Patent Document ID: 9536656
Application ID: 13891168
Patent Flag: 1

Claim One:
1. A method comprising: transferring power from a transmitter to a receiver in a wireless power system; measuring input power to the transmitter; receiving a message from the receiver indicating power received at the receiver; determining an amount of power lost in the transferring to indicate a presence of a parasitic loss in the wireless power system; determining a portion of the transferred power attributed to parasitic loss in a foreign object; reducing the power transmitted from the transmitter to a non-zero level so that the portion of transferred power lost in the foreign object does not exceed a predetermined safe level; and ignoring messages from the receiver requesting a higher level of transmitted power, wherein the presence of a parasitic loss is determined by comparing measured losses to expected losses, the expected losses determined by measuring system characteristics in a controlled environment, by applying a mathematical fit of the system characteristics to an equation for predicting parasitic losses, wherein the equation calculates expected loss as the sum of: a first constant multiplied by the square of transmitter peak voltage; a second constant multiplied by the transmitter peak voltage; and a third constant.