Experimental validation of a nested control system to balance the cell capacitor voltages in hybrid MMCs
Author
dc.contributor.author
Donoso Cisternas, Sergio Felipe
Author
dc.contributor.author
Cárdenas Dobson, Jesús Roberto Pedro Alejandro
Author
dc.contributor.author
Espinoza, Mauricio
Author
dc.contributor.author
Clare, Jon
Author
dc.contributor.author
Mora, Andrés
Author
dc.contributor.author
Watson, Alan
Admission date
dc.date.accessioned
2021-11-24T20:00:50Z
Available date
dc.date.available
2021-11-24T20:00:50Z
Publication date
dc.date.issued
2021
Cita de ítem
dc.identifier.citation
IEEE Access 9 (2021) 3054340
es_ES
Identifier
dc.identifier.other
10.1109/ACCESS.2021.3054340
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/182869
Abstract
dc.description.abstract
In a hybrid modular multilevel converter (MMC), capacitor voltage balance between the Full-Bridge Sub-Modules (FBSMs) and Half-Bridge Sub-Modules (HBSMs) is only possible when the arm currents are bipolar. For a grid-connected MMC, operating at unity power factor, this is typically only achievable when the modulation index is less than 2. Previous control methodologies, based on open-loop feed-forward compensating currents, have been proposed to operate an MMC with a higher modulation index. However, these solutions do not minimize the compensating currents; they cannot compensate entirely for both the variations in the operating conditions and the parameters typically encountered in a real implementation; and they do not consider the actual capacitor voltage imbalance between the FBSM and HBSMs. In this paper, a new nested closed-loop control algorithm based on an outer voltage control loop with an inner current loop is proposed and experimentally validated. Feed-forward currents are still utilised in the inner loop, but they are calculated using a new optimising algorithm which minimises the required compensating currents. Moreover, to the best of our knowledge, this is the first work where explicit algebraic equations to calculate these compensating currents are provided. Experimental results to validate the approach, obtained with an 18-cell hybrid MMC, are presented and discussed in the paper.
es_ES
Patrocinador
dc.description.sponsorship
CONICYT-PCHA/Doctorado Nacional/2016 21160931
Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)
CONICYT PIA/BASAL FB0008
Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT)
CONICYT FONDECYT 11190852
Fondect 1180879
es_ES
Lenguage
dc.language.iso
en
es_ES
Publisher
dc.publisher
IEEE
es_ES
Type of license
dc.rights
Attribution-NonCommercial-NoDerivs 3.0 United States