Large signal stability analysis of a DC/AC droop controlled inverter connected to an infinite bus

The large signal stability of a dc/ac inverter connected to an infinite bus is explored. The study aims to understand if a droop controlled inverter can lose synchronism with an infinite bus. Specifically, the analysis is completed using Lyapunov-based mathematical techniques. The 13th order mathematical model of a droop controlled inverter connected to an infinite bus is generated. An algorithm is used to estimate the domain of asymptotic attraction of the system. The effect of system parameters on the domain of attraction are explored. Moreover, the effect of control parameters are studied. Results suggest that a droop controlled inverter requires a long fault time or large transient to lose synchronism with the infinite bus. Numerical results validated the estimated domain of attraction.