DC-DC power converter with a modified control scheme to improve load transient response

A modified control scheme is presented in this paper to improve the load transient response of DC-DC power converter by utilizing a previously proposed auxiliary circuit which is capable of operating in both boost mode to discharge the output capacitor during load step down transient, and in buck mode to charge the output capacitor during load step up transient. The proposed modified control scheme for the auxiliary circuit is based on the output voltage peak detection, preset thresholds and zero crossing time information. This scheme achieves significant improvement in load transient response while eliminating the controller performance sensitivity to component values tolerances and complex calculations that could result in undesired transient response. A simulation model is built in MATLAB^®/SIMULINK^® software package to validate the functionalities and advantages of the proposed control scheme.