Study on impedance matching and maximum wireless power transfer efficiency of circuits with resonant coupling based on simplified S-matrix

In this manuscript, the simplified S-matrix of the pair of RLC circuits with resonant coupling at the resonant frequency is revealed. All of the elements of the S-matrix (S-parameters) are expressed by using essential quantities, which are the port-impedance / resistance ratios and the kQ-product. The matching condition and the maximum power transfer efficiency are analytically derived from the elements of the simplified Smatrix. key words: S-matrix, impedance matching, kQ-product, maximum efficiency Classification: Electromagnetic theory

[1]  Takashi Ohira.  Power transfer efficiency formulation for reciprocal and non-reciprocal linear passive two-port systems , 2018, IEICE Electron. Express.

[2]  Rongge Yan,et al.  Optimization of output power and transmission efficiency of magnetically coupled resonance wireless power transfer system , 2018 .

[3]  K. Kurokawa,et al.  Power Waves and the Scattering Matrix , 1965 .

[4]  Minoru Okada,et al.  kQ-product formula for multiple-transmitter inductive power transfer system , 2017, IEICE Electron. Express.

[5]  Ohira Takashi.  Trigonometric Phasor View on Magnetically Coupled Resonators for Wireless Power Transfer , 2016 .

[6]  Takashi Ohira.  How to estimate the coupling Q factor from two-port 5-parameters , 2017, 2017 IEEE International Conference on Computational Electromagnetics (ICCEM).

[7]  M. Kesler.  Highly Resonant Wireless Power Transfer: Safe, Efficient, and over Distance , 2013 .

[8]  M. Soljačić,et al.  Wireless Power Transfer via Strongly Coupled Magnetic Resonances , 2007, Science.

[9]  Chunting Chris Mi,et al.  Wireless Power Transfer for Electric Vehicle Applications , 2015, IEEE Journal of Emerging and Selected Topics in Power Electronics.

[10]  Heng-Ming Hsu,et al.  Wireless power transfer efficiency of variable load impedance , 2017, 2017 IEEE Wireless Power Transfer Conference (WPTC).

[11]  Ikuo Awai,et al.  Phenomenological and Essentialismic Theories of Coupling between Resonators , 2015 .

[12]  Tong Zhang,et al.  Efficiency and Optimal Loads Analysis for Multiple-Receiver Wireless Power Transfer Systems , 2015, IEEE Transactions on Microwave Theory and Techniques.

[13]  Takashi Ohira.  Maximum available efficiency formulation based on a black-box model of linear two-port power transfer systems , 2014, IEICE Electron. Express.

[14]  Takashi Ohira.  Power Transfer Theory on Linear Passive Two-Port Systems , 2018, IEICE Trans. Electron..

[15]  Gregory D. Durgin,et al.  Harvesting Wireless Power: Survey of Energy-Harvester Conversion Efficiency in Far-Field, Wireless Power Transfer Systems , 2014, IEEE Microwave Magazine.

[16]  William C. Brown,et al.  The History of Power Transmission by Radio Waves , 1984 .

[17]  Takashi Ohira,et al.  What in the World Is Q? [[Distinguished Microwave Lecture} , 2016, IEEE Microwave Magazine.

[18]  Takuichi Hirano.  Relationship between Q factor and complex resonant frequency: investigations using RLC series circuit , 2017, IEICE Electron. Express.

[19]  I. Awai,et al.  Transferred power and efficiency of a coupled-resonator WPT system , 2012, 2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications.