Small-Signal Modeling of I2 Average Current Mode Control

摘要

average current mode control is a promising control technique featuring fast dynamic response, cycle-by-cycle current limiting and accurate current control. It can be treated as peak current mode control with no peak-to-average error. By combining direct current feedback and average current feedback, average current mode control is a three-loop control system. Since it is a new control technique proposed in 2013, few papers exist which discuss the small-signal model for this control method. In this paper, a small-signal model for constant frequency average current mode control is proposed which successfully predicts the subharmonics oscillation when the duty cycle is close to or greater than 0.5. The characteristics of average current mode control are also compared with average current mode control and peak current mode control to show its advantages.