Reflected Impedance Based Maximum Output Power Monitoring for MCR- WPT

This paper proposes a magnetically coupled resonant wireless power transmission maximum output power monitoring method based on reflected impedance allowing to solve the problem of large fluctuation of system output power due to the uncertainty of the position of the receiving coils in the conventional wireless power transmission system. The expression of the reflected impedance of the transmitting loop function of the transmission distance is first derived according to Kirchhoff's voltage law. The relationship between the reflected impedance and the maximum output power is then obtained. Afterwards, a simulation model is developed using Simplorer and Maxwell. When the position of the receiving coils changes, the transmitting coils are adjusted to the optimal transmission position by monitoring the reflected impedance, which allows the system to maintain the maximum output power. Furthermore, an experimental model of wireless power transmission is developed. Several experiments are conducted at different distances between the two coils. The proposed reflected impedance monitoring method can make the system always function at the maximum output power.