The visual illustration of complex process information during abnormal incidents

One of the proposed solutions to the man-process interface problem in nuclear power plants is the integration of a system in the control room that can provide the operator with a display of a minimum set of critical plant parameters defining the safety status of the plant. Such a system has been experimentally validated using the Loviisa training simulator during the fall of 1982. The project was a joint effort between Combustion Engineering Inc., the Halden Reactor Project, Imatran Voima Oy and VTT. Alarm systems are used in nuclear power plants to tell the control room operators that an unexpected change in the plant operation state has occurred. One difficulty in using the alarms for checking the actions of the operator is that the conventional way of realizing the alarm systems implies that several alarms are active also during normal operation. The coding and representation of alarm information will be discussed in the paper. An important trend in control room design is the move away from direct, concrete indication of process parameters towards use of more abstract/logical representation of information as a basis for plant supervision. Recent advances in computer graphics provide the possibility that, in the future, visual information will be utilized to make the essential dynamics of the process more intelligible. A set of criteria for use of visual information will be necessary. The paper discusses practical aspects for the realisation of such criteria in the context of nuclear power plant. The criteria of the decomposition of the process information concerning the sub-goals safety and availability and also the tentative results of the conceptualization of a PWR-process are discussed in the paper