Wireless charging system with power level calculation circuit for foreign object detection
US10763706B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 2018 |
| Grant date | Sep 1, 2020 |
| Priority date | — |
| Expiry date | Mar 13, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J50/80
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a wireless charging system, a power-transmitting node (TX) has a transmitter for transmitting power wirelessly to a power-receiving node (RX), and a signal receiver for receiving signals from the RX. During a power-transfer session, the TX accumulates data corresponding to its transmitted power level, detects an end of a received power (RP) packet from the RX, and then identifies a subset of the accumulated data. The TX calculates its transmitted power level using the subset of the accumulated data. The TX extracts a received power level of the RX from the received RP packet and compares its calculated transmitted power level with the RX's received power level to determine a presence of a foreign object. Accuracy of FO detection when packets from the RX are not properly received by the TX is improved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.