Contactless power and bidirectional data transmission via magnetic field

Abstract

At present, the wireless charging and data transmission systems developed by major car manufacturers rely heavily on additional transmission equipment. This paper presents a newly developed wireless power and bidirectional data transmission scheme without adding any radio frequency (RF) devices. The battery charge status and vehicle related information can be transmitted bidirectionally in the wireless manner by the compensation capacitor between two isolated units. Based on the function, this system can quickly inform the user when an emergency event occurs during power transmission. An inverter is used on the primary side of the system, and the generated AC power is transmitted to the load at the secondary side through mutual inductance; the secondary side of the system adjusts the load current to transmit data back. The primary side uses the zero voltage switching (ZVS) method to receive data, and the trimming of the current curve to transmit commands; the secondary side of the system receives commands and uses carrier cycles for decoding. Experimental verification shows applicability of the proposed system.