A new DC side capacitance voltages balancing method for three-level inverters based on hybrid space vector modulation

作者：Fan Bishuang^*; Tan Guanzheng; Fan Shaosheng; Deng Zelin

来源：Proceedings of the CSEE, 2012, 32(27): 135-141.

• Capacitance voltage
• Control strategies
• DC side
• Neutral-point voltage balancing
• Space Vector Modulation
• Space vector modulations (SVM)
• Three-level inverters
• Three-level neutral point clamped
• Three-phase currents
• Time distribution
• Unbalancing problem
• Vector-based methods

Aiming at the DC side capacitance voltage unbalancing problem in the three-level neutral point clamped (NPC) inverters, a new neutral point voltage balancing method was proposed. In this method, each sector of the vector space had a unique control strategy. Different time distribution factors were set for different short vectors, which improved the neutral-point current control effect of the relative positive or negative short vector. In some sectors, the positive and negative vector pair don't take effect at the same time. Criterion was made according to the sign of three phase currents, which is transited between the traditional nearest three vectors method, and the virtual vector based method. Thus, the influence to the uncontrollable neutral-point current of medium vector was reduced. Simulation and experiment results are given to verify the correctness and validity of the proposed method.

• 出版日期2012
• 单位中南大学