Manjrekar M D, Lipo T A. A hybrid multilevel inverter topology for drive applications [C]. Applied Power Electronics Conference and Exposition, 1998: 523-529.
Kou Xiaomin, Corzine Keith A, Wielebski Mike W. Overdistention operation of cascaded multilevel inverters[J]. IEEE Transactions on Industry Applica- tions, 2006, 42(3): 817-824.
[5]
Sergio Busquets Monge, Bordonau J, Boroyevich D, et al. The nearest three virtual space vector PWM-a modulation for the comprehensive neutral-point balancing in the three-level NPC inverter[J]. IEEE Power Electronics Letters, 2004, 2(1): 11-15.
[6]
Lu Shuai, Corzine K A. Cascaded multilevel converters with non-integer or dynamically changing DC voltage ratios[C]. Power Electronics and Motion Control Conference, 2006: 642-647.