| 摘要 |
<p>A power transmitter (101) transfers power to a power receiver (105) using a wireless power signal. The power transmitter (101) comprises an inductor (103) driven by a power signal generator (201) to provide the power signal. A calibration controller (211) determines whether a power loss calibration has been performed for the power transmitter (101) and power receiver (105) pairing. The calibration adapts an expected relationship between a received power indication provided by the power receiver (105) and a transmitted power indication for the power transmitter (101). A power limiter (205) restricts the power provided to the inductor to not exceed a threshold unless a power loss calibration has been performed for the pairing. The expected relationship may be used to detect unaccounted for power losses, e.g. due to foreign objects being present. The calibrated expected relationship may provide improved accuracy allowing accurate detection at higher power levels. At lower power levels such accuracy is not needed, and no calibration needs to be performed.</p> |
