Abstract:
This paper presents a unique mathematical analysis
of the magnetic field (H-field) forming using coil antennas to
mitigate the lateral misalignment problem in the wireless power
transfer (WPT) system. State of the art emphasizes generating
uniform H-field distribution as a solution to the stated problem
and for that large-sized transmitters are designed to enhance
receiver working region. In this paper, by optimizing the field
forming technique based on derived closed-form analytical expressions, a general non-uniform H-field distribution is proposed
as an optimal solution to the misalignment problem. Through
rigorous analysis, this work proposes a step-wise procedure for
designing the transmitter coil array antenna to generate the
non-uniform H-field distribution. To validate the model, two
planar antenna arrays are designed by following the proposed
procedure. This results in a uniform induced voltage profile under
the misaligned Rx condition, hence, resolves the problem. The
antenna designs are simulated, fabricated, and measured. The
analytical results are found in agreement with the simulated
results and further verified experimentally. The results indicate
that the antennas designed using the proposed method are able
to mitigate the lateral misalignment problem in a wider area of
the receiver region with a smaller transmitter size.
