Design-Oriented Dynamical Analysis of Single-Phase H-Bridge Inverter

This paper reports the slow- and fast-timescale instabilities of a single-phase voltage-mode controlled H-bridge inverter. A comprehensive view and derivation of different dynamical regimes, stability boundary, stable and different types of unstable zones existing in power and control-circuit parameter spaces are obtained through Filippov's method facilitating selection of parameters for avoiding undesirable and unstable behaviors. Fast-timescale instability manifests as a localized period-doubling bifurcation gradually spreading through the whole line cycle with increasing bifurcation parameter values. Critical phase angles at which this develop are determined by Filippov's method. Slow-scale Hopf-bifurcation through border-collision resulting in large THD has also been witnessed. Bifurcation diagrams have been plotted to give a panoramic view of various dynamical behaviors at switching frequency.