Abstract：The neutral point voltage balancing problem is the inherent problem of the diode clamped three-level inverter. A detail discussion is presented in this paper. The causes of the unbalancing neutral point voltage are analyzed,and the impact on the neutral point potential of the carrier#x02019;s amplitude is studied. The relationship among neutral point voltage variation,modulation index,power factor,and regulation coefficient is investigated in detail,and the influence of the regulation coefficient and power factor on neutral point voltage variation is discussed. Then an amplitude-scaled SPWM modulation scheme is proposed,and the neutral point voltage is controlled balance by changing the amplitude of carriers without changing the modulation waves. The validity of the modulation scheme is verified on the DSP-based diode clamped three-level inverter platform.
龚博，程善美，秦忆. 基于载波的三电平中点电压平衡控制策略[J]. 电工技术学报, 2013, 28(7): 172-177.
Gong Bo,Cheng Shanmei,Qin Yi. A Three-Level Neutral Point Voltage Balance Control Strategy Based on Carriers of SPWM. Transactions of China Electrotechnical Society, 2013, 28(7): 172-177.
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