Design and experiment of wireless power transfer systems via electromagnetic field near-zone region

ABSTRACT

This paper presents the fundamental principle, circuit implementation and measurement of wireless power transfer (WPT) technology through both Colpitts and Hartley oscillation prototype circuits. The Colpitts and Hartley oscillation prototypes are used to convert DC voltages into AC ones. Meanwhile, both half- and full-wave rectification circuits are designed correspondingly for AC/DC voltage conversion. In addition, the orientation and distance effects between the transmitting and receiving coils are investigated. The self-inductance, mutual-inductance and coupling coefficient for the coupled inductors are extracted as a function of distance and frequency by using an equivalent T-circuit network and a derived Z-parameter matrix. The proposed WPT systems operate at around 3.6 MHz and the transferred voltage is measured at the WPT receiving terminal. The measured results indicate that the two proposed WPT systems can operate properly for potential short-distance applications.

KEYWORDS:

• Wireless power transfer
• oscillation circuit
• magnetic inductive coupling
• mutual-inductance
• Z-parameter matrix

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was partially supported by Jiangsu innovation program for graduate education [grant number cxzz13_0164]; open research program in state key laboratory of millimeter waves [grant number k201304]; natural science foundation of china [grant number 61172024], [grant number 61171039].