**5. Conclusions**

In this paper, a novel RPWM selective harmonic elimination method for single-phase VSI is proposed. A new pulse position which is placed at the back of the switching cycle is provided for RPWM selective harmonic elimination method. By using that, it can remove harmonics with certain frequency from output voltage and current. In fact, this has been done using switching cycle determination by switching cycles in the previous cycle and duty ratio. Compared with the fixed

switching frequency SPWM and the traditional RPWM, the harmonics can be distributed uniformly in certain frequency range, and some unwanted harmonics can be eliminated successfully with the proposed method. A new pulse position for the RPWM selective harmonic elimination method is introduced in this paper, which is beneficial to improve the randomness of RPWM. When calculating *T*n+1, *D*n+<sup>1</sup> does not need to be calculated first. The random arrangemen<sup>t</sup> of the pulse position in switching cycle is worth studying in next steps.

**Author Contributions:** Conceptualization, G.L. and C.L.; methodology, Y.W.; software, Z.F.; validation, G.L. and C.L.; formal analysis, Y.W.; writing—original draft preparation, G.L.; writing—review and editing, C.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by National Natural Science Foundation of China, gran<sup>t</sup> number 51307076 and Natural Science Foundation of Liaoning Province, China, gran<sup>t</sup> number 20180550268.

**Acknowledgments:** The authors thank Liaoning Technical University for providing the support to enable this research to be carried out.

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