Data transmission method without additional circuits in bidirectional wireless power transfer system

In the bidirectional wireless power transfer (WPT) system, each power circuit of the transmitter and the receiver part is controlled by different controllers. Therefore, to control and maintain the entire system, the output voltage phase synchronization and data transmission functions between the controllers should be implemented. The communication circuit is normally used to realize them, but this additional circuit increases overall cost of the system. Therefore, this paper presents the data transmission method without communication circuits for eliminating the dedicated circuit in the bidirectional WPT system. Proposed data transmission is implemented by perturbing peak of the fundamental output voltage at the transmitter and monitoring the signal fluctuation due to the perturbation at the receiver. The operation of the proposed method is verified by the simulation result.