be applied suc cessfully to control and regulate the nuclear steam generator water le vel through previous works. However, this method has some limitations from the fact that its performance largely depends on the tuning metho d and how to settle the rule base. In this work, a fuzzy control algor ithm based on self-tuning rules is investigated to find the optimal tu ning point and to generate the control rule automatically. It adopts a n on-line iterative method and the objective error function which cont ains the variation errors of all time-steps. The triangular membership functions based on the mass flow rate and water level errors are appl ied. And also, a forgetting factor is used to account for an exponenti al decay of the past data in tracking the slow drift in system paramet ers. Thus it controls the steam generator water level from low power t o full power with a little transients. This control algorithm is valid ated by computer simulations.