Abstract：The neutral voltage unbalanced problem is an inherent drawback for the application of diode clamped three-level converters. Based on the investigation into the double signal PWM method and the relationship between the average neutral current and neutral voltage, this paper proposes an algorithm of the compensator which can modified the neutral current and finally balance the neutral voltage. The compensator, which involves the load currents, switching frequency, capacitor value, neutral voltage, etc., is verified by simulation and experimental results that the dynamic process for neutral voltage balance is fast and the system is kept stable.
王琛琛, 张灿, 游小杰. 基于双调制波的中点电压平衡算法[J]. 电工技术学报, 2012, 27(3): 164-170.
Wang Chenchen, Zhang Can, You Xiaojie. A Neutral-Point Voltage Balancing Algorithm Based on Double Signal PWM Method. Transactions of China Electrotechnical Society, 2012, 27(3): 164-170.
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