Optimal control strategies for high-efficiency non-isolated DC-DC buck converters in IoT applications: A comparative study.

A DC-DC buck converter (DDBC) plays a crucial role in facilitating the rapid evolution of Internet of Things (IoT) applications across a broad spectrum of load requirements. Achieving high efficiency under diverse load conditions necessitates a meticulous exploration of modulation and control methods. This paper aims to explore literature concerning modulation and control techniques employed in buck converters for IoT applications, with the goal of achieving optimal efficiency. The most often used control methods in the DDBC for power conversion efficiently are adaptive controlled pulse skip modulation (APSM), pulse frequency modulation (PFM), digital pulse width modulation (DPWM), and adaptive on time control (AOT). Based on the major drawbacks of high quiescent current, large ripple, and low efficiency, the control methods used in IoT applications to achieve high efficiency are discussed. The structure of DDBC with the unique controlling method and their capability of suppressing the output ripple voltage and minimizing quiescent current are briefly addressed. Comparison among the methods exhibits how control methods can achieve high efficiency. This paper outlines the major challenges in power converter control for future research and development.