Abstract
Aiming at the detection needs of metal foreign matters in high-power wireless charging system, a method of metal foreign matter detection based on the impedance change of monitor coil has been proposed. By the monitor coil array laying on the surface of transmitter coil and monitoring its impedance change, the presence and location of metal matters could be detected. Also, a method to eliminate the harm of metal matters based on the passive shielding of monitor coil is proposed. Benefitting from the induced current inside monitor coil, the magnetic field and the heat of metal matters are reduced effectively which guarantee the normal charging process in presence of metal matters. Firstly, the mutual inductance coupling model of metal matter and monitor coil is built, and the detection principle based on the change between monitor coil impedance is demonstrated. Then the relationship between power loss and magnetic induction intensity is analyzed, and a passive shielding circuit is designed. Finally, experimental verification was carried out on a 3.3 kW wireless charging prototype, and the detection system could accurately detect the existence and location of 1-yuan coin. Under the continuous operation of wireless charging system and the shielding effect of monitor coil, its equilibrium temperature drops from 83.4 ℃ to 62.2 ℃, which is lower than the safety threshold of 80 ℃ in the current standard, ensuring the continuity of wireless charging process and system security.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Sun, L., Ma, D., Tang, H.: A review of recent trends in wireless power transfer technology and its applications in electric vehicle wireless charging. Renew. Sustain. Energy Rev. 91, 490–503 (2018)
Xue, M., Yang, Q., Zhang, P., et al.: Application status and key issues of wireless power transmission technology. Trans. China Electrotech. Soc. 36(08), 1547–1568 (2021). https://doi.org/10.19595/j.cnki.1000-6753.tces.200059. (in Chinese)
Wu, L., Zhang, B.: Overview static wireless charging technology for electric vehicles: part. Trans. China Electrotech. Soc. 35(08), 1662–1678 (2020). https://doi.org/10.19595/j.cnki.1000-6753.tces.190107. (in Chinese)
SAEJ2954_201904, Wireless power transfer for light-duty plug-in/electric vehicles and alignment methodology wireless power transfer for light-duty plug-in/electric vehicles and alignment methodology (2019)
IEC 61980–1: 2015/COR1: 2017 corrigendum 1-electric vehicle wireless power transfer (WPT) systems-part 1: general requirements (2017)
Jeong, S.Y., Kwak, H.G., Jang, G.C., et al.: Dual-purpose non-overlap** coil sets as metal object and vehicle position detections for wireless stationary EV chargers. IEEE Trans. Power Electron. 33(9), 7387–7397 (2018)
Jang, G,C., Jeong, S.Y., Kwak, H.G., et al.: Metal object detection circuit with non-overlapped coils for wireless EV chargers In: 2016 IEEE 2nd Annual Southern Power Electronics Conference (SPEC), Auckland, pp. 1–6 (2016)
Jeong, S.Y., Thai, V.X., Park, J.H., et al.: Self-inductance based metal object detection with mistuned resonant circuits and nullifying induced voltage for wireless EV chargers. IEEE Trans. Power Electron. 34(1), 748–758 (2019)
Jeong, S.Y., Thai, V.X., Park, J.H., et al.: Metal object detection system with parallel-mistuned resonant circuits and nullifying induced voltage for wireless EV chargers. In: 2018 International Power Electronics Conference (IPEC). Niigata, pp. 2564–2568 (2018)
Meichle, D.P.: Foreign object detection in wireless energy transfer systems. WO2017/0700227A1[P] 27 April (2017)
Widmer, H., Sieber, L., Daetwyler, A., et al.: Systems, methods, and apparatus for radar-based detection of objects in a predetermined space: US, 977240125[P] 2017–9–26
Zhang, X., **ng, Z., Xue, M., et al.: Overview of foreign object detection in wireless power transfer system[J/OL]. Trans. China Electrotech. Soc. 1–15 [2021–12–16]
Chen, C., Huang, X., Sun, W., et al.: Impact of metal obstacles on wireless power transmission system based coupled resonance. Trans. China Electrotech. Soc. 29(9), 22–26 (2014). (in Chinese)
Su, Y., Hou, X., Dai, X.: Review of foreign object detection technology in magnetic coupling wireless power transfer system. Proc. Chin. Soc. Electrical Eng. 41(2), 715–728 (2021)
Acknowledgment
This academic research was supported and funded by General Program of National Natural Science Foundation of China No. 51977043.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2023 Bei**g Paike Culture Commu. Co., Ltd.
About this paper
Cite this paper
Sun, Y., Song, K., Zhou, T., Wei, G., Zhu, C. (2023). Metal Foreign Matter Detection and Hazard Elimination Based on Passive Shield of Monitor Coils. In: **e, K., Hu, J., Yang, Q., Li, J. (eds) The Proceedings of the 17th Annual Conference of China Electrotechnical Society. ACCES 2022. Lecture Notes in Electrical Engineering, vol 1014. Springer, Singapore. https://doi.org/10.1007/978-981-99-0408-2_96
Download citation
DOI: https://doi.org/10.1007/978-981-99-0408-2_96
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-99-0407-5
Online ISBN: 978-981-99-0408-2
eBook Packages: EngineeringEngineering (R0)