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Schematic of the CHB topology. The figure also shows the nomenclature considered in this paper, including the sign criteria and the ordering of the subscripts.
Source publication
This paper presents a method for switching reduction in cascaded H-bridge converters. Given the wide applicability of this topology, it would be especially desirable to increase its efficiency with switching losses reduction techniques. Since this type of converter requires voltage balancing methods, several modulation methods consider the possibil...
Contexts in source publication
Context 1
... its introduction to the present day, researchers have paid special attention to the development of multilevel converters, with the aim of allowing the industry to take advantage of the great number of features offered by multilevel topologies [1][2][3]. One of the most common multilevel converter topologies is the cascaded H-bridge converter (CHB), shown in Figure 1. Cascaded H-bridge converters play a relevant role in applications such as the integration of renewable energy [4][5][6][7], Synchronous Compensator (STATCOM) [8][9][10][11], power distribution applications [12,13] and railway traction systems [14,15]. ...
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... shown in Figure 1, a CHB comprises several modules in each phase. Each of these modules can produce any output voltage (U 11 , U 12 , U 21 . . . ...
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... origin of these transition commutations was illustrated using an example in which the CHB comprises only two modules per phase, as in Figure 1. For simplicity, in this example, all DC-links were considered to stay charged at 200 V, as if they were connected to external voltage sources. ...
Context 4
... i k be the current in phase k with the sign shown in Figure 1 (k ∈ {1, 2, 3}). Let V kj and U kj be the DC-link voltage and the output voltage of module j in phase k (j ∈ {1, 2 . . . ...
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Citations
... Of these, cascaded H-bridge (CHB) topologies have advantages over other MLI topologies (e.g., layout simplicity, extreme modularity, and construction and control simplicity) because they are free of voltage-balance issues. Moreover, compared to other MLI topologies, CHB topologies use the fewest components at the same voltage levels [3,4]. Asymmetrical CHB topologies have been proposed in which the DC voltages are not symmetrical. ...
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