Robust control for buck voltage converter under resistive and inductive varying load

Voltage converter circuits are fundamental components in power electronics applications. However, their paramount role on various appliances due to their well-known benefits comes together with difficulties and restrictions for their modeling and control. A buck converter is naturally subjected to non-linearities, time-dependency, noise, and parameter variations. Altogether, it is difficult to provide a fully-descriptive model so linear approximations are commonly used, delegating those burdens to dependable controllers. Traditional models (and resulting controllers) are derived considering a simple resistance as converter's load. A non-resistive load actually requires the converter's model to be modified, many works have dealt only with resistive loads for sake of simplicity. As this behavior is seldom seen in real applications, this work focuses on a resistive-inductive varying loads. The robust controller design is able to face load variations, so cascaded or hierarchical approaches are avoided, resulting in a low-order single-loop controller. Proposal validation is provided through simulation tests over the actual circuit components' models, incorporated in Simulink's Simscape™ library.