Multilevel cascaded H-bridge (CHB) converters are an attractive solution for multiple applications like flexible ac transmission systems and solid-state smart transformers, among others. This article is focused on a CHB working with unbalanced conditions per cell (different cell dc voltages and/or cell voltage references). In this scenario, the phase-shifted pulsewidth modulation (PS-PWM) technique produces a harmonic distortion around twice the carrier frequency and its multiples in the CHB output voltage. In this article, a generalized variable-angle PS-PWM method is presented in order to mitigate this drawback improving the CHB output voltage harmonic spectrum. The proposed method is based on applying a mathematical search algorithm to determine the phase displacement angles to be applied to the PS-PWM technique. Experimental results show how this objective is achieved without introducing any disadvantage in the CHB operation. The method can be applied to CHB with any number of cells.
Generalized Harmonic Control for CHB Converters with Unbalanced Cells Operation / Marquez, Abraham; Leon, Jose I.; Monopoli, Vito Giuseppe; Vazquez, Sergio; Liserre, Marco; Franquelo, Leopoldo G.. - In: IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS. - ISSN 0278-0046. - STAMPA. - 67:11(2020), pp. 8924936.9039-8924936.9047. [10.1109/TIE.2019.2956383]
Generalized Harmonic Control for CHB Converters with Unbalanced Cells Operation
Vito Giuseppe Monopoli;
2020-01-01
Abstract
Multilevel cascaded H-bridge (CHB) converters are an attractive solution for multiple applications like flexible ac transmission systems and solid-state smart transformers, among others. This article is focused on a CHB working with unbalanced conditions per cell (different cell dc voltages and/or cell voltage references). In this scenario, the phase-shifted pulsewidth modulation (PS-PWM) technique produces a harmonic distortion around twice the carrier frequency and its multiples in the CHB output voltage. In this article, a generalized variable-angle PS-PWM method is presented in order to mitigate this drawback improving the CHB output voltage harmonic spectrum. The proposed method is based on applying a mathematical search algorithm to determine the phase displacement angles to be applied to the PS-PWM technique. Experimental results show how this objective is achieved without introducing any disadvantage in the CHB operation. The method can be applied to CHB with any number of cells.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
