Tag: S21

Measuring Wireless Power Transfer Efficiency (1)

Transmission efficiency of the wireless power transfer (WPT) system can be measured with a vector network analyzer (VNWA). The following picture shows how we measured the transmission efficiency of this system. The yellow WPT coil in the left side is connected to the port 1 of VNWA, while the blue WPT coil in the right side is connected to the port 2 of VNWA. The resonant frequency of this system is set to be 14 MHz. Therefore, the frequency range in this measurement is between 1 MHz to 27 MHz. The following figure shows the equivalent circuit of this WPT coil. Each component’s values were calculated by analyzing the input […]