US 11,968,765 B2
Induction cooking system
Jeremiah Kopiness, Saukville, WI (US); Andrew Amrhein, Sheboygan, WI (US); Jong-Woo Kim, Blacksburg, VA (US); Moonhyun Lee, Blacksburg, VA (US); and Jih-Sheng Lai, Blacksburg, VA (US)
Assigned to The Vollrath Company, L.L.C., Sheboygan, WI (US); and Virginia Tech Intellectual Properties, Inc., Blacksburg, VA (US)
Filed by The Vollrath Company, L.L.C., Sheboygan, WI (US); and Virginia Tech Intellectual Properties, Inc., Blacksburg, VA (US)
Filed on Oct. 18, 2019, as Appl. No. 16/657,472.
Claims priority of provisional application 62/812,894, filed on Mar. 1, 2019.
Prior Publication US 2020/0281048 A1, Sep. 3, 2020
Int. Cl. H05B 6/06 (2006.01); H02M 1/00 (2006.01); H02M 7/48 (2007.01); H02M 7/5387 (2007.01); H03L 5/00 (2006.01); H05B 6/12 (2006.01)
CPC H05B 6/062 (2013.01) [H02M 1/0009 (2021.05); H02M 7/53871 (2013.01); H03L 5/00 (2013.01); H05B 6/1209 (2013.01); H02M 7/4815 (2021.05); Y02B 70/10 (2013.01)] 11 Claims
OG exemplary drawing
 
9. A circuit for inductively heating cookware, the circuit comprising:
a series resonant inverter circuit comprising a plurality of switches and one or more induction coils structured to inductively couple to the cookware to heat the cookware, the inverter circuit comprising a voltage sensor configured to sense a voltage across at least one of the plurality of switches; and
a control circuit configured to control switching of a first set of one or more of the plurality of switches based on the voltage sensed across the at least one of the plurality of switches, wherein the control circuit comprises:
a comparator module configured to compare a first sensed voltage signal and a second sensed voltage signal to a calculated bias voltage and provide a comparator output, the calculated bias voltage calculated based on a target current, wherein the target current is the current at which the control circuit turns off or turns on one or more of the plurality of switches to implement zero current switching and/or zero voltage switching; and
a pulse width modulation module configured to implement the zero current switching a nd/or zero voltage switching using the comparator output by providing a control signal to the plurality of switches based on the comparator output.