Research On Control Strategy Of Single Inductor Multi Output Switching Power Supply

When using portable electronic equipment, people always want the equipment to have a long working time, which puts forward higher requirements for equipment power management. Many portable electronic devices have the characteristics of power supply with different levels of voltage. The proposed topology of single inductor multi output (Simo) converter improves the conversion efficiency of multi-channel output power supply used in portable devices. However, when the single inductor converter works in the current continuous mode, there is serious cross regulation between the output branches, which makes the output voltage unstable. In this paper, the single inductor dual output (SIDO) buck converter is taken as the research object, the working principle and different working modes are analyzed, the small signal model of the converter is established, and the essential reason of cross regulation is analyzed. On this basis, a complete closed-loop system model of PCM control is established, but the slope compensation in current control is difficult to design due to the different modes of inductive current. In this paper, another one cycle control without current loop is studied to stabilize the output of SIDO buck converter, and the closed-loop system model of one cycle control is established. The feasibility of single cycle control SIDO buck converter is verified by simulation and experiment.