Granted Patent B2

US 12,382,552 · App. 17/607,187 · Granted Aug 5, 2025

Inventors: Andrew L. Bleloch (Kenmore, WA); Peter Nysen (Campbell, CA); Neeraj S. Bhardwaj (Nevada City, CA); Matthew Greenfield (Santa Cruz, CA)

Assignee: Philip Morris Products, S.A.

H05B6/06A24F40/465A24F40/57

Abstract

Claims (87)

1. A system for determining a temperature of a susceptor element comprising:

an induction heating circuit comprising an inductor element and

a capacitor element;

at least one processor programmed or configured to:

determine a first response phase of the induction heating circuit, wherein the first response phase is based on a magnetic property of the susceptor element at a first driving frequency, and wherein the first response phase is a value of phase difference between a phase of a driving current at the first driving frequency and a phase of a voltage across an electrical component of the induction heating circuit at the first driving frequency;

determine a second response phase of the induction heating circuit, wherein the second response phase is based on a magnetic property of the susceptor element at a second driving frequency, and wherein the second response phase is a value of phase difference between a phase of a driving current at the second driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the second driving frequency;

determine a function of phase versus frequency for the induction heating circuit based on the first response phase and the second response phase;

determine a frequency value where a phase value of the function is in quadrature based on the function of phase versus frequency;

determine a temperature of the susceptor element based on the frequency value; and

adjust an amount of electrical energy provided to the inductor element based on the temperature of susceptor element.

2. The system of claim 1 , wherein the at least one processor is further programmed or configured to:

determine a third response phase of the induction heating circuit, wherein the third response phase is based on a magnetic property of the susceptor element at a third driving frequency, and wherein the third response phase is a value of phase difference between a phase of a driving current at the third driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the third driving frequency; and

determine a fourth response phase of the induction heating circuit, wherein the fourth response phase based on a magnetic property of the susceptor element at a fourth driving frequency, and wherein the fourth response phase is a value of phase difference between a phase of a driving current at the fourth driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the fourth driving frequency; and

wherein, when determining the function of phase versus frequency for the induction heating circuit, the at least one processor is programmed or configured to:

determine the function of phase versus frequency for the induction heating circuit based on the first response phase, the second response phase, the third response phase, and the fourth response phase.

3. The system of claim 2 , wherein the function comprises a polynomial, and

wherein, when determining the function of phase versus frequency, the at least one processor is programmed or configured to:

determine polynomial coefficients of the polynomial that is fit to the first response phase of the induction heating circuit, the second response phase of the induction heating circuit, the third response phase of the induction heating circuit, and the fourth response phase of the induction heating circuit, and

wherein, when determining the frequency value where the response phase value of the function is in quadrature, the at least one processor is programmed or configured to:

determine the frequency value where the phase value of the function is in quadrature based on the polynomial coefficients of the polynomial.

4. The system of claim 1 , wherein, when determining the function of phase versus frequency based on the first response phase and the second response phase, the at least one processor is programmed or configured to:

determine polynomial coefficients of a polynomial that is fit to the first response phase of the induction heating circuit and the second response phase of the induction heating circuit, and

wherein, when determining the frequency value where the response phase value of the function is in quadrature, the at least one processor is programmed or configured to:

determine the frequency value where the phase value of the function is in quadrature based on the polynomial coefficients of the polynomial.

5. The system of claim 1 , where the at least one processor is further programmed or configured to:

determine the phase of the voltage across the electrical component of the induction heating circuit at the first driving frequency based on a first measurement of voltage across the capacitor element; and

determine the phase of the voltage across the electrical component of the induction heating circuit at the second driving frequency based on a second measurement of voltage across the capacitor element.

6. The system of claim 1 , further comprising:

at least one temperature sensor; and

wherein, when determining the temperature of the susceptor element, the at least one processor is programmed or configured to:

determine the temperature of the susceptor element based on the frequency value where the phase value of the function is in quadrature and an output of the at least one temperature sensor.

7. A method for determining a temperature of a susceptor element comprising:

determining, with at least one processor, a first response phase of an induction beating circuit comprising an inductor element and a capacitor element, wherein the first response phase is based on a magnetic property of the susceptor element at a first driving frequency, and wherein the first response phase is a value of phase difference between a phase of a driving current at the first driving frequency and a phase of a voltage across an electrical component of the induction heating circuit at the first driving frequency;

determining, with at least one processor, a second response phase of the induction heating circuit, wherein the second response phase is based on a magnetic property of the susceptor element at a second driving frequency, and wherein the second response phase is a value of phase difference between a phase of a driving current at the second driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the second driving frequency;

determining, with at least one processor, a function of phase versus frequency for the induction heating circuit based on the first response phase and the second response phase;

determining, with at least one processor, a frequency value where a phase value of the function is in quadrature based on the function of phase versus frequency; and

determining, with at least one processor, a temperature of the susceptor element based on the frequency value; and

adjusting an amount of electrical energy provided to the inductor element based on the temperature of susceptor element.

8. The method of claim 7 , further comprising:

determining a third response phase of the induction heating circuit, wherein the third response phase is based on a magnetic property of the susceptor element at a third driving frequency, and wherein the third response phase is a value of phase difference between a phase of a driving current at the third driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the third driving frequency; and

determining a fourth response phase of the induction heating circuit, wherein the fourth response phase based on a magnetic property of the susceptor element at a fourth driving frequency, and wherein the third response phase is a value of phase difference between a phase of a driving current at the fourth driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the fourth driving frequency,

wherein determining the function of phase versus frequency for the induction heating circuit comprises:

determining the function of phase versus frequency for the induction heating circuit based on the first response phase, the second response phase, the third response phase, and the fourth response phase.

9. The method of claim 8 , wherein the function comprises a polynomial,

wherein determining the function of phase versus frequency comprises:

determining polynomial coefficients of the polynomial that is fit to the first response phase of the induction heating circuit, the second response phase of the induction heating circuit, the third response phase of the induction heating circuit, and the fourth response phase of the induction heating circuit, and

wherein determining the frequency value where the response phase value of the function is in quadrature comprises:

determining the frequency value where the phase value of the function is in quadrature based on the polynomial coefficients of the polynomial.

10. The method of claim 7 , wherein determining the function of phase versus frequency based on the first response phase and the second response phase comprises:

determining polynomial coefficients of a polynomial that is fit to the first response phase of the induction heating circuit and the second response phase of the induction heating circuit, and

wherein determining the frequency value where the response phase value of the function is in quadrature comprises:

determining the frequency value where the phase value of the function is in quadrature based on the polynomial coefficients of the polynomial.

11. The method of claim 7 , further comprising:

determining the phase of the voltage across the electrical component of the induction heating circuit at the first driving frequency based on a first measurement of voltage across the capacitor element; and

determining the phase of the voltage across the electrical component of the induction heating circuit at the second driving frequency based on a second measurement of voltage across the capacitor element.

12. The method of claim 7 , wherein determining the temperature of the susceptor element comprises:

determining the temperature of the susceptor element based on a measurement of a magnetic field generated by the inductor element of the induction heating circuit and the frequency value where the phase value of the function is in quadrature.

13. The method of claim 7 , further comprising:

determining a measurement of a magnetic field generated by the inductor element,

wherein determining the temperature of the susceptor element comprises:

determining the temperature of the susceptor element based on the measurement of the magnetic field generated by the inductor element and the frequency value where the phase value of the function is in quadrature.

14. A computer program product for determining a temperature of a susceptor element, the computer program product comprising at least one non-transitory computer-readable medium including one or more instructions that, when executed by at least one processor, cause the at least one processor to:

determine a first response phase of an induction heating circuit comprising an inductor element and a capacitor element, wherein the first response phase is based on a magnetic property of the susceptor element at a first driving frequency, and wherein the first response phase is a value of phase difference between a phase of a driving current at the first driving frequency and a phase of a voltage across an electrical component of the induction heating circuit at the first driving frequency;

determine a second response phase of the induction heating circuit, wherein the second response phase is based on a magnetic property of the susceptor element at a second driving frequency, and wherein the second response phase is a value of phase difference between a phase of a driving current at the second driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the second driving frequency;

determine a function of phase versus frequency for the induction heating circuit based on the first response phase and the second response phase;

determine a frequency value where a phase value of the function is in quadrature based on the function of phase versus frequency;

determine a temperature of the susceptor element based on the frequency value; and

adjust an amount of electrical energy provided to the inductor element based on the temperature of susceptor element.

15. The computer program product of claim 14 , wherein the one or more instructions further cause the at least one processor to:

determine a third response phase of the induction heating circuit, wherein the third response phase is based on a magnetic property of the susceptor element at a third driving frequency, and wherein the third response phase is a value of phase difference between a phase of a driving current at the third driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the third driving frequency; and

determine a fourth response phase of the induction heating circuit, wherein the fourth response phase based on a magnetic property of the susceptor element at a fourth driving frequency, and wherein the third response phase is a value of phase difference between a phase of a driving current at the fourth driving frequency and a phase of a voltage across the electrical component of the induction heating circuit at the fourth driving frequency,

wherein the one or more instructions that cause the at least one processor to determine the function of phase versus frequency for the induction heating circuit cause the at least one processor to:

determine the function of phase versus frequency for the induction heating circuit based on the first response phase, the second response phase, the third response phase, and the fourth response phase.

16. The computer program product of claim 15 , wherein the function comprises a polynomial,

wherein the one or more instructions that cause the at least one processor to determine the function of phase versus frequency cause the at least one processor to:

determine polynomial coefficients of the polynomial that is fit to the first response phase of the induction heating circuit, the second response phase of the induction heating circuit, the third response phase of the induction heating circuit, and the fourth response phase of the induction heating circuit, and

wherein the one or more instructions that cause the at least one processor to determine the frequency value where the response phase value of the function is in quadrature cause the at least one processor to:

determine the frequency value where the phase value of the function is in quadrature based on the polynomial coefficients of the polynomial.

17. The computer program product of claim 14 , wherein the one or more instructions that cause the at least one processor to determine the function of phase versus frequency based on the first response phase and the second response phase cause the at least one processor to:

determine polynomial coefficients of a polynomial that is fit to the first response phase of the induction heating circuit and the second response phase of the induction heating circuit, and

wherein the one or more instructions that cause the at least one processor to determine the frequency value where the response phase value of the function is in quadrature cause the at least one processor to:

determine the frequency value where the phase value of the function is in quadrature based on the polynomial coefficients of the polynomial.

18. The computer program product of claim 14 , wherein the one or more instructions further cause the at least one processor to:

determine the phase of the voltage across the electrical component of the induction heating circuit at the first driving frequency based on a first measurement of voltage across the capacitor element; and

determine the phase of the voltage across the electrical component of the induction heating circuit at the second driving frequency based on a second measurement of voltage across the capacitor element.

19. The computer program product of claim 14 , wherein the one or more instructions that cause the at least one processor to determine the temperature of the susceptor element cause the at least one processor to:

determine the temperature of the susceptor element based on a measurement of a magnetic field generated by the inductor element of the induction heating circuit and the frequency value where the phase value of the function is in quadrature.

Assignments (1)

Continuity (4)

References Cited (20)