Improved digital average current control of buck converter with dual-edge modulation

This paper explores digital average current (DAC) control buck converter with dual-edge modulation (trailing-triangle modulation and leading-triangle modulation). It is found that DAC control with dual-edge modulation doesn’t have sub-oscillation problems. As the same as conventional digital control of switching dc-dc converter, there is also one switching cycle time delay between sampling and corresponding duty ratio updating in DAC control algorithm. To overcome this time delay of DAC control, an improved digital average current (IDAC) control is then proposed and studied. The control laws of the proposed digital algorithms are discussed and compared. Simulation results are given to further verify the analysis results.