Abstract Since the neutral point potential fluctuation of three-level inverter is difficult to suppress under discontinuous modulation strategy, a dynamic space vector strategy was proposed. This strategy could generate a dynamic space vector by real-time detecting the upper and lower capacitor voltages, and then accurately synthesize the reference vector. This paper adopted gh coordinate system and parity sector conversion method to reduce the complexity of the dynamics algorithm. In order to eliminate the neutral point potential offset, this paper also proposed a method of switching vector sequence with reverse effect on the neutral point potential in real time. Finally, the evaluation method of modulation strategy based on the error current vector was given, which verified the advantages of the dynamic space vector modulation. Simulation and experimental results further show the effectiveness of the proposed method.
Zeng Jiang,Yang Lin,Huang Junchi等. Discontinuous Modulation of Three-Level Inverter Based on Dynamic Space Vector[J]. Transactions of China Electrotechnical Society, 2019, 34(2): 377-386.
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2019, Vol. 34 
