An operator support system for a Swedish Nuclear Power Plant control room

This paper describes a computerized operator support system called SAS-II. It has been developed under a joint research and development programme between Unit 2 at the Swedish nuclear plant Forsmark, the Swedish Nuclear Inspectorate (SKI), the Swedish State Power Board and the OECD Halden Reactor Project in Norway. The purpose is to develop a function oriented advisory system to assist the shift supervisor in his observation and evaluation task after plant disturbances leading to emergency shut-down. To monitor this shut- down process the supervisor today applies a set of function oriented emergency procedures. When SAS-II is installed the idea is that the system continuously gives information to support the work with the emergency procedure as well as alarms if, and explains why, critical safety functions are challenged. The SAS-II system consists of two parts. One part is developed and executed under control of the real-time expert system shell G2. A knowledge-base has been constructed that represents non-successful behavior of the plant automatics and control systems in terms of the defined plant critical safety functions. The other part of SAS-II consists of a man-machine interface for the shift leader developed and executed under control of the PICASSO graphic display system. The paper first gives an overview of various activities which have been undertaken at Forsmark to improve reactor safety. The major part of the paper describes how SA-II was built and integrating at the training simulator at Forsmark. 9 refs., 4 figs., 2 tabs