Abstract
Wireless charging of smartphones using inductive wireless power transfer (IWPT) has become very popular. However, the efficiency of IWPT systems can decrease substantially when the transmitting and receiving coils are not closely coupled. One popular approach to mitigate the efficiency degradation is to utilize higher frequency. However, the higher efficiency is only achieved at a specific range of load resistance, which may not be feasible in real applications. In this work, we analyze the effect of frequency and load variations on the power transfer efficiency of a typical two-coil IWPT setup, based on a numerical model. The results show that lower frequency systems are favored for low load resistances, and vice versa for high load resistances. For example, when the coils' inductance is 20μH and the load resistance is below 3.4 ohms, then operation at lower frequencies is recommended even when the coupling factor is as low as 0.1.
| Original language | English |
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| Title of host publication | 17th European Conference on Antennas and Propagation, EuCAP 2023 |
| Publisher | IEEE - Institute of Electrical and Electronics Engineers Inc. |
| ISBN (Electronic) | 9788831299077 |
| DOIs | |
| Publication status | Published - 2023 |
| Event | 17th European Conference on Antennas and Propagation, EuCAP 2023 - Florence, Italy Duration: 2023 Mar 26 → 2023 Mar 31 |
Conference
| Conference | 17th European Conference on Antennas and Propagation, EuCAP 2023 |
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| Country/Territory | Italy |
| City | Florence |
| Period | 2023/03/26 → 2023/03/31 |
Subject classification (UKÄ)
- Other Electrical Engineering, Electronic Engineering, Information Engineering
Free keywords
- Inductive wireless power transfer
- optimal load
- power transfer efficiency
- resonant frequency