Summary: | Thesis (PhD)--University of Stellenbosch, 2004. === ENGLISH ABSTRACT: Multilevel converters were developed as a result of a growing need for higher power converters.
This dissertation addresses a specific multilevel topology called the multicell topology. A problem
associated with this topology is cell capacitor voltage unbalance. This dissertation addresses the issue
of natural balancing of multicell converters. The topology is mathematically analysed and a theory is
developed to explain the natural balancing mechanism. The study of the natural balancing property
includes a detailed harmonic-, steady-state- and time constant analysis. The theory is verified by a
comparison between the theoretical-, simulated- and experimental results. === AFRIKAANSE OPSOMMING: Veelvlakkige omsetters het ontstaan as gevolg van ’n behoefte aan ho¨er drywing omsetters. Hierdie proefskrif handel spesifiek oor die veelsellige omsetter topologie. ’n Probleem wat met hierdie topologie geassosieer word is selkapasitor onbalans. Hierdie proefskrif ondersoek die natuurlike balansering van veelsellige omsetters. Die topologie word wiskundig geanaliseer en ’n teorie word geformuleer om die natuurlike balanseringsmeganisme te verduidelik. Die ondersoek van die natuurlike balanseringseienskap bevat ’n volledige harmoniese-, bestendige toestand- en tydkonstante analise. Die teorie is gekontroleer deur teoretiese-, simulasie- en eksperimentele resultate te vergelyk.
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