Robust control of current-mode controlled converters

A robust controller for multimodule current-mode push-pull power converters is presented. First, the small-signal equivalent circuit and transfer function model of the converter system are found. Then the slope compensation is selected and model reduction is performed using the concept of dominant energy mode. Based on the reduced converter models, a PI (proportional-integral) controller is quantitatively and systematically designed to the prescribed specifications. A robust controller is proposed and augmented to improve the control performance when parameter variations caused by system configuration change and by operating point shift occur. The performance of the converter and the effectiveness of the proposed controller are demonstrated by simulated and experimental results