Patent · US Active

Methods and systems for measuring power in wireless power systems

US9784777B2 · kind B2 · utility

0Cited by
5References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 24, 2014
Grant dateOct 10, 2017
Priority date
Expiry dateMay 12, 2036

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K2005/00286
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The invention provides a method and system for precisely measuring AC power and detecting load impedance using a precise analog front-end, zero-crossing detectors, and a phase detection system capable of extracting precise phase information from the sensed voltage and current measurements. More particularly, the invention provides an apparatus, comprising a transmit circuit configured to generate a wireless field via an antenna for transferring charging power to a receiver device, for determining a phase difference between a first signal and a second signal. The apparatus further comprises a phase detection circuit to output a phase signal indicating a duration of a phase offset between a time-varying voltage and a time-varying current of the transmit circuit. The apparatus further comprises a capacitor configured to receive a variable current from a current source for the duration of the phase offset between the time-varying voltage and a time-varying current.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.