HYBRID energy storage systems (HESSs) combine high-energy batteries with high-power ultracapacitors to achieve improved performance in electric vehicle (EV) applications. Multi-source inverters (MSIs) enable active energy management in HESSs, but conventional space vector modulation (SVM) often results in high switching frequency, excessive conduction losses, and uneven thermal stress on devices. This paper proposes an improved modulation scheme that introduces additional space vectors and partitions the voltage space into multiple regions, optimizing switching patterns to reduce switching frequency and losses. A comprehensive comparison with conventional SVM highlights enhancements in efficiency, thermal balance, and total harmonic distortion (THD). The proposed approach is validated through simulations. These results position the proposed modulation as a promising candidate for high-performance HESS-based EV systems.
