Stabilization And Dynamical Analysis Of V~2 Controlled Boost Converter

V~2 controlled switching converters have fast load transient response,conventional V~2control is peak V~2 control thus cannot be applied to boost converter.Peak V~2 control with inductor current compensation or valley V~2 control can be used to control boost converter.But there is stability issue like subharmonic oscillation when duty cycle of valley V~2controlled boost converter is small or ceramic capacitors with small capacitance constant are used as output capacitors.To investigate stabilization of V~2 controlled boost converter,discrete iterative models of peak V~2 controlled boost converter with inductor current compensation or hybrid ramp compensation are derived.Discrete iterative models of valley V~2 controlled boost converter with different ramp compensation are also derived,including inductor current compensation,external ramp compensation and hybrid ramp compensation.Baed on the models,the dynamical behaviors of converters are investigated with bifurcation diagrams and maximal Lyapunov exponents.The instability mechanisms are analyzed.According to stability boundary equations,operation regions are obtained to guide stabilization and parameter design for V~2 controlled boost converter.Firstly,the dynamical behaviors of V~2 controlled boost converter with inductor current compensation are investigated when inductor current sensing coefficient varies.With decreasing of inductor current sensing coefficient or input voltage,the orbit of peak V~2controlled boost converter with inductor current compensation enters into period-2 from period-1 by period-doubling bifurcation,and then to chaos by border-collision bifurcation.When valley V~2 controlled boost converter operates in chaos due to small equivalent series resistance of output capactors,by adding inductor current compensation,as inductor current sensing coefficient increases,the orbit of boost converter enters into multi-period,and finally is stabilized to period-1.The stable operation region of converter is broadened by applying inductor current compensation.Secondly,the stabilization of external ramp compensation on valley V~2 controlled boost converter is investigated.When converter operates in chaos due to small equivalent series resistance of output capactors or high input voltage,with increasing of equivalent external ramp slope,the converter enters into multi-period,and finally is stabilized to period-1.The stable operation region of converter is broadened by applying external ramp compensation.Thirdly,to stabilze the instability of peak V~2 controlled boost converter with inductor current compensation,external ramp compensation can be added to build hybrid ramp compensation.As external ramp slope increases,the converter is stabilized from chaos to period-2,then to period-1.In comparsion,peak V~2 controlled boost converter with hybrid ramp compensation has broader stable operation regions.Hybrid ramp compensation is applied to valley V~2 controlled boost converter,which enables boost converter to stably operate in wider parameter scopes.Finally,dynamical analysis is verified by PSIM simulations and experiments.