Biography
Enrollment Date: 2012
Graduation Date：2015
Degree：M.S.
Defense Date：2015.06.03
Advisors：Xiang Xie
Department：Institute of Microelectronics，Tsinghua University
Title of Dissertation/Thesis：Research on the Key Circuits of Wireless Power Receiver
Abstract:
With continuous development of technologies in design of integrated circuit design and manufacturing processes, Wireless power transfer technology has been used in the field of implantable biomedical and electronic products. This paper studies the design of wireless power receiver circuits under short-range background, the main innovations include:
1） Review of the basic principles of inductive coupling, extracting the basic model of wireless power receiver. According to environments and requirements of the two applications, design the architecture of wireless power receiver of wireless endoscopy and the smart card with wireless charging. Architecture design, including module division, interface requirements, performance parameters.
2）Optimize of the receiving antenna. The wireless capsule endoscopy moves freely in the human gastrointestinal tract, Thus three orthogonally receiving coils are used to ensure power receiving under arbitrary relative postures. Through modeling and analyzing of receiving antenna, the power received by three orthogonal receiving coils can be combined automatically by using the receiving circuit topology. In smart IC card, the receiving antennas contain signal antenna and power antenna. Based on the inductive coupling between the two receiving antennas, optimizing the received power by the power and signal antennas, at the same time, reducing the impact of the power antenna on the data transmission.
3）Study the power converter circuits, including the NMOS full-bridge rectifier, which the rectifier efficiency is up to 96%. And the bandwidth of rectifier used in smart IC card reaches 50MHz. In addition, study the new regulator circuit ‘Rectigulator’, which integrates the rectification and regulation functions. ‘Rectigulator’ not only improves the integration, and the conversion efficiency reaches 94 %.
4）Wireless energy management circuits used in smart IC card are proposed. Using constant current - constant voltage charging strategy, modify the control loop, make it suitable for the intermittent emission energy situation , automatically adjusts the charging state , complete the charging function correctly .
This paper completes two wireless power receivers of the wireless endoscope and smart IC card. And the circuits design can be a reference for other wireless power receiver.