Cross regulation is the main technical challenge of a single-inductor multiple-output (SIMO) dc–dc converter.
This project proposes amultivariable digital controller to suppress the cross regulation of a single-inductor dual-output (SIDO) buck converter in continuous conduction mode (CCM) operation. The controller design methodology originates from the open-loop shaping of the multi-inputmulti-output (MIMO) systems. The control design procedure includes: 1) determination of a family of nonparametric models of the SIDO converter at operating points of interest, 2) determination of the class of the controller, and 3) system open-loop shaping by the convexminimization of the summation of the square second norm of the errors between the system open-loop transfer function matrices and a desired open-loop transfer function matrix.
The proposed controller minimizes the coupling between the outputs of the SIDO converter and provides satisfactory dynamic performance in CCM operation.