Impact of Layer Spacing on a $3 \times 3$ Layered DD Coil Array for Efficient EV Wireless Power Transfer

For uses like charging electric vehicles, wireless power transfer is a potential technique. With an emphasis on intra- and inter-layer coupling effects, this study examines the performance of a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$3 \times 3$</tex> array of 3-layered Double-D coils. The study checks the coupling coefficients and mutual inductance by adjusting the lateral (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$d_{x}=10 ~\text{mm}$</tex> to 20 mm) and vertical (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$d_{z}=20$</tex> mm to 100 mm) spacings. The findings demonstrate improved inter-layer coupling, reaching a mutual inductance of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$48.75 \mu \mathrm{H}$</tex> and a maximum <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$k=0.488$</tex> at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$d_{z}=20 ~\text{mm}$</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$d_{x}=10 ~\text{mm}$</tex>. At <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$d_{z}= 100$</tex> mm, performance decreases as spacing increases (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$k=0.142$</tex>). This study emphasizes how crucial perfect alignment and layered designs are to scalable and effective wireless power transfer systems. In order to develop high-power wireless power transfer technologies, future research will concentrate on optimization and further extending the array.