![Lecture image placeholder](/_next/image?url=https%3A%2F%2Fassets.underline.io%2Flecture%2F63076%2Fposter_document_thumbnail_extract%2Flarge-685f4f6fa854261979575ce826fbe969.jpg&w=3840&q=75)
Premium content
Access to this content requires a subscription. You must be a premium user to view this content.
![Lecture placeholder background](/_next/image?url=https%3A%2F%2Fassets.underline.io%2Flecture%2F63076%2Fposter_document_thumbnail_extract%2Flarge-685f4f6fa854261979575ce826fbe969.jpg&w=3840&q=75)
poster
Analysis and Design of Constant Current and Constant Voltage Outputs of Integrated Coil Wireless EV Charging System
I Introduction:
Typically, EVs adopt lithium-ion batteries as power supply. Therefore, constant current (CC) mode and constant voltage (CV) mode can be implemented for battery charging applications.
At present, various control strategies have been proposed. However, these methods require complex control strategies and additional components, often lead to increased switching
losses1 and frequency bifurcation2, and are difficult to achieve with zero phase angle input (ZPA). In this paper, a switchable hybrid compensation structure is designed to achieve loadindependent
output current and load-independent output voltage under ZPA conditions by switching the receiver-side compensation structure without additional devices and complex
control methods.
II Method and Discussion
A hybrid topology using different compensations in the receiver side, i.e., LC-LC compensation and LC-LCCL compensation is developed. Meanwhile, the compensation coil is integrated
into the receiving coil, the magnetic field is enhanced without any reactive power flow between the compensation and receiving coils, which can effectively improve the power
transmission distance, efficiency, and capacity. At a fixed frequency, no complicated control methods are required, and constant voltage and constant current can be achieved under ZPA
conditions. Besides, by optimizing the integrated coil and designing compensation parameters, the system can still maintain good CC-CV output characteristics when misalignment
happens.
III Conclusion
According to the experimental results, the wireless charging system can operate within 100mm misalignment in X-axis when the maximum fluctuations of the charging current IB in CC
mode and the charging voltage VB in CV mode are less than 7% which is consistent well with the theoretical analysis. Besides, the wireless charging system can achieve the maximum
efficiency at 93.43% with a 15-cm air gap when delivering 1442 W to the load.
References:
1 Z. Li, C. Zhu, J. Jiang, K. Song, and G. Wei, “A 3 kW wireless power transfer system for sightseeing car supercapacitor charge,” IEEE Trans. Power Electron., vol. 32, no.
5, pp. 3301–3316, May. 2017.
2 C. W. Wang, G. A. Covic, and O. H. Stielau, “Power transfer capability and bifurcation phenomena of loosely coupled inductive power transfer systems,” IEEE Trans. Ind. Electron.,
vol. 51, no. 1, pp. 148–157, Feb. 2004