Model and method of contextual help to develop skills of power unit operator using training simulator

Abstract

Development of operator skills at the facility may lead to significant risks of accidents, and emergency drills in case of accidents “on-site” is impossible. Therefore, the use of computer simulators for operator training is an established international practice. Skill honing means repetition of exercises and is prone to errors. To increase the efficiency of training, computer simulators provide the ability to stop simulation to refer to tutorials. However, tutorials do not provide an immediate solution of the problem, as for what the mistake is and how one should act in a particular situation. The aim of the study is to reduce the time for contextual information search by, first, developing a dynamic model of training scripts, and second, developing a method to interpret the above model and to find error description. Petri net (PN) is an adequate model of action scenarios for a user of a computer application. Petri net links actions and the conditions of their execution. However, in contrast to the actions of the application user, the ability of the operator to perform actions is determined not only by the state of the control interface, but also by the state of the object itself. Thus, it is necessary to improve previously proposed models and methods of their interpretation. A scenario model in the form of an open Petri net (OPN) is proposed. The model novelty is the dynamic marking of positions with the values of the variables of the control object and the presence of transitions that are triggered when discrete signals of the control system are received. The authors propose the method of interpreting OPN queries which returns reference information relevant to the context. A method of integrating contextual help into simulator which projects the state of the object and the operator's actions on the structure of the OPN is proposed. The results of the study have been implemented in 215 MW power unit simulator of Surgut State District Power Station №1, which is being developed by Tekon-Avtomatika LLC. The results can be used during development of computer simulators of similar objects. Linear computation efficiency of the access to context information is provided.