TY - GEN
T1 - Improving capacitor voltage ripples and power losses of modular multilevel converters through discontinuous modulation
AU - Picas, R.
AU - Ceballos, S.
AU - Pou, J.
AU - Zaragoza, J.
AU - Konstantinou, G.
AU - Agelidis, V. G.
PY - 2013
Y1 - 2013
N2 - The voltage ripple of the capacitors of the modular multilevel converter (MMC) increases when the converter output frequency decreases. This occurs in motor drive applications at low motor speeds, where the output frequency is reduced proportionally to the converter modulation index. In this paper, a discontinuous modulation technique for reducing the amplitude of the capacitor voltage ripples and the switching losses, especially at low modulation indices, is presented. The technique is based on adding a zero-sequence to the original modulation signals, clamping the MMC arms to the upper or lower rails of the fictitious dc-link bus. A current control strategy suitable for this modulation strategy is also proposed. Simulation results under various operating points are reported along with evaluation and comparison results against the conventional carrier-based pulse-width space-vector modulation.
AB - The voltage ripple of the capacitors of the modular multilevel converter (MMC) increases when the converter output frequency decreases. This occurs in motor drive applications at low motor speeds, where the output frequency is reduced proportionally to the converter modulation index. In this paper, a discontinuous modulation technique for reducing the amplitude of the capacitor voltage ripples and the switching losses, especially at low modulation indices, is presented. The technique is based on adding a zero-sequence to the original modulation signals, clamping the MMC arms to the upper or lower rails of the fictitious dc-link bus. A current control strategy suitable for this modulation strategy is also proposed. Simulation results under various operating points are reported along with evaluation and comparison results against the conventional carrier-based pulse-width space-vector modulation.
UR - https://www.scopus.com/pages/publications/84893615615
U2 - 10.1109/IECON.2013.6700160
DO - 10.1109/IECON.2013.6700160
M3 - Conference contribution
AN - SCOPUS:84893615615
SN - 9781479902248
T3 - IECON Proceedings (Industrial Electronics Conference)
SP - 6233
EP - 6238
BT - Proceedings, IECON 2013 - 39th Annual Conference of the IEEE Industrial Electronics Society
T2 - 39th Annual Conference of the IEEE Industrial Electronics Society, IECON 2013
Y2 - 10 November 2013 through 14 November 2013
ER -