A new digital control boundary current mode buck-boost DC-DC converter

The purpose of this paper is to present a new digital control boundary current mode buck-boost dc-dc converter. This buck boost dc-dc converter is intended for use as the low power converters, such as solar and wind power generation. The buck-boost dc-dc converter is widely used in the energy management field, because it has capability to obtain the wide input range characteristic. Moreover, the circuit configuration is very simple. However, it also has the disadvantage likely to be unstable system. On the other hand, the dc-dc converter that operates in a boundary current mode has the some advantages. This paper presents a consideration of the prediction error of the zero-cross point. In the proposed method, the current zero point of the inductor is predicted using the equations based on the nonlinear analysis of the output voltage and input voltage. The simulation results show that the zero-cross point detection error is attributed to the resolution error of the A-D converter and DPWM.