A STUDY ON WATER-LEVEL CONTROL OF PWR STEAM-GENERATOR AT LOW-POWER AND THE SELF-TUNING OF ITS FUZZY CONTROLLER

The water level control system of the steam generator in a pressurized water reactor and its control problems are analysed. In this work, a stable control strategy during low power operation and transient state s is studied. The control strategy employs substitutional information using the bypass valve opening instead of incorrectly measured signal at the low flow rate as the fuzzy variable of the flow rate during low power operation, and includes the flexible scale adjusting method for fast response at a large transient. A practical self-tuning algorithm based on the control performance and the descent method is also sugge sted and applied to tuning the membership function scale of the flow e rror.