Nonlinear control of gas turbine system under disturbances: An integral backstepping, terminal synergetic and fuzzy logic approach

The deep penetration and inherently uncertain nature of renewable power generation systems make it a challenging task to design reliable control systems for any device interfacing with the power grid. Gas turbines are considered the elective transitional power generation technology. In this article, we propose an advanced robust control system not covered in literature for a power generating Gas Turbine (GT) system utilizing non-linear control theoretical principles. The focused GT system is expressed by a state variables representation of the non-linear mathematical model. GT speed is controlled by determining the fuel demand response of GT under variable load conditions. The novel Integral Backstepping Controller (IBC), Backstepping Controller (BSC), Terminal Synergetic Controller (TSC) and Fuzzy Logic Controller (FLC) are here considered and compared to get the desired GT speed. Overall global asymptotic stability of the GT system has been proved with the help of the Lyapunov theory. Furthermore, stability analysis is formulated to validate the proposed control methods by observing the system's performance subject to noise disturbances. MATLAB/Simulink environment has been used for the implementation of simulations to observe the settling time and state errors. Performance curves for each proposed controller are compared with the classical PID controller. Results obtained from the simulation work are utilized in a comparison analysis based on the graphical and statistical data. Conclusions drawn from the study show that the non-linear controllers have significant improvements as compared to PID controller's performance, with limited increased complexity, while among non-linear controllers, IBC shows the best performance. • Proposed an advanced robust control system not covered in literature for a power generating Gas Turbine (GT) system. • Upgraded the classical Backstepping algorithm with the integral action for all system error equations. • Advancement in the Synergetic control with terminal property to get system's convergence in finite time. • Proved superiority of non-linear controllers over the linear control. • Efficiency in fuel consumption and robust speed control of system under uncertainty.