One of the main challenges in the application of wireless power transmission systems is to achieve stable power transmission and constant transmission power under dynamically changing coupling conditions. A parity-time symmetric model for AUV (autonomous underwater robot) is proposed. Based on the coupling mode theory, the robustness of the parity-time symmetric wireless transmission system is investigated. The theoretical analysis shows that the AUV wireless power transmission system based on parity time symmetry can automatically obtain constant output power and constant transmission efficiency when the coupling coefficient is varied. Based on this theory, the experimental prototype was built by simulating the effects of relevant parameters using LTspice. And the experiments were conducted in air medium and seawater medium respectively. The experimental results show that under the condition of parity time symmetry, the underwater wireless energy transmission voltage ratio is close to 1, and the transmission efficiency reaches 15%, in the range of 12.5 cm. The theoretical derivation has been verified.
2. Wu, L., B. Zhang, and J. Zhou, "Efficiency improvement of the parity-time-symmetric wireless power transfer system for electric vehicle charging," IEEE Transactions on Power Electronics, Vol. 35, No. 15, 12497-12508, 2020.
3. Zhou, J., D. J. Li, and Y. Chen, "Frequency selection of an inductive contactless power transmission system for ocean observing," Ocean Engineering, Vol. 60, No. 5, 175-185, 2013.
4. Hamam, R. E., et al., "Efficient weakly-radiative wireless energy transfer: An EIT-like approach," Annals of Physics, Vol. 324, No. 8, 1783-1795, 2009.
5. Beh, T. C., et al., "Basic study of improving efficiency of wireless power transfer via magnetic resonance coupling based on impedance matching," IEEE International Symposium on Industrial Electronics, 2011-2016, 2013.
6. Ali, B. J., Y. Lee, and Y. Kim, "Design and implementation of autonomous wireless charging station for rotary-wing UAVs," Aerospace Science and Technology, Vol. 54, No. 7, 253-266, 2016.
7. Wang, C. and M. Zheng, "Design of wireless power transfer device for UAV," 2016 IEEE International Conference on Mechatronics & Automation, 2449-2454, 2016.
8. Campi, T., et al., "Magnetic field levels in drones equipped with Wireless Power Transfer technology," Asia-pacific International Symposium on Electromagnetic Compatibility, 544-547, 2016.
9. Mostafa, T. M., A. Muharam, and R. Hattori, "Wireless battery charging system for drones via capacitive power transfer," IEEE PELS Workshop on Emerging Technologies: Wireless Power Transfer (WoW), 1-6, 2017.
10. Kelis, G., et al., "Hybrid class-E synchronous rectifier for wireless powering of quadcopters," IEEE Wireless Power Transfer Conference (WPTC), 1-4, 2017.
11. Aldhaher, S., et al., "Light-weight wireless power transfer for mid- air charging of drones," 2017 11th European Conference on Antennas and Propagation (EUCAP), 336-340, 2017.
12. Assawaworrarit, S., X. Yu, and S. Fan, "Robust wireless power transfer using a nonlinear parity- time-symmetric circuit," Nature, Vol. 546, No. 7658, 387-390, 2017.
13. Schindler, J., et al., "Experimental study of active LRC circuits with PT symmetries," Physical Review, Vol. 84, No. 1, 4-4, 2011.
14. Bertolotti, M., "Waves and fields in optoelectronics," Prentice-Hall, Vol. 32, No. 7, 748-748, 1985.
15. Schindler, J., et al., "PT-symmetric electronics," Journal of Physics A: Mathematical & Theoretical, Vol. 45, No. 44, 2077-2082, 2012.
16. Hassan, A. U., et al., "Nonlinear reversal of PT symmetric phase transition in a system of coupled semiconductor micro-ring resonators," SPIE Nanoscience + Engineering 2016, 2016.
17. Fu, M., et al., "Analysis and tracking of optimal load in wireless power transfer systems," IEEE Transactions on Power Electronics, Vol. 30, No. 7, 3952-3963, 2015.
18. Liu, F., et al., "A multifrequency superposition methodology to achieve high efficiency and targeted power distribution for a multiload MCR WPT system," IEEE Transactions on Power Electronics, Vol. 33, No. 10, 9005-9016, 2017.