INDUCTION COOKTOP PAN SENSING

1 . An induction heating system comprising:

an induction heating coil operable to inductively heat a load with a magnetic field;

a detector for detecting a current through the coil and providing a feedback current signal representative of the current; and

a controller with a memory in communication with a processor, the memory including program instructions for execution by the processor to:

detect a presence of the load on the induction heating coil based on a characteristic of the feedback current signal;

determine a resonant frequency of the system with the load from a characteristic of the feedback current signal;

determine an operational performance characteristic of the system; and

output an indication of the operational performance characteristic of the system.

2 . The system of claim 1 , wherein the memory further includes program instructions for execution by the processor to:

detect a first position of the load on the induction heating coil;

determine an amount of power coupling to the load at the first position; and

output an indication of the amount of power coupling to the load at the first position.

3 . The system of claim 2 , wherein the memory further includes program instructions for execution by the processor to:

detect a second position of the load on the induction heating coil;

determine an amount of power coupling to the load at the second position;

compare the amount of power coupling the load at the first position to the amount of power coupling to the load at the second position; and

output an indication of the comparison.

4 . The system of claim 2 , wherein the memory further includes program instructions for execution by the processor to:

detect the load in multiple positions on the induction heating element; and

compare the amount of power coupled to the load in each position;

determine an optimal position of the load on the induction heating coil, the optimal position corresponding to a position where a maximum amount of power is coupled to the load; and

output an indication of the optimal position.

5 . The system of claim 1 , wherein the memory further includes program instructions for execution by the processor to:

operate the system at an operational frequency;

determine an amount of power coupling to the load at the operational frequency;

calculate the efficiency of the system at the operating frequency, the efficiency being indicative of a quality of the load; and

outputting an indication of the quality.

6 . The system of claim 5 , wherein the operational frequency is the resonant frequency.

7 . The system of claim 1 , the system comprising a multiple induction heating coil induction heating system, and wherein the memory further includes program instructions for execution by the processor to:

determine an amount of power coupled to each of the induction heating coils; and

output an indication of the amount of power coupled to each of the induction heating coils.

8 . The system of claim 1 , further comprising a user interface operatively connected to the controller and configured to receive the indication from the controller and provide a sensory output of the indication.

9 . The system of claim 1 , wherein the sensory output is a visual or audio indicator.

10 . The system of claim 1 , wherein the detector comprises a shunt resistor in series with the high frequency source.

11 . A method for monitoring the operation of an induction heating system including an induction heating coil for heating loads placed thereon, the method comprising:

monitoring a sensor signal of signal representative of a characteristic of the current through the induction heating coil;

detecting a presence of a load on the induction heating coil from the sensor signal;

detecting an amount of power coupled into the load from the sensor signal;

providing an indication of the amount of power that is coupled to the load.

12 . The method of claim 11 , further comprising:

detecting one or more positions of the load on the induction heating coil;

detecting the amount of power coupled to the load at each detected position;

determining an optimal placement of the load on the induction heating coil, the optimal placement of the load corresponding to a position where a maximum amount of power is coupled to the load; and

providing an indication of the optimal placement of the load on the induction heating coil.

13 . The method of claim 11 , further comprising:

operating the induction heating coil at an operational frequency;

determining a quality of the load from a difference between the amount of power coupled to the load at the operational frequency and a maximum output power of the system; and

outputting an indication of the quality of the load.

14 . The method of claim 13 , further comprising:

determining a resonant frequency of the system and load from the sensor signal;

operating the system at the resonant frequency to determine a quality of the load.

15 . The method of claim 10 , further comprising:

detecting an amount of power coupled to each load in a multiple induction heating coil induction heating system; and

outputting an indication of the amount of power coupled to each load.