Malfunction diagnosis method for the thermal system of a power plant based on thermoeconomic analysis

Abstract

It is difficult to accurately diagnose and locate faults in the thermal system of power plants due to the coupling of multiple components. The goal of the current study is to develop a model that predicts how the thermodynamic parameters–performance curve is changed when one component exhibits anomalies. This model uses the concept of irreversibility in thermoeconomic structure theory as a means of quantitatively measuring changes in the performance of power plant thermal systems. This is achieved by initially filtering out the effect of anomalies on the control regulation system and subsequently comparing the change in performance to reference values, enabling qualitative analysis to decouple component interactions. Following model construction, advanced process simulation is applied to simulate several typical fault conditions in a 330-MW power plant, and the proposed model is used to diagnose the cause of malfunction based on thermoeconomic analysis. The results indicate that the method has satisfactory feasibility for malfunction diagnosis in a complex energy system.