Replacement of process computers and upgrading of the Loviisa nuclear power station's training simulator

The replacement project for the process computer systems at Finland's Imatran Voima Oy (IVO) Loviisa NPP (2x465 MW PWR, in operation since 1977 and 1980) has been started. These systems are of crucial importance to the process monitoring in the control rooms. At the same time the computer systems of the on-site training simulator, operating since 1980, will be upgraded. Both the process computer and the simulator systems were supplied by Nokia Electronics, Finland. Planning of the computer replacement was initiated in 1983 and an agreement with Nokia-Afora was signed in summer 1986 after a hard international competition. The new systems are based on DEC's VAX and Micro VAX computers and a distributed bus (Ethernet) configuration. The high resolution colour display system will be delivered by Ferranti, United Kingdom. The systems will be upgraded so that the simulation computers will be replaced in September 1987, the process computers of Loviisa 1 and the training simulator by the end of 1988 and the Loviisa 2 units by the end of 1989. The paper describes the reasons and justification for replacement, the functional and technical requirements of the new systems, with particular emphasis on the improvements to the present systems, hardware and software solutions and estimated costs of the project. Problems related to the replacement of systems in a running plant are also dealt with. Finally, some ideas concerning further development, such as new functions of the man-machine interface, are presented, as well as plans to minimize the obsolescence problem of the new systems. (author). 2 figs