Patent ID: 11917743
Assignee: WHIRLPOOL CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. An electromagnetic cooking device comprising:
a cavity in which a food load is placed;
a plurality of RF feeds configured to introduce electromagnetic radiation into the cavity for heating the food load; and
a controller configured to:
(a) measure resonances in the cavity;
(b) generate and store a resonance map resulting from the measured resonances, the resonance map is represented in a frequency/phase domain and includes a plurality of efficiency measurements each taken at different frequencies and phase differences;
(c) conditionally repeat steps (a) and (b) to obtain and store a plurality of resonance maps over time;
(d) detect a melting state of the food load based on variations between any of the measured efficiencies in the stored resonance maps; and
(e) adjust a power level of the electromagnetic radiation in response to detection of the melting state.