**4. Conclusions**

The periodic wireless power transfer system was investigated by using numerical and circuit analysis. The authors defined the methodology of creating a field model of the WPT system, combined with current sheet approximation of multi-turn coils. The equivalent electrical circuit model of the WPT cell was proposed, which is an alternative for complex numerical analysis or experimental research of physical prototypes. The proposed circuit model provides the ability to perform fast and simplified calculations of WPT cells with di fferent structures of coils. It is also possible to adjust electrical parameters of the system by utilizing the proposed models in order to design a periodic WPT structure with desired properties.

The introduced circuit model can replace the 3D field model, when analysis of periodic systems with many WPT cells is considered. The results indicated acceptable accordance of both models. Mean difference for computed variants of WPT system was 12.44%, with a standard deviation of 9.97%. This confirmed a possibility of estimating lumped parameters of the system by using the presented analytical formulas. A further analysis of WPT will focus on coils with various shapes and capacitive loads.

**Author Contributions:** The paper was written by A.S. The methodology and results presented in this paper were developed by A.S. and J.M.S. The analysis was performed by J.M.S. and A.C. The review, editing, and improvements to the content were made by A.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work was supported by the Ministry of Science and Higher Education in Poland, at the Białystok University of Technology, under research subsidy No. WZ/WE-IA/2/2020.

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