Implementation and evaluation of pre- and post-regulation control with class-e2 wireless power transfer system

This paper presents a closed loop control design for the class-E
²
WPT system with the pre- and post-regulation. In the proposed WPT system, the output voltage is regulated by changing the switch-on duty ratio of the post regulator, whose information is transmitted to the primary side by wireless communication. At the transmitter side, the input current is minimized by changing the switch-on duty ratio of the pre regulator for tracking maximum power-delivery efficiency under the condition that the necessary power is transferred to the receiver side. The experimental results showed that the designed control system is effective for the voltage regulation with keeping high power-delivery efficiency in the class-E
²
WPT system. Experimental results showed that the proposed control scheme achieves the higher efficiency than only the pre- or post-regulation control, which shows effectiveness of the proposed control scheme.