Design of Wireless Power Supply Optimized Structure for Capsule Endoscopes

  • Chang Cui Liaoning Shihua University
  • Qiang Zhao Liaoning Shihua University
  • Zhongjian Li University of Southern Queensland


Wireless power transmission is an important method for powering wireless capsule endoscopes, but its efficiency is low,especially when the devices move freely in random positions and orientations. To improve the stability and efficiency of theendoscope in vivo, this study designed an optimization method for planar spiral coils utilized in wireless power transfer forcapsule endoscopes. An optimized structure using six planar spiral coils was first proposed as the transmitting coil, and theefficiency of a series-parallel wireless power transmission model was analyzed. A theoretical model was then examined for themagnetic field vector distributions of the spiral-type transmitting coil by using an elliptic coordinate system. The relationshipbetween the position of the receiving coil and the coupling coefficient was determined when the position and attitude changed.Finally, the experimental device of the wireless power supply system of the endoscope was designed with a class-E amplifierand Liz coil. The simulation and experimental results showed that the proposed method can generate high intensity magneticfield uniform, which can improve the efficiency of the wireless power transmission in the case of axial deviation and angularmisalignment. The experimental results also indicated that the proposed scheme can meet the needs of the power supply ofwireless endoscopes.


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How to Cite
CUI, Chang; ZHAO, Qiang; LI, Zhongjian. Design of Wireless Power Supply Optimized Structure for Capsule Endoscopes. Journal of Power Technologies, [S.l.], v. 96, n. 2, p. 101--109, july 2016. ISSN 2083-4195. Available at: <>. Date accessed: 14 july 2024.
Energy Engineering and Technology

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