Wireless power transmitter and method of error detection during use thereof
US10673249B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2019 |
| Grant date | Jun 2, 2020 |
| Priority date | — |
| Expiry date | Jun 13, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B5/79
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of detecting a foreign object presence between a wireless power transmitter and a wireless power receiver, the wireless power transmitter comprising a primary coil for transferring power wirelessly to a secondary coil of the wireless power receiver, comprises: transmitting a calibration ping signal; measuring and recording decay time of the calibration ping signal; transmitting test ping signal; measuring and recording decay time of the test ping signal; and determining the foreign object presence if the decay time of the test ping signal is smaller than decay time of the calibration ping signal and if an absolute value of a difference between them is above a threshold. In addition, or alternatively, a self-frequency of a decaying calibration ping signal is measured and recorded; a self-frequency of a decaying test ping signal is measured and recorded; and the foreign object presence is determined if a difference between the self-frequency of the decaying test ping signal and the self-frequency of the decaying calibration ping signal falls outside a predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.