Load and Mutual Detect Methods for Omnidirectional Wireless Power Transfer Systems Based on Third Harmonic Analysis

Wireless Power Transfer system (WPT) can transmit energy in either an omnidirectional or directional manner. Currently, directional power transmission is a hot research topic due to its higher efficiency. To achieve directional energy transfer, accurately detecting the energy requirements of the load and its relative position becomes crucial. In this paper, we designed a load detection method based on third harmonic analysis. By analyzing the third harmonics of voltage and current at the primary side, we can precisely obtain information about the load resistance and position. A 2-D WPT system is established in ANSYS, and simulations provide inductance values at different positions of the receiving coil. Additionally, a simulation model is constructed in MATLAB to validate the feasibility of the third harmonic analysis method. The experimental results demonstrate that utilizing third harmonic analysis for load detection in WPT systems is feasible in most cases, with results exhibiting high accuracy.