**6. Conclusions**

The configuration three-phase CHB-qSBI is presented in this paper. The three-phase CHB-qSBI can buck-boost voltage with single-stage power conversion. Furthermore, the three-phase CHB-qSBI immunized the ST phenomenon. In comparison to the three-phase CHB-qZSI, the CHB-qSBI dropped a large number of inductors and capacitors. The DC-link voltage of each module can achieve the same values by controlling the ST duty cycle. The paper describes the circuit analysis, operating theories, and PWM strategy of the introduced topology. Simulation and experimental results prove the validity of the improved PWM strategy for controlling the three-phase CHB-qSBI. The three-phase CHB-qSBI can be applicable.

**Author Contributions:** All authors contributed equally to this work and all authors have read and approved the final manuscript.

**Funding:** This research was funded by the Korea Institute of Energy Technology Evaluation and Planning (KETEP), and the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea gran<sup>t</sup> number 20184010201650 and the APC was funded by KETEP and MOTIE.

**Acknowledgments:** This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry and Energy (MOTIE) of the Republic of Korea (NO. 20184010201650).

**Conflicts of Interest:** The authors declare no conflict of interest.
