Control of Bifurcation in Current-Programmed DC/DC Converters: An Alternative Viewpoint of Ramp Compensation

A bstract |This paper reexamines the conventional currentmode control strategy as applied to dc/dc converters in the ligh t of \avoiding bifurcation". This alternativ eviewpoint permits convenien t selection of parameter values to guarantee stable operation. Slope compensation is viewed as a means to k eep the system suÆciently remote from the rst bifurcation point. It is shown that excessiv e bifurcation clearance is accompanied by undesirably slow dynamical response. A variable ramp compensation is proposed to dynamically adjust the slope magnitude such that the system is kept clear of bifurcation yet responding suÆciently fast during transients. The results ha vebeen con rmed by experimental measurements.