Abstract：The unbalance of neutral point voltage is the inherent shortcoming of T-type inverter. The neutral point voltage offset models of space vector pulse width modulation (SVPWM) algorithm and virtual space vector pulse width modulation (VSVPWM) algorithm are established respectively. The relationship of the unbalanced region of neutral point voltage with the load power factor angle and modulation ratio is obtained. A full range accurate balance algorithm of neutral point voltage is proposed. In this algorithm, the precise balance of neutral point voltage is achieved by calculating and correcting the balance factor of the time of positive small vector. The algorithm is selected by judging the balance factor to reduce harmonics and switching losses effectively while maintaining accurate balance of neutral point voltage. Simulation and experimental results verify the proposed algorithm.
李敏裕, 马晓军, 魏曙光, 张杰. T型逆变器中点电压全范围精确平衡研究[J]. 电工技术学报, 2018, 33(8): 1814-1826.
Li Minyu, Ma Xiaojun, Wei Shuguang, Zhang Jie. Research on Full Range Accurate Balance of Neutral Point Voltage for T-Type Inverter. Transactions of China Electrotechnical Society, 2018, 33(8): 1814-1826.
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2018, Vol. 33 
