Expert system for operator support

The paper describes the general approach, present state and future prospects of the Expert System for Operator Support (ESOS) developed in the Nuclear Research Institute at Rez near Prague (NRI). This system should be used in the WWER-440 type Nuclear power plant Dukovany. The characteristic features of ESOS are as follows: Main functions of ESOS (process monitoring, diagnostic, advising) are realized by modern ideas of several mutually co-operating expert systems; ESOS is a real-time system connected on-line to the NPP's process; ESOS is pronounced modular system, that enables us to connect additional modules with other functions, or remove of modify some of the original ones; Graphic communication, which simplifies the communication with the user (NPP's operator). The principal features of the all expert systems (RECON, DIAG, ADVISE) and their communication are described in more detail. The experience with creating and testing knowledge bases for diagnostics of steam-generator valves and escapes of cool water (less than 60 t/h) is also described. 3 refs, 4 figs