Boundary between CCM and DCM in DC/DC PWM Converters
نویسنده
چکیده
It is presented a modality to compute the boundary between the discontinuous (DCM) and continuous (CCM) operating modes in the DC/DC fourth-order PWM converters with parasitic resistances. To reach this goal, an averaged model of the converter has been used. The boundary between DCM and CCM, considered to be the critical load resistance Rcrit, or, equivalently, the critical value of the inductor conduction parameter kctrit, is found as the positive root of a second-degree equation with unknown Rcrit or kctrit. The algorithm carried out and implemented with MATLAB environment allows studying the effect of the parasitic resistances and the coupling of inductors over the boundary Rcrit or ktcrit, the steady-state properties and the external characteristics of the converter. The simulation results show that the parasitic resistances and the inductor coupling change the boundary between the discontinuous and continuous conduction modes of a fourth-order PWM converter. Key-Words: DC/DC fourth-order PWM converters, boundary between CCM and DCM
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