Qi (inductive power standard)

Qi ( Chinese word for " life energy", pronounced: [ tʃi ː ] ) is a proprietary standard of the Wireless Power Consortium for wireless energy transfer by electromagnetic induction over short distances.

The standard is intended to ensure interoperability with chargers. For example, several mobile phones can use the same charging stations (including the Nokia Lumia 920, Nexus and Nexus 4 5).

Technology

Q using a resonant inductive coupling between the transmitter and receiver. Transmitter and the receiver exchange data in order to ensure optimal energy transfer. The transmitter modulates doing the sending field. The receiver uses an RFID similar technique to transfer data to the transmitter.

Specifications

  • Transmission frequency: 110-205 kHz ( long wave)
  • Operating voltage of the transmitter: 19V, compatible with many chargers for six-cell lithium -ion batteries
  • Transmitted power: 5 watts (low power ) or 120 watts ( Medium Power )
  • Data transmission between the transmitter and receiver with two kilobits per second.

Benefits

  • Instrument must be placed
  • No wear on the plug contacts on the device
  • By standardizing charger and have come to be loaded device is not from the same manufacturer
  • Along with this is theoretically sufficient a charger for more equipment to be powered

Disadvantages

  • During the energy transfer, the devices must remain in close spatial contact. For example, using a mobile phone while charging is therefore hardly possible. Some Qi chargers, such as the Google Nexus 5, use magnets to hold the charger to the device.
  • The efficiency of an inductive energy transfer is always worse than when using a cable - that is, the energy consumption is higher and the charging rate is actually lower.
  • Qi chargers are currently significantly more expensive than conventional chargers.
Longwave
666551
de