The Age of Multilevel Converters Arrives

This work is devoted to review and analyze the most relevant characteristics of multilevel converters, to motivate possible solutions, and to show that we are in a decisive instant in which energy companies have to bet on these converters as a good solution compared with classic two-level converters. This article presents a brief overview of the actual applications of multilevel converters and provides an introduction of the modeling techniques and the most common modulation strategies. It also addresses the operational and technological issues

Adaptive phase-shifted PWM for multilevel cascaded H-bridge converters with large number of power cells

Article number 7915210Cascaded H-bridge multilevel converters are usually applied for high-power systems with independent dc sources. It can be used as PV inverter or to operate independent battery stacks. In these cases, as each dc source can be working at different operational points, conventional modulators lead to high distorted output waveforms degrading the converter performance. In this paper, a modulation method as a modified version of conventional phase-shifted PWM is presented when the CHB converter has a large number of power cells. This method is an extension of a previous technique only suitable for CHB converters with three power cells per phase. Simulation results show the good performance of the proposal with higher number of cells.Qatar National Research Fund NPRP9-310-2-134Junta de Andalucía P11- TIC-7070Ministerio de Educación y Ciencia de España TEC2016-78430-RMinisterio de Educación y Ciencia de España 115142