Systems and methods for protecting switching elements in an induction heating system

An induction heating system comprising:

• an induction heating coil operable to inductively heat a load with a magnetic field;
• a power supply circuit configured to supply a power signal to the induction heating coil at an operating frequency, the power supply circuit including at least one switching element;
• a detector circuit configured to detect a feedback signal associated with a signal flowing through the induction heating coil, the detector circuit providing an output signal having a duty cycle, the duty cycle of the output signal being based at least in part on a percentage of the feedback signal that is greater or less than a reference signal, the duty cycle of the output signal corresponding to the proximity of the operating frequency to resonance of the induction heating system;
• and
• a control circuit configured to control the power supply circuit;
• wherein the control circuit is further configured to:
• calculate a switching power loss associated with the at least one switching element based at least in part on the duty cycle of the output signal;
• and
• adjust the operating frequency of the induction heating system based at least in part on the switching power loss.

A method for protecting a switching element of a power supply circuit in an induction cooktop, the method comprising:

• calculating a switching power loss associated with the switching element;
• classifying the switching power loss into one of a plurality of threat zones based upon the magnitude of the switching power loss;
• and
• adjusting the operating frequency of the power supply circuit based upon the threat zone into which the switching power loss is classified.