The electrical representation of the contactless power transfer (CPT) system with a coaxial transformer for the power traction in the rotary drilling system is presented. The air gap in the rotary transformer can lead to a lot of leakage inductance, so that the series-series (SS) compensation capacitors are used to increase the efficiency and the capability of the system. Moreover, the frequency response of the SS compensated CPT system is analyzed, and the transfer characteristics of the CPT system are revealed at different resonant frequencies. It is shown that the phase angle of the input impedance at resonant frequency determines the operation mode of the CPT system. At resonant frequency ω0, the system can operate in constant-current (CC) mode, whereas at resonant frequency ωH, it can work in constant-voltage (CV) mode. In the application of the drilling system, the CV mode owning good load regulation is more preferred than the CC mode for a wide range of load variation. At last, the analysis result is verified by experiment. The experimental results indicate that the CPT system in the CV mode can produce a 30~35 V voltage output and can transfer maximum power 180 W with an efficiency of 78.5%. The proposed CPT system can well meet the requirement of power supply in the drilling system.
2. Chen, Q., S. C. Wong, and C. K. Tse, "Analysis, design, and control of a transcutaneous power regulator for artificial hearts," IEEE Trans. Biomed. Circuits Syst., Vol. 3, No. 1, 23-31, 2009.
3. Mohammad, H. and S. Reem, "Wireless power transfer approaches for medical implants: A review," Signals, Vol. 1, 209-229, 2020.
4. Agarwal, K., R. Jegadeesan, and Y. X. Guo, "Wireless power transfer strategies for implantable bioelectronics," IEEE Rev. Biomed. Eng., Vol. 10, 136-161, 2017.
5. Jung, S., H. Lee, and C. S. Song, "Optimal operation plan of the online electric vehicle system through establishment of a DC distribution system," IEEE Trans. Power Electron., Vol. 28, No. 12, 5878-5889, 2013.
6. Ali, Z., V. Z. Sadegh, and B. Amir, "A dynamic WPT system with high efficiency and high power factor for electric vehicles," IEEE Trans. Power Electron., Vol. 35, No. 7, 6732-6740, 202.
7. Kadem, K., F. Benyoubi, M. Bensetti, Y. L. Bihan, E. Labouré, and M. Debbou, "An efficient method for dimensioning magnetic shielding for an induction electric vehicle charging system," Progress In Electromagnetics Research, Vol. 170, 153-167, 2021.
8. Yan, Z. C., B. W. Song, and Y. M. Zhang, "A rotation-free wireless power transfer system with stable output power and efficiency for autonomous underwater vehicles," IEEE Trans. Power Electron., Vol. 34, No. 5, 4005-4008, 2019.
9. Song, K., B. Q. Ma, and G. Yang, "A rotation-light weight wireless power transfer system for solar wing driving," IEEE Trans. Power Electron., Vol. 34, No. 9, 8816-8830, 2019.
10. Papastergiou, K. D. and D. E. Macpherson, "An airborne radar power supply with contactless transfer of energy-part I: Rotating transformer," IEEE Trans. Ind. Electron., Vol. 54, No. 5, 2874-2884, 2007.
11. Moradewicz, A., "Contactless energy transmission system with rotatable transformer-modeling, analyzes and design,", Ph.D. Dissertation, Electrotechnical Institute, Warsaw, Poland, 2008.
12. Zhang, W. and C. C. Mi, "Compensation topologies of high-Power wireless power transfer systems," IEEE Trans. Veh. Technol., Vol. 65, No. 6, 4768-4778, 2016.
13. Zhang, W., S. Wong, and C. K. Tse, "Design for efficiency optimization and voltage controllability of series-series compensated inductive power transfer systems," IEEE Trans. Power Electron., Vol. 29, No. 1, 191-200, 2014.
14. Trevisan, R. and A. Costanzo, "State-of-the-art of contactless energy transfer (CET) systems: Design rules and applications," Wireless Power Transfer, Vol. 1, No. 1, 10-20, 2014.
15. Steigerwald, R. L., "A comparison of half-bridge resonant converter topologies," IEEE Trans. Power Electron., Vol. 3, No. 2, 174-182, 1988.
16. Cheng, B. and L. Z. He, "High-order network based general modeling method for improved transfer performance of the WPT system," IEEE Trans. Power Electron., Vol. 36, No. 11, 12375, 2021.