## 4 Experimental Verification of the Proposed Integration Method
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Simulation Values**} & \multicolumn{4}{c}{**Experiment Values**} \\ \hline  & \multicolumn{2}{c}{**DD Coil**} & \multicolumn{2}{c}{**Extended DD Coil**} & \multicolumn{2}{c}{**DD Coil**} & \multicolumn{2}{c}{**Extended DD Coil**} \\ \hline
**Coupling Coefficients** & \(K_{p-s}\) & \(K_{in-s}\) & \(K_{p-s}\) & \(K_{in-s}\) & \(K_{p-s}\) & \(K_{in-s}\) & \(K_{p-s}\) & \(K_{in-s}\) \\ \hline Aligned & 0.2161 & 0.0001 & 0.2163 & 0.0002 & 0.2011 & 0.0083 & 0.2018 & 0.0075 \\ X\({}_{\text{mis}}\)-100 mm & 0.1874 & 0.0012 & 0.1872 & 0.0855 & 0.1802 & 0.0076 & 0.1838 & 0.0833 \\ X\({}_{\text{mis}}\)-150 mm & 0.1360 & 0.0026 & 0.1362 & 0.0683 & 0.1339 & 0.0010 & 0.1355 & 0.0622 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison of simulated and measured values. Figure 10: Experimental input voltage and current waveforms. The proposed system was also verified with the system misaligned state; the results are shown in Figure 12. When the \(Y\)-axis direction is in misalignment by 100 mm, the system output power when the DD coil is used as the compensation inductor is reduced to 1.35 kW, which is 41% of the well-aligned value. Meanwhile, the output power of the system of the extended DD coil (as the compensation inductor) is reduced to 1.39 kW, which is 42.6% of the well-aligned value. Therefore, the results confirmed that the magnetic flux transfer path established between the extended DD coil and the receiver coil does not affect the output power of the system in the \(Y\)-axis misaligned state. However, when the \(X\)-axis direction is in misalignment by 100 mm, the system output power of the DD coil as the compensation inductor is reduced to 2.21 kW, which is 66.7% of the well-aligned value. Furthermore, the output power of the system power of the extended DD coil is 2.97 kW, which is 90% of the well-aligned value; when the misalignment distance is increased to 150 mm, the well-aligned value of 63.6% is still maintained, and the output power is 1.1 kW higher than that of the DD coil. Therefore, it can be confirmed that the proposed extended DD coil compensation inductor can improve the output power of the system in the \(X\)-axis misaligned state. To demonstrate the convenience of the proposed fully integrated coil, an extra inductor with the same inductance extended DD coil was compared with respect to volume and weight as shown in Figure 13, and Table 3 presents the comparison results. Specifically, the proposed extended DD coil is superior to the extra inductor in terms of weight. Additionally, the extended DD coil is located inside the transmitter coil, eliminating the need for additional space and simplifying packaging. During the charging process of EVs, the ferrite core will generate heat and cause power loss, and the system also needs a cooling device; hence, this increases costs. Therefore, using the extended DD coil as the compensation inductor can save space and enhance misalignment tolerance. Figure 11: Experimental power and efficiency in the system aligned state. Figure 12: Comparison of the output power of the compensation inductor for the DD coil and extended DD coil in the system misaligned state: (**a**) \(Y\)-axis and (**b**) \(X\)-axis.