Wireless power transfer for medical devices
Inventors
Pflug, Hans • Tol, Jeroen • Weijand, Koen
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11534613-B2
Publication Date
2022-12-27
Expiration Date
Abstract
Inductive wireless power transfer systems are provided for medical devices, such as implantable medical devices (IMDs). The systems may comprise a transmitter unit and a receiver unit and may be configured for transferring power and/or signals from the transmitter unit to the receiver unit and/or vice versa. The transmitter unit may comprise an energy source, a transmitter antenna, and a supply line connected in between the energy source and the antenna. The receiver unit may comprise a receiver antenna and a rectifier output. The transmitter antenna and the receiver antenna may be configured to provide a wireless power transfer link. The supply line may comprise a virtual resistance unit, which may be configured to provide a virtual resistance, which may be determined such that the rectifier output provides a substantially constant or less varying charge current over a predetermined distance range, for a large range of implant depths.
Core Innovation
The invention describes a method of performing wireless power transfer for a medical device by transferring power from a transmitter unit to a receiver unit. A virtual resistance unit provides resistance in the supply line, and the transmitter antenna generates a modulated magnetic field received through the receiver antenna. The receiver unit generates a charging current that is substantially constant or has reduced current variation as the distance between the antennas varies.
The described problem is variation in charging current as the distance between the transmitter antenna and receiver antenna changes during power transfer. The method addresses this variation by providing resistance in the transmitter supply line through the virtual resistance unit. The document also describes resonant inductive transfer and identifies transmitter-side circuit components and charging a battery of an implantable medical device as refinements.
Claims Coverage
The provided relevant claims identify one independent claim, claim 1, with one main inventive feature.
Wireless power transfer with reduced charging-current variation
The claim provides a charger current through a supply line to a transmitter antenna whose distance from the receiver antenna may vary, provides resistance in the supply line by a virtual resistance unit, and generates a modulated magnetic field received by the receiver antenna. The receiver unit generates a charging current that is substantially constant or has reduced current variation with respect to the varying distance.
The independent claim centers on using a virtual resistance unit in the transmitter supply line to reduce charging-current variation as antenna separation changes. Dependent claims specify resonant inductive transfer modes, transmitter-side circuit components, and charging a battery of an implantable medical device.
Stated Advantages
Reduced variation in the charging current as antenna separation varies.
Reduced thermal dissipation.
Reduced need for wireless feedback.
Documented Applications
Wireless charging of a battery of an implantable medical device.
Interested in licensing this patent?