Wireless charging system with object detection
US10511197B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 31, 2018 |
| Grant date | Dec 17, 2019 |
| Priority date | — |
| Expiry date | Jan 31, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J50/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A wireless power transmitting device transmits wireless power signals to a wireless power receiving device. The wireless power receiving device has a wireless power receiving coil in a resonant circuit that resonates at a wireless power receiving circuit resonant frequency. The wireless power transmitting device has coils. The coils are supplied with a drive signal in bursts to detect external objects. Measurement circuitry includes an oscillator for supplying the drive signals and a peak detector and analog-to-digital converter for gathering measurements on the coils to which the drive signals have been supplied. Rate-based-filtering is applied to output signals from the analog-to-digital converter to distinguish between temperature drift effects and object placement effects. The frequency of the drive signals is slightly greater than the wireless power receiving circuit resonant frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.