## 4 Experiment Verification  
It is necessary to confirm the feasibility of the proposed WPT charging systems. To validate the foregoing theoretical analysis results and the proposed hybrid compensation topology model, a 1.1-kW test prototype was constructed, as shown in Figure 14, according to the structure of Figure 10a. The specific parameter settings were presented in Table 1, and were measured by using the LCR meter (IM3536, Hioki). The parameter settings of this experimental prototype provided a CC-output of 11.8 A and a CV-output of 88 V. As indicated in Figure 14, DSP TMS320F28335 was selected in this experiment to control FBI and ACS\({}_{8}\) and \(S_{2}\) composed of SiC MOSFETs (C3M0030090K, Wolfspeed), and Schottky  
Figure 13: Flowchart for the topology parameters design of the proposed WPT charger. diodes (IDW20G120C5B) were used to form the rectifier. Chroma 63200A was adopted to simulate the dynamic loads. In this experimental prototype, the measured parameters of manufactured LCT are presented in Table 2. These parameters met the requirements of the WPT1 standard of SAE J2954 recommended practices. There was a deviation of approximately 1% between the actual measured value and the theoretical value due to manufacturing deviations. The dimensions (length \(\times\) width) of the transmitting-loop \(L_{\mathrm{P}}\) and receiving-loop \(L_{\mathrm{S}}\) were 65 \(\times\) 50 cm and 32 \(\times\) 32 cm, respectively. The transmission distance between the \(L_{\mathrm{P}}\) and \(L_{\mathrm{S}}\) was 15 cm. Litz wire was used to reduce the skin effect and proximity effect. The overall charging curve of the battery is presented in Figure 15a. As shown, in the CC charging stage, the output voltage increased from 24 to 88 V as the equivalent resistance increased from 2 to 7.3 \(\Omega\) (orange line). In contrast to the equivalent resistance, which changed by a factor of 2.6, the charging current changed by only 2.6%, indicating the realization of the CC mode. In the CV charging stage, the output current decreased from 11.8 to 1.9 A as the equivalent resistance increased from 7.3 to 45.9 \(\Omega\). In contrast to the equivalent resistance, which changed by a factor of 6.3, the charging voltage changed by only 5.5%, indicating the realization of the CV-output. Figure 15b presents the measured \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Symbols** & **Symbols** & **Symbols** & **Symbols** \\ \hline \(L_{\mathrm{IN}}\) & 100 V & \(L_{1}\) & 11.51 uH \\ \(f\) & 85 kHz & \(L_{2}\) & 11.48 uH \\ \(C_{\mathrm{F1}}\) & 122.9 nF & \(C_{\mathrm{P1}}\) & 305.7 nF \\ \(C_{\mathrm{F2}}\) & 123.8 nF & \(C_{\mathrm{P2}}\) & 305.9 nF \\ \(C_{\mathrm{F3}}\) & 610.48 nF & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Designed parameters of the proposed WPT charger. Figure 14: Experimental prototype of the proposed WPT battery charger. experimental efficiency of the proposed hybrid compensation WPT systems under the dynamic loads in the total process (blue line). In the CC charging stage, the maximum efficiency of the entire system was 90.9%. When the rated charging voltage value was reached, the WPT charger switched to the CV charging mode. The system efficiency gradually increased from 90% to the maximum value of 91% and then gradually decreased to 85%. The experimental waveforms were scanned by using an oscilloscope (HDO4034A, Teledyne Lecroy). The results obtained under the dynamic loads are presented in Figures 16 and 17. In the CC mode, the charging current \(I_{\text{BAT}}\) was basically constant while the output resistance \(R_{\text{L}}\) fluctuated from 4 to 7 \(\Omega\), as presented in Figure 16, and the charging voltage \(U_{\text{BAT}}\) and AC input current \(I_{\text{IN}}\) increased continuously. In contrast, in the CV charging stage, as shown in Figure 17, when \(R_{\text{L}}\) fluctuated from 8 to 11 \(\Omega\), the charging voltage \(U_{\text{BAT}}\) was nearly unchanged, \(I_{\text{BAT}}\) and \(I_{\text{IN}}\) continued to decrease over time.