Novel Multilevel Current Source Converter with Asymmetric Configuration: Analysis, Comparison, Modulation and FPGA Implementation

This paper proposes a novel asymmetric multilevel current source converter presented as a five-level converter but can be generalized for other levels. The proposed converter can generate the same current levels with fewer components than conventional symmetric multilevel current source converter, thus reducing the cost and complexity of the system. The paper also analyzes and compares the proposed converter with the conventional five-level topology regarding the number of components, semiconductors losses, harmonic distortion, and cost distribution. A modulation strategy based on space vector modulation is developed for the proposed converter to achieve DC-link balanced currents. Moreover, a field-programmable gate array (FPGA) based controller is designed and implemented to realize the modulation strategy and control the converter operation with a digital signal processor (DSP). Simulation and experimental results demonstrated the feasibility and performance of the proposed topology.