Examining the Intermittency in the Swing Equation

Studying the nonlinear dynamical systems and their stability is important for various engineering applications, especially with power systems. While previous studies have examined primary, subharmonic resonances and quasiperiodicity in nonlinear systems, the phenomena of intermittency remain unfamiliar. This study analyses intermittency in the swing equation, which is a second-order differential equation that characterises the dynamic behaviour in power systems. Intermittency, modelled by sudden bursts within periodic regions, plays a vital role in the transition from stability to chaos. It also identifies the conditions under which intermittency occurs, mainly when varying the inertia and voltage of the machine. Numerical simulations, bifurcation diagrams, Poincar´e maps, heat maps and Lyapunov exponents are used to determine intermittency. Findings show that intermittency happens as a precursor to chaos, affecting the stability of the system. Results also indicate small disturbances can induce instability, thereby providing insights into the control aspect. It contributes to a broader understanding of the swing equation and highlights the importance of identifying the precursors to chaos to mitigate the adverse effects.