Wireless energy transfer with variable size resonators for implanted medical devices

A power source for wirelessly providing power to a wireless receiver of an electrically powered medical device, the power source comprising:

• a power supply, the power supply configured to supply power at a rate sufficient to charge the battery of a medical device;
• and
• a first electromagnetic resonator coupled to the power supply and having a mode with a resonant frequency ω1, an intrinsic loss rate Γ1, and a first Q-factor Q1=ω1/2Γ1, the first electromagnetic resonator housed in a housing configured to be disposed remotely from the medical device;
• wherein the first electromagnetic resonator is configured to be wirelessly coupled to a second electromagnetic resonator within the medical device and coupled to a load associated with the medical device to provide non-radiative wireless power to the second electromagnetic resonator, the second electromagnetic resonator having a mode with a resonant frequency ω2, an intrinsic loss rate Γ2, and a second Q-factor Q2=ω2/2Γ2;
• wherein the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance;
• and
• wherein the square root of the product of the respective Q factors is greater than 100.

A medical device wireless power system, comprising:

• a power supply, the power supply configured to supply power at a rate sufficient to charge the battery of a medical device;
• a first electromagnetic resonator coupled to the power supply and having a mode with a resonant frequency ω1, an intrinsic loss rate Γ1, and a first Q-factor Q1=ω1/2Γ1, the first electromagnetic resonator housed in a housing configured to be disposed remotely from the medical device;
• a load configured to power the medical device using electrical power;
• and
• a second electromagnetic resonator adapted to be housed within the medical device and configured to be coupled to the load, the second electromagnetic resonator having a mode with a resonant frequency ω2, an intrinsic loss rate Γ2, and a second Q-factor Q2=ω2/2Γ2;
• wherein the first electromagnetic resonator is configured to be wirelessly coupled to a second electromagnetic resonator within the medical device to provide non-radiative wireless power to the second electromagnetic resonator;
• wherein the area circumscribed by the inductive element of at least one of the electromagnetic resonators can be varied to improve performance;
• and
• wherein the square root of the product of the respective Q factors is greater than 100.