Title:
WIRELESS POWER TRANSMISSION DEVICE AND POWER RECEIVING SIDE CURRENT DETECTION CIRCUIT THEREOF
Document Type and Number:
Japanese Patent JP2019162023
Kind Code:
A
Abstract:
To provide a wireless power transmission device capable of accurately adjusting a frequency to a resonance frequency without depending on a coupling coefficient or a circuit constant between a power transmission side coil and a power reception side coil.SOLUTION: A wireless power transmission device includes a dummy coil 4 connected in parallel to a power transmission side coil 3 with respect to a power supply circuit 6 and not magnetically coupled to a power reception side coil 11, and difference current detection means 7 for detecting a difference current between the dummy coil current iflowing through the dummy coil 4 and a primary current iflowing through the power transmission side coil 3, and the difference current detection means 7 detects a current difference (αi-i) for the ratio α=L/Lof inductance Lof the dummy coil 4 to the inductance Lof the power transmission side coil 3. The current difference (αi-i) is proportional to the power receiving coil current i, and the frequency can be adjusted to the exact series resonance frequency fby using the detected value of the current difference.SELECTED DRAWING: Figure 4
Inventors:
KATAOKA YOSHINORI
Application Number:
JP2019042088A
Publication Date:
September 19, 2019
Filing Date:
March 07, 2019
Export Citation:
Assignee:
NIPPON TECMO CO LTD
International Classes:
H02J50/12; H01F38/14
Attorney, Agent or Firm:
Kazuto Ishida