Modeling the Reliability of the Technical State of a Thermal Pump Installation Using a System of Fuzzy Logical Equations of Linguistic Variables

Abstract

Heat pumps are one of the ef fective ways for increasing the energy efficiency of heat supply. Prediction of the technical state of heat pumps is necessary for uninterruptible heat supply of the consumers. In order to create an expert-modelling system for multifactorial analysis of the process of accumulation of influencing factors for the technical state of a heat pump, a mathematical apparatus based on the theory of fuzzy logic and a linguistic variable was used. This method gives an interconnected set of mathematical models, which allows using expert-linguistic information to predict the technical condition of the heat pump, depending on the factors that determine it. The functions of membership of fuzzy estimations of the factors influence on the predicted technical condition of the heat pump are constructed. The tree of the logical conclusion of the hierarchical relations of factors that may influence the state of the heat pump is developed. An assessment was made of the levels of linguistic variables that establish the relationship between factors affecting the technical state of heat pumps using the term-set system. Fuzzy matrices of knowledge were also built on the basis of the introduced qualitative terms, and linguistic statements were made, which correspond to the system of fuzzy logic equations that characterize the surface of the variables belonging to the corresponding terms. The methodology of complex factors for the expert of the project on the assessment of the technical condition of the heat pump is presented, which enables to obtain the appropriate management decisions taking into account quantitative and qualitative excitatory factors that influence the reliability and durability of the operation of the heat pump. In the future, the field tests will be conducted, which allow confirmation of the fuzzy logic model of the heat pump state