'Advanced Diagnostics – Predictive analysis for Combined Cycle Power Plants through an Integrated Energetic, Exergetic and Thermo-economic method'

摘要

The increasing need of maintenance costs reduction and productivity improvement, called by the strong competition on energy market, led the development of more incisive methods to discover anomalies. Nowadays, advanced diagnostics is crucial for early detection of malfunctions and degradation of the power plant components. Above all, the Thermodynamic analysis, for its intrinsic characteristic of dealing with slow varying phenomena, is one of the most effective tools for predicting anomalies on the whole power system. In the last years a dedicated software, which involves both the Thermodynamic first and second laws, has been developed by Ansaldo Energia, together with University of Genoa. In this paper, the latest release of the tool is presented, along with some examples coming from the daily diagnostics, demonstrating the capabilities of an integrated approach in isolating anomalous system behaviours. As the starting point, the energetic approach was used to implement an online tool for performance calculation of Gas Turbines and the main Combined Cycles components. The second law analysis has been then added in order to obtain both different and redundant information on the condition of the various elements; the exergetic efficiency and, above all, the destroyed exergy have proved to be compelling indicators of the health of Gas Turbines, Steam Turbines, Heat Exchangers and Condensers. Finally, the thermo-economic indicators provide an estimation of the costs of the entropic losses related to the behaviour of the different parts of a power plant: the increase of the exergetic costs, together with the clues stemming from the other performance indicators, allows to point out the origin of malfunction and plan the most worthwhile timing to intervene.