Robust digital control for boost DC-DC converter

If the duty ratio, load resistance and input voltage in boost DC-DC converter are changed, the dynamic characteristics is varied greatly, that is, boost DC-DC converter has non-linear characteristics. In many applications of DC-DC converters, the load cannot be specified in advance, and it will be changed suddenly from no load to full load. In the boost DC-DC converter system used a conventional single controller cannot be adapted to change dynamics and it occurs large output voltage variation. In this paper, the robust digital controller for suppress the change of step response characteristics and variation of output voltage in the load sudden changes is proposed. Experimental studies using micro-processor for controller demonstrate that this type of digital controller is effective to suppress variations.