Vector-based deterioration index for gas turbine gas-path prognostics modeling framework

Abstract

This study presents a conceptual modeling framework for gas path prognostics of the gas turbine, to improve condition monitoring knowledge. The structure contains main concepts related to power plant performance degradation, reliability degradation, and the relationships between these concepts. Potential fault modes, physical age, deviation factors of performance parameters, and new vector-based deterioration index are some components of the framework. The deterioration index vector has been defined as resultant of deviation factors of performance parameters in an orthogonal system. This vector value is function of physical age. The framework has been obtained from the survey of experimental and semi-empirical data for various types of gas turbines. Some limited parts of the structure have been implemented for a 100 kW micro gas turbine. The prognostic has been simulated in two parts. The first simulation was performance analysis for different fault modes of the compressor with fixed electrical power. The turbine inlet temperature was increased for all compressor fault modes. The second simulation was the analysis of fixed compressor fault mode for one-year with variable power. The annual fuel consumption was increased by 3.29%, and the mean remaining useful life of the turbine was reduced 88% in one-year operation.