TY - JOUR
T1 - Voltage-Balancing Method for Modular Multilevel Converters Switched at Grid Frequency
AU - Deng, Fujin
AU - Chen, Zhe
PY - 2015/5
Y1 - 2015/5
N2 - The modular multilevel converter (MMC) becomes attractive for high-voltage and high-power applications due to its high modularity, availability, and power quality. The voltage balance issue of capacitors is very important in the MMC, and the balancing of the capacitor voltage is increasingly difficult as the switching frequency is reduced. In this paper, a voltage-balancing method is proposed for the MMC switched at grid frequency with reduced losses and does not rely on the arm current. By assigning the low-frequency pulses with different pulse widths, the capacitor charge transfer in the MMC can be controlled for keeping the capacitor voltage balancing in the MMC. Simulations and experimental studies of the MMC are conducted, and the results confirm the effectiveness of the proposed capacitor voltage-balancing method.
AB - The modular multilevel converter (MMC) becomes attractive for high-voltage and high-power applications due to its high modularity, availability, and power quality. The voltage balance issue of capacitors is very important in the MMC, and the balancing of the capacitor voltage is increasingly difficult as the switching frequency is reduced. In this paper, a voltage-balancing method is proposed for the MMC switched at grid frequency with reduced losses and does not rely on the arm current. By assigning the low-frequency pulses with different pulse widths, the capacitor charge transfer in the MMC can be controlled for keeping the capacitor voltage balancing in the MMC. Simulations and experimental studies of the MMC are conducted, and the results confirm the effectiveness of the proposed capacitor voltage-balancing method.
KW - Capacitor voltage balancing
KW - Control strategy
KW - Modular multilevel converter (MMC)
KW - Modulation strategy
U2 - 10.1109/TIE.2014.2362881
DO - 10.1109/TIE.2014.2362881
M3 - Journal article
SN - 0278-0046
VL - 62
SP - 2835
EP - 2847
JO - I E E E Transactions on Industrial Electronics
JF - I E E E Transactions on Industrial Electronics
IS - 5
ER -