AGENERALIZED SPACE VECTOR MODULATION FOR CASCADED H-BRDGE MULTI-LEVEL INVERTER

Abstract

Nowadays, Space Vector Modulation (SVM) technique is widely used in multilevel converters with a variety of advantages: better utilization of DC bus in
comparison with Sin PWM and the lower harmonics, providing more space vectors
than the conventional two-level inverter. Consequently, we can enhance the quality
of multi-level converters.However, as the number of required converter levels rise,
the complexity and computation volume in the determination of optimized
switching sequence will increase. As a result, we have some difficulties in
implementing simulations and experiments. The paper provides a general SVM
technique which generates any level with cascaded H-bridge (CHB) structure so as to
not only simplify SVM techniques and reduce calculation volume but also create
favorable conditions to apply more widely this structure in industries. The proposed
method has been simulated in Matlab software and experimented with the 11-level
CHB structure based on FPGA platform, indicating the accuracy of the given method.