Highly Efficient WPT System With Negative Impedance Converter for Q-factor Improvement

IEEE Access

Tae-Hyung Kim¹  Jong-Gwan Yook¹  Gi-Ho Yun²  Woongyong Lee³ 

[1] Department of Electrical and Electronics Engineering, Yonsei University, Seoul, South Korea;Department of Information and Communication Engineering, Sungkyul University, Anyang, South Korea;Department of Material Research and Development and Production, Amotech Company Ltd., Incheon, South Korea;

关键词: High efficiency;    negative impedance converter;    non-foster circuit;    Q-factor improvement;    wireless power transfer system;   

DOI  :  10.1109/ACCESS.2019.2933004

来源: DOAJ

【 摘 要 】

A negative impedance converter (NIC) has been combined with a wireless power transfer (WPT) system to maximize the system efficiency based on non-foster theory. The NIC is composed of transistor, voltage divider, capacitor, and inductor for impedance matching, and resonant circuit operating at 6.78 MHz. The desired negative impedance can be controlled by tunable impedance in the NIC. In this paper, the loss of the transmitting coil is reduced to 0.1 Ω, yielding a quality factor of 7,050, which is 19.1 times higher than that of the conventional coil. The WPT system with the NIC provides high power transfer efficiency (PTE) at various transmission distances. The experimental results are improved from 64% to 96% and from 5% to 55% at the transmission distances of 50 and 200 mm, respectively. Furthermore, the PTE is enhanced from 38% to 87% and from 2% to 38% at the diagonal misalignment distance of 0 and 150 mm, respectively, at a transmission distance of 100 mm. The proposed technology for increasing the receiving power in the receiving coil with a higher PTE can be utilized for numerous applications in the industrial, scientific, and medical band, with a restricted radio frequency power on the transmitter side.

【 授权许可】

Unknown