Optimal Slope Compensation for step load in peak current controlled dc-dc Buck Converter

摘要

The paper comes up with the variation of slope compensation with step load and duty cycle for one cycle control in a peak current controlled dc-dc buck converter. For an optimal performance under varying load conditions and input voltage the amount of slope compensation desired, vary dynamically. A conventionally used linear slope is definitely not a solution. To meet the dynamic requirement of slope in a current controlled dc-dc buck converter a nonlinear ramp generator circuit has been proposed. The primary aim of the circuit is to provide a slope which is very small for low duty cycles and increases steeply as duty cycle increases. Consequently, it proves much more efficient in low duty cycle (less than 0.5) of operation. On the higher side this achieves a similar performance as that by a linear ramp with much less p-p value of the ramp.