Study On Wireless Power And Data Transfer Technique Based On Frequency Division Multiplexing

As rapid development of the wireless power charging technology, the wireless power transfer has been received more and more attention in industrial applications such as wireless chargers and electrical vehicle charging stations. A well designed WPT system includes:high power density, high transmission efficiency, controllable output power and feedback mechanism. Since the primary side and secondary side lack a reliable near field wirelss communication mechanism, which is suitable for WPT system, and there are inadequate solutions for bidirectional power flow in WPT applications based on wireless power and data transmission technique. This paper focuses on following aspects for WPT systems:1. Based on fundamental two-coil WPT compensation topologies, this paper mainly studies voltage-fed compensation topologies including SS and SP structures, and their static working performance. Detailed aspects of this research involves the frequency splitting phenomenon, the relationship between the system performance and parasitic parameters of the inductive coil. The concluded circuit models are verified on a500W voltage-fed WPT platform.2. This paper also investigates near field wireless power and signal transmission technique which is a step further on previous works. In order to increase the data rate in high power WPT applications such as EVs, we propose a frequency division multiplexing based power and signal transmission technique. In this section, the influence of the communication unit toward power transmission channel are discussed at the beginning, and then the near field communication channel characteristics are studied under power transfer environment. Furthermore, the model of the NFC channel and the SNR in WPT system are also concluded using circuit parameters. At last, the effectiveness of the proposed method are tested on the500W prototype.3. With aforementioned wireless power and signal transmission techniques, this paper researches on the system performance of the symmetric and asymmetric compensation dual active bridge WPT converter. Moreover, the phase shift range, the output power and transmission efficiency that relates to parasitic resistance of the inductive coils are well discussed, and the theoretical models of the proposed DAB WPT converter are validated on a500W experimental test bed.