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

 

ABSTRACT:

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.

 KEYWORDS:

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

 SOFTWARE: MATLAB/SIMULINK

 BLOCK DIAGRAM:

Fig.1.Types of multilevel converters.

Fig .2.Classification of multilevel modulations.

 EXPECTED SIMULATION RESULTS:

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

CONCLUSION:

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.

REFERENCES:

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[4] P. M. Bhagwat and V. R. Stefanovic, ―Generalized structure of a multilevel PWM inverter,‖ IEEE Trans. Ind. Applicat., vol. IA-19, pp. 1057–1069, Nov./Dec. 1983.

[5] G. Sinha and T. A. Lipo, ―A four level rectifier-inverter system for drive applications,‖ IEEE Trans. Ind. Applicat., vol. 30, pp. 938–944, July/Aug. 1994.