Investigation of Reflected Wave Phenomenon in SiC-based Two-Level Split-Phase Inverter-Fed Motor Drives

Abdul Basit Mirza, Kushan Choksi, Sama Salehi Vala, Ali Anwar and Fang Luo
IEEE Transactions on Power Electronics, 2025
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Abstract: Fast switching speed of Silicon Carbide (SiC) exacerbates Reflected Wave Phenomenon (RWP) in two-level (2L) Voltage Source Inverter (VSI)-based motor drives, causing motor side overvoltage and drive side overcurrent. The 2L split-phase (2L-SP) topology shows prospects of alleviating RWP due to its lower output dv/dt facilitated by split-inductors which also serve as an output reactor. This article explores RWP in a 2L-SP-based motor drive and compares it with the 2L with an output reactor, denoted as 2L-LF. For the study, a 2L, 2L-LF and 2L-SP configurable 18 kVA SiC-based prototype is developed and interfaced to an emulated motor load through a bundled shielded cable. At first, simplified lumped Differential Mode (DM) equivalent circuits are derived for modeling RWP transients in 2L-LF and 2L-SP drives. Subsequently, RWP is investigated through Double Pulse Tests (DPT) for various cable lengths, reactor (2L-LF), and split inductor (2L-SP) values. Results show that 2L-SP exhibits lower RWP for longer cables, achieving up to 68 % and 73 % reduction in overvoltage and overcurrent amplitudes for an 8 m cable. An anomalous rising overvoltage pattern for short cables is observed for both drive configurations and analyzed using proposed DM equivalent circuits. Further, from a switching performance standpoint, split-inductors in 2L-SP decouple load and complementary cell 's parasitics from the device during switching, achieving 17 % lower switching loss than 2L-LF. Following the DPTs, continuous three-phase tests are performed for 8 m cable for both drive configurations. The 2L-SP drive achieves up to 60 % and 74 % reduction in overvoltage and overcurrent amplitudes than 2L-LF. Overall, 2L-SP outperforms 2L-LF in mitigating RWP in SiC-based 2L VSI motor drives.

Recommended citation (BibTex):

@ARTICLE{MirzaRWP2025, 
 author={Mirza, Abdul Basit and Choksi, Kushan and Vala, Sama Salehi and Anwar, Ali and Luo, Fang}, 
 journal={IEEE Transactions on Power Electronics}, 
 title={Investigation of Reflected Wave Phenomenon in SiC-based Two-Level Split-Phase Inverter-Fed Motor Drives}, 
 year={2024}, 
 pages={1-19}, 
 doi={10.1109/TPEL.2024.3514096} 
}