Contents I. Introduction
Multilevel converters are usually associated with the handling of higher levels of power and voltages to overcome constraints of semiconductor availability and losses concerns over the traditional two or three level inverters [1], [2]. Among the most commonly used multilevel topologies are the modular multilevel converter (MMC), neutral-point-clamped (NPC), with clamping diode, flying capacitor, and cascaded H-bridge (CHB) [3]. Recently, multilevel converters have been receiving attention not only for these applications, but also for low-power converters, especially those powered by renewable sources such as photovoltaic panels or fuel cells [4]. In such cases, sources generally have lower voltage levels and usually require a series association to increase the voltage levels for grid connection. Multilevel converters, and especially the CHB depicted by Fig. 1, become important choices. Besides allowing to work with reduced individual voltage levels, modularity and the possibility of using individual maximum power point trackers are also aspects of interest for this type of converter [5], [6].
Single-phase cascaded H-hridge multilevel converter.
