Patent ID: 9716388
Date: 2017-07-25
CPC Classifications: G01R,H02J

Claim:
1. A power transmitter for transferring power to a power receiver using a wireless inductive power signal, the power transmitter comprising: an inductor for providing the power signal; a power signal generator for driving the inductor to provide the power signal; a calibration controller for determining whether a power loss calibration has been performed for the power transmitter and power receiver pairing, the power loss calibration determining an expected relationship between a received power indication provided by the power receiver and a transmitted power indication for the power transmitter; a power limiter arranged to restrict a power provided to the inductor to not exceed a threshold unless a power loss calibration has been performed for the power transmitter and power receiver pairing; a receiver for receiving received power indications from the power receiver; and a detector for detecting a parasitic power consumption in response to a deviation between a relationship between the transmitted power indication and the received power indication and the expected relationship between the transmitted power indication and the received power indication exceeding a threshold.