Event-Triggered Adaptive Integral Higher-Order Sliding Mode Control for Load Frequency Problems in Multi-area Power Systems

The study proposes a method to design continuous-time event-triggered adaptive integral higher-order sliding mode control for load frequency problems in multi-area power system under load disturbances and parameter uncertainties. Event-triggered strategy reduces the communication burden and lowers the control updating frequency while ensuring high-performance system stability. Event-triggered integral higher-order sliding mode control is used to attain need-based chattering-free control signal compared to event-triggered integral sliding mode control which assures its easy practical implementation. Adaptive estimation of switching gain is used with higher-order integral sliding mode control that eliminates the need of prior knowledge about the system uncertainties. Nonlinear uncertainties in power system like generation rate constraints (GRC) and governor deadband lead to load disturbance that results in deviation of frequency from its nominal value. Robustness of the controller is tested for plant considered with such nonlinearities. System performance without GRC is better; however, proposed controller still ensures finite time convergence of change in frequency under GRC and governor deadband. Proposed controller also guarantees finite time convergence of change in frequency under random varying load disturbances. We have also integrated renewable energy resources in the system and tried to handle relevant output power uncertainty in load frequency problem.