Multilevel power converters

Abstract

This chapter demonstrates the state of the art of multilevel power converter technology, discussing fundamental multilevel converter structures and modulation paradigms. A multilevel converter not only achieves high power ratings but also enables the use of renewable energy sources. A multilevel converter has several advantages over a conventional two-level converter that uses high switching frequency pulse width modulation (PWM). Multilevel converters produce smaller CM voltage and can draw input current with low distortion. Existing multilevel converters such as diode-clamped and capacitor-clamped multilevel converters can be derived from the generalized converter topology called P2 topology. To reduce the number of separate dc sources for high-voltage, high-power applications with multilevel converters, diode clamped or capacitor-clamped converters can be used to replace the full-bridge cell in a cascaded converter. Two multilevel converters can be connected in a back-to-back arrangement, and then the combination can be connected to the electrical system in a series-parallel arrangement. © 2011 Elsevier Inc. All rights reserved.