A Generalized Space Vector Modulation for Cascaded H-bridge Multi-level Inverter

Nowadays, Space Vector Modulation (SVM) technique is widely used in multi-level 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.