A Fast Space-Vector Modulation Algorithm for Multilevel Three-Phase Converters



This paper introduces a general space-vector modulation algorithm for -level three-phase converters. The algorithm is computationally extremely efficient and is independent of the number of converter levels. At the same time, it provides good insight into the operation of multilevel converters.


  1. Digital control
  2. Pulse width modulation
  3. Space vectors



Fig.1.Types of multilevel converters.

Fig .2.Classification of multilevel modulations.


 Fig.3.Normalized line-to-line PWM voltage waveforms for three, four and five-level converters.


This paper has presented a fast new SVM algorithm for multilevel three-phase converters. The algorithm is general and applicable to converters with any number of levels. In addition, the number of steps required to select the nearest three vectors and compute their duty cycles remains the same regardless of the number of converter levels or the location of the reference vector. In addition, the computational efficiency of this algorithm makes it a useful simulation tool for further study of the properties of multilevel converters.


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