US 11,888,337 B2
Input parasitic metal detection
David W. Baarman, Fennville, MI (US); Joshua K. Schwannecke, Grand Rapids, MI (US); Neil W. Kuyvenhoven, Ada, MI (US); Esai E. Umenei, Grand Rapids, MI (US); Dale R. Liff, Kent, OH (US); Andrew C. Zeik, Hudson, OH (US); Mark A. Blaha, Twinsburg, OH (US); Jason L. Amistadi, Lyndhurst, OH (US); and Robert D Gruich, Copley, OH (US)
Assigned to Philips I.P. Ventures B.V., Eindhoven (NL)
Filed by PHILIPS IP VENTURES B.V., Eindhoven (NL)
Filed on Dec. 2, 2020, as Appl. No. 17/109,269.
Application 17/109,269 is a continuation of application No. 15/350,191, filed on Nov. 14, 2016, granted, now 10,862,335.
Application 15/350,191 is a continuation of application No. 14/090,582, filed on Nov. 26, 2013, granted, now 9,524,822.
Application 14/090,582 is a continuation of application No. 13/022,944, filed on Feb. 8, 2011, granted, now 8,620,484.
Claims priority of provisional application 61/302,349, filed on Feb. 8, 2010.
Prior Publication US 2021/0083522 A1, Mar. 18, 2021
Int. Cl. G01R 21/00 (2006.01); G01V 3/02 (2006.01); H01F 38/14 (2006.01); H02J 50/12 (2016.01); H02J 50/60 (2016.01); H02J 7/00 (2006.01); H02J 50/70 (2016.01); H02J 50/90 (2016.01)
CPC H02J 7/0047 (2013.01) [G01R 21/00 (2013.01); G01V 3/02 (2013.01); H01F 38/14 (2013.01); H02J 50/12 (2016.02); H02J 50/60 (2016.02); H02J 50/70 (2016.02); H02J 50/90 (2016.02)] 45 Claims
OG exemplary drawing
 
1. A method of controlling an inductive power transfer circuit the method comprising:
measuring an input characteristic of input power in a primary circuit,
wherein the primary circuit comprises a tank circuit and a switching circuit,
wherein the primary circuit generates an electromagnetic field;
measuring a tank characteristic of power in the tank circuit;
receiving, in the primary circuit, secondary device information from a at least one secondary device, wherein the secondary device is arranged to couple to the primary circuit via the electromagnetic field;
estimating power consumption in the inductive power transfer system as a function of at least the tank characteristic;
comparing the input characteristic, the secondary device information, and the estimated power consumption to determine when there is an unacceptable amount of parasitic metal present in proximity to the primary circuit; and
restricting or stopping the inductive power transfer from the primary circuit in response to a determination that the unacceptable amount of parasitic metal is present in proximity to the primary circuit.