A Comparison Between Three- and Four-Coil Wireless Power Transfer Systems with Resonant Coils





four-coil, power transfer efficiency, three-coil, wireless power transfer systems


In this paper, it is demonstrated that the efficiency and ability to transfer power to the load in three-coil wireless power transfer (WPT) systems are always higher than in equivalent four-coil ones. On the other hand, it is shown that there are features attainable in four-coil WPT system that are not in three-coil ones. For instance, in a four-coil WPT system, which can be divided into source, two communication, and load circuits, it is possible to devise a method for which the maximum power transferred to the load circuit or the maximum efficiency do not depend on the mutual inductance between the two communication coils, independently of the load resistance value. The necessary conditions to achieve the above feature together with the overall circuit analysis are discussed in details and practical results presented.

Author Biographies

F. B. de Moraes, Federal University of Technology – Paraná

FÁBIO B. DE MORAES received B.Eng. degree in Electrical Engineering from Catholic University of Pelotas (1996) and M.S. degree in Electrical Engineering Federal University of Technology-Parana (2013). He is currently professor in the Federal University of Technology - Paraná (UTFPR) - Campus Pato Branco and
doctoral student at Graduate School of Electrical Engineering and Computer Science (CPGEI) at UTFPR, Campus Curitiba. His research is focused on biomedical instrumentation, medical devices and electromagnetic compatibility.

P. J. Abatti, Federal University of Technology-Paraná

PAULO J. ABATTI received B.Eng. degree in Electrical Engineering from Federal University of Technology - Parana (UTFPR), licentiate degree in Special Disciplines - Electronics in 1980 and 1986, respectively, M.S. degree in Electrical Engineering from the University of Campinas (1983) and D.S. degree in Biomedical/Electronic Engineering - Tokyo Institute of Technology (1991). He is currently Full professor with the Federal University of Technology - Paraná (UTFPR) where he holds the office of Research Director of the Dean for Research and Graduate Studies. He held several administrative positions, including the post of Adjunct Provost of Research and Graduate Studies. In these positions, he was responsible for the institutional program of scientific and technological initiation, for the management/coordination of CT- INFRA institution’s program for the Research Ethics Committee and the Ethics Committee on Animal Use implementation, among others. In the science and technology area has experience in the field of Biomedical Engineering, with emphasis on Dental Instrumentation and Medical Hospital, mainly in developing passive biotelemetry techniques.


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How to Cite

Moraes, F. B. de, & Abatti, P. J. (2021). A Comparison Between Three- and Four-Coil Wireless Power Transfer Systems with Resonant Coils. Journal of Microwaves, Optoelectronics and Electromagnetic Applications (JMOe), 20(1), 208–218. https://doi.org/10.1590/2179-10742021v20i1924



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