Concepts of integrated information and control systems for future nuclear power plants

New control rooms which fully utilize CRT displays to improve information presentation to operators are in commercial operation in Japan. On the basis of lessons learned from the Three Mile Island accident, development of the computerized operator support systems (COSSs) within the Ministry of International Trade and Industry's project was undertaken to aid operators in diagnosis and decision making under abnormal plant conditions. The key functions developed in COSSs, for example, guidance for control rod operation and for post-trip operation as well as advanced information presentation techniques with CRT displays, have been incorporated into the design of the advanced new control rooms (ACRs) for ABWRs and APWRs. Almost all normal plant operations, including control rod operations, will be automated and fundamental operations required in a post-trip situation will also be automated in ACRs. Consequently, the operator's role will be shifted to the supervisory control of the plant, including maintenance management and planning of operation. In the light of recent developments in artificial intelligence, a national project 'Advanced Man-Machine System for Nuclear Power Plants' (MMS) has been carried out since 1984. MMS has been developing plant functional models based on the operators' cognitive processes and strategies for diagnosis and procedure synthesis as its knowledge bases. Using these, MMS develops supports for operators' behaviour based on knowledge levels and intelligent man-machine interfaces with interactive capability corresponding to the operators' cognitive processes. Integrating MMS functions into ACRs, intelligent information and control systems with user-friendly man-machine interfaces will support operators' decision making in highly automated future nuclear power plants. 8 refs, 2 figs, 1 tab