说明：  To give an overview of bifurcations in DC/DC converters Two types of bifurcation found previously Fast-scale bifurcation (period-doubling): inner loop instability Slow-scale bifurcation (Hopf): outer loop instability Would they happen in practice? Are these phenomena interested only by circuit theorists? Can these studies be made relevant to the engineers? Case study of interacting fast and slow-scale bifurcation Can the two bifurcations happen simultaneously?Design-oriented analysis: We will show the operating boundaries in parameter space of various regions including stable, slow-scale unstable, fast-scale unstable and slow-fast-mixed unstable regions