Nonlinear resonance circuit for wireless power transmission and wireless power harvesting

• US 10,199,869 B2
• Filed: 05/12/2016
• Issued: 02/05/2019
• Est. Priority Date: 05/12/2015
• Status: Active Grant

• Current Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Original Assignee: Board of Regents of the University of Michigan (University of Michigan)
• Inventors: Mortazawi, Amir, Wang, Xiaoyu
• Primary Examiner(s): Borroto, Alfonso Perez
• Assistant Examiner(s): Yeshaw, Esayas
• Application Number:
  US15/153,219
• Publication Number:
  US 20160336810A1
• Time in Patent Office: 999 Days
• CPC Class Codes: H02J 50/05 using capacitive coupling
• CPC Class Codes: H02J 50/12 of the resonant type

Abstract

A nonlinear resonator is presented that enhances the bandwidth while providing high resonance amplitude. The nonlinear resonance circuit is comprised of an inductor electrically coupled to a capacitor, where either the inductor or capacitor is nonlinear. Response of the nonlinear resonance circuit to an excitation signal is described by a family of second-order differential equations with cubic-order nonlinearity, known as Duffing equations.

Claims

1. A nonlinear resonance circuit, comprising:

an inductor; and

a capacitor electrically coupled to the inductor, where one of the inductor or the capacitor is nonlinear and its reactance is a function of voltage or current that is approximated by a polynomial expansion, where the polynomial expansion includes a constant and even order terms, such that the even order terms of the polynomial expansion are dominant and response of the nonlinear resonance circuit to an excitation signal is described by a Duffing equation.

2. The nonlinear resonance circuit of claim 1 wherein the capacitor is nonlinear and whose capacitance is an even function of the voltage or a polynomial expansion of a function having exponents with even values.

3. The nonlinear resonance circuit of claim 1 wherein the capacitor is implemented by two varactor diodes coupled in anti-series with each other.

4. The nonlinear resonance circuit of claim 1 wherein the capacitor is nonlinear and is implemented by one or more ferroelectric varactors.

5. The nonlinear resonance circuit of claim 1 wherein the capacitor is nonlinear and is implemented by one or more ceramic capacitors.

6. The nonlinear resonance circuit of claim 1 wherein the inductor is nonlinear and whose inductance is an even function of conduction current or a polynomial expansion of a function having exponents with even values.

7. A wireless power harvester, comprising:

an antenna; and

a nonlinear resonance circuit electrically coupled to the antenna and implemented according to claim 1.

8. A wireless power transmission system, comprising:

a transmit coil;

a receive coil; and

a nonlinear resonance circuit electrically coupled to one of the transmit coil or the receive coil, where the nonlinear resonance circuit is implemented according to claim 1.

9. The wireless power transmission system of claim 8 where the coupling mechanism between the transmission coil and the receive coil is one or inductive coupling or capacitive coupling.

10. The nonlinear resonance circuit of claim 1 wherein the inductor is nonlinear and the capacitor is nonlinear.

11. The nonlinear resonance circuit of claim 1 wherein the capacitor is nonlinear and is implemented by any one of a varactor diode, a ferroelectric varactor, a ceramic capacitor, an active device or combinations thereof.

12. The nonlinear resonance circuit of claim 1 further comprises an antenna, where one of the antenna, the inductor or the capacitor is nonlinear.

13. A wireless power transmission system, comprising:

at least one coil;

a nonlinear resonance circuit electrically coupled to the at least one coil, where the nonlinear resonance circuit is implemented according to claim 1.

14. The nonlinear resonance circuit of claim 1 can receive a signal wirelessly.

15. A nonlinear resonance circuit, comprising:

an inductor; and

a nonlinear capacitor electrically coupled in series or shunt with the inductor, where capacitance of the nonlinear capacitor is an even function of the voltage or a polynomial expansion of a function having exponents with even values, and response of the nonlinear resonance circuit to an excitation signal is described by a second-order differential equation with cubic or higher order nonlinearity terms.

16. The nonlinear resonance circuit of claim 15 wherein the nonlinear capacitor is implemented by two varactor diodes coupled in anti-series with each other.

17. The nonlinear resonance circuit of claim 15 wherein the nonlinear capacitor is implemented by one or more ferroelectric varactors.

18. The nonlinear resonance circuit of claim 15 wherein the nonlinear capacitor is implemented by one or more ceramic capacitors which are driven to exhibit nonlinearity.

19. The nonlinear resonance circuit of claim 15 response of the nonlinear resonance circuit to an excitation signal is described by

20. A wireless power harvester, comprising:

a antenna; and

a nonlinear resonance circuit electrically coupled to the antenna and implemented according to claim 15.

21. A wireless power transmission system, comprising:

at least one coil;

a nonlinear resonance circuit electrically coupled to or includes the at least one coil, where the nonlinear resonance circuit is implemented according to claim 15.

22. A nonlinear resonance circuit, comprising:

a nonlinear inductor; and

a capacitor electrically coupled to the inductor, where inductance of the nonlinear inductor is an even function of conduction current or a polynomial expansion of a function having exponents with even values, and response of the nonlinear resonance circuit to an excitation signal is described by a second-order differential equation with cubic or higher order nonlinearity terms.

23. The nonlinear resonance circuit of claim 22 wherein the inductor is nonlinear and is implemented with ferrite core materials.

24. A wireless power transmission system, comprising:

at least one coil;

a nonlinear resonance circuit electrically coupled to or includes the at least one coil, where the nonlinear resonance circuit is implemented according to claim 22.