Proportional Integral Derivative Based Fault Tolerant Control for a Gas Turbine

Abstract

This paper presents a fault tolerant control switching scheme with embedded fault detection and isolation system for the gas turbine of a combined cycle power plant. Mechanical faults of the turbogenerator are considered as case study. Previous to the control design, the detection and isolation capabilities of the gas turbine are studied by applying structural analysis to a first principles based gas turbine model. As a result, a new sensor was suggested to improve the detectability and isolability with respect to mechanical faults and sensors faults. Furthermore, the active fault tolerant control developed is based on stabilizing families of proportional integral derivative (PID) controllers, which are tuned off-line and the plant switching scheme preserves the stability of the whole closed-loop system, thanks to a careful selection of controller according to fault conditions. Simulation results with nonlinear model show the potential of the procedure.