Adaptive Nonlinear PID Controller for Boosted Load Frequency Management of Grids With Renewables and Energy Storage Units

ABSTRACT Power inconsistency between generation and demand causes to swing the frequency and tie‐line power across the grid. Power‐frequency swings undermine the reliability, security and stability of the grid, and may even cause power blackouts. The employment of an effective controller within load frequency management loop is therefore an inevitable necessity. An adaptive nonlinear PID (ANPID) controller enjoying interesting abilities is proposed in this article. Two nonlinear gains based on configurable hyperbolic functions of the error and the rate‐of‐error are utilized in cascade with the classical PID controller. The nonlinear characteristics of these gains make it possible to obtain a fast yet non‐oscillatory response without excessive overshoots. Further, through a mathematical framework, it is revealed that the ANPID controller is equivalent to the PIDD 2 controller with adaptive gains. Gains of the ANPID controller are prolifically calibrated using stochastic fractal search (SFS) algorithm. Performance achieved is tested for various power grids and a practical speed servo system under different circumstances. Furthermore, a comprehensive comparison against the state‐of‐the‐art is also established to appraise the literal contribution of SFS calibrated ANPID controller. The results affirm the supremacy of our proposal over previously published control architectures concerning minimum values of settling time/undershoot/error criterion of the frequency and tie‐line power swings.