A Novel Voltage Balancing Method of Modular Multilevel Converters

Zunfang Chu, Zixin Li, Ping Wang, Yaohua Li

Key Laboratory of Power Electronics and Electric Drive, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing, China.

DOI: 10.4236/epe.2013.54B222                

Abstract

In this paper, a novel voltage balancing method of modular multilevel converters (MMCs) is proposed. This method divides the voltages of sub-module capacitors in each arm into several groups and the voltage balancing is based on these groups. The proposed method can save sorting time greatly compared with the conventional method. Simulation results on a MMC based three-phase inverter show validity of the proposed method.

 

Keywords

Modular Multilevel Converter; Voltage Balancing

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	A. Lesnicar and R. Marquardt, “An Innovative Modular Multilevel Converter Topology Suitable for a Wide Power Range,” in Power Tech Conference Proceedings, 2003 IEEE Bologna, Vol. 3, 2003, p. 6.
[2]	M. Hagiwara and H. Akagi, “PWM Control and Experiment of Modular Multilevel Converters,” in Power Electronics Specialists Conference, PESC 2008, IEEE, 2008, pp. 154-161.
[3]	M. Hagiwara and H. Akagi, “Control and Experiment of Pulsewidth-Modulated Modular Multilevel Converters,” Power Electronics, IEEE Transactions on, Vol. 24, 2009, pp. 1737-1746. doi:10.1109/TPEL.2009.2014236
[4]	S. Rohner, et al., “Pulse Width Modulation Scheme for the Modular Multilevel Converter,” in Power Electronics and Applications, EPE '09. 13th European Conference on, 2009, pp. 1-10.
[5]	S. Rohner, et al., “Modulation, Losses, and Semiconductor Requirements of Modular Multilevel Converters,” Industrial Electronics, IEEE Transactions on, Vol. 57, 2010, pp. 2633-2642.
[6]	T. Qingrui, et al., “Reduced Switching-Frequency Modulation and Circulating Current Suppression for Modular Multilevel Converters,” Power Delivery, IEEE Transactions on, Vol. 26, 2011, pp. 2009-2017. doi:10.1109/TPWRD.2011.2115258
[7]	Z. Li, et al., “An Improved Pulse Width Modulation Method for Chopper-Cell Based Modular Multilevel Converters,” Power Electronics, IEEE Transactions on, 2012, p. 1.
[8]	N. Flourentzou and V. G. Agelidis, “Multimodule HVDC System Using SHE-PWM With DC Capacitor Voltage Equalization,” Power Delivery, IEEE Transactions on, Vol. 27, pp. 79-86, 2012. doi:10.1109/TPWRD.2011.2167989