Apparatus and method for non-compliant object detection

A method for wirelessly transferring power, the method comprising:

• wirelessly transmitting power over a time period at a power level sufficient to power or charge a chargeable device positioned within a charging region;
• determining a first power measurement P1(PTU) of the power level provided by the wireless power transmitter at a first sample time T1 within the time period, a second power measurement P2(PTU) of the power level provided by the wireless power transmitter at a second sample time T2 within the time period after the first sample time T1, and a third power measurement P3(PTU) of the power level provided by the wireless power transmitter at a third sample time T3 within the time period after the second sample time T2 wherein the wireless power transmitter is wirelessly transmitting power to power or charge the chargeable device as the sample times T1, T2 and T3,
• determining a first power difference Δ1(PTU) between the first power measurement P1(PTU) and the second power measurement P2(PTU),
• determining a second power difference Δ2(PTU) between the second power measurement P2(PTU) and the third power measurement P3(PTU),
• determining a transmitter power difference Δτ between the first power difference Δ1(PTU) and the second power difference Δ2(PTU), and
• determining an absence or a presence of an object that affects consumption of power transmitted by the wireless power transmitter based at least on the transmitter power difference Δτ.

An apparatus for wirelessly transferring power, the apparatus comprising:

• means for wirelessly transmitting power over a time period at a power level sufficient to power or charge a chargeable device positioned within a charging region;
• means for determining a first power measurement P1(PTU) of the power level provided by the wireless power transmitter at a first sample time T1 within the time period, a second power measurement P2(PTU) of the power level provided by the wireless power transmitter at a second sample time T2 within the time period after the first sample time T1, and a third power measurement P3(PTU) of the power level provided by the wireless power transmitter at a third sample time T3 within the time period after the second sample time T2 wherein the wireless power transmitter is wirelessly transmitting power to power or charge the chargeable device as the sample times T1, T2 and T3,
• means for determining a first power difference Δ1(PTU) between the first power measurement P1(PTU) and the second power measurement P2(PTU),
• means for determining a second power difference Δ2(PTU) between the second power measurement P2(PTU) and the third power measurement P3(PTU),
• means for determining a transmitter power difference Δτ between the first power difference Δ1(PTU) and the second power difference Δ2(PTU), and
• means for determining an absence or a presence of an object that affects consumption of power transmitted by the transmitting means based at least on the transmitter power difference Δτ.