Modelling of the operation and maintenance tasks of a complex power industry system in the fuzzy technical states space

Technical systems which operate in the power industry are the critical systems of strategic importance. In case of such systems the task consisting in the avoidance of the failure occurrence has an extraordinary significance. The failure occurrence is interpreted as the transition of the system technical state from the area of the ability states to the area of the inability states. Therefore, the identification of the system technical state and determination their ability and inability states areas are the fundamental elements of the rational control of the power industry systems operation and maintenance. The technical state of the system is described by momentary values of its cardinal features. Simultaneously, in case of the complex system where the elements are connected by many multidimensional relationships, it is not obvious to qualify the technical state of a system as the ability state or the inability one. What is more, only the approximated momentary and boundary values of the system features are known. Thus, in the paper, the fuzzy space of the technical states of the system is introduced. In the space the technical state is expressed in a form of the multidimensional fuzzy set and the areas of the ability and inability states are transformed into the fuzzy subspaces. The proposed approach make possible to describe the considered operation and maintenance problem in the analytical manner. Thanks to it, the ability of the system to fulfil its operation tasks can be calculated and analysed. In the end of the paper, the industrial implementation of the proposed method is described. During the carried out research the OP-650k-040 steam boiler was examined. As a results of the studies the adequacy of the method in case of the power industry complex systems was proved.