Bidirectional wireless power/data transfer via magnetic field

Abstract

Recently, inductive power transfer (IPT) system has been used for wireless charging of electric vehicles (EVs). However, most of them only treat the issue of single directional wireless power transfer (WPT). This research proposes a novel bi-directional IPT (BD-IPT) scheme EVs, which can simultaneously transmit power/data via magnetic field when the mutual inductance changes. For power transmission, resonant inverters with phase-shift pulse width modulation (PSPWM) are used to generate carrier waves and alternating current. As for data transmission, a dedicated communication method with the accompanied protocol is proposed. Binary phase shift keying (BPSK) is used to simulate the two-quadrature amplitude modulation (QAM), which generates digital signals for data transmission without the need of extra communication links. Hamming codes are combined with single-error correction and double-error detection (SECDED) to ensure communication quality.