Stability Analysis of Wireless Power Transfer System Based on Extended Describing Function

Stability analysis of wireless power transfer(WPT) system is complex due to the nonlinear nature. Whereas the stability can be studied by linearizing about the operating point, the modeling of WPT systems poses serious challenges. A general method for stability analysis of WPT system is presented in this paper based on extended describing function(EDF) method. An LCC-S compensated WPT system is considered as case study. It is demonstrated that the stability boundaries can be precisely evaluated by the proposed method, despite the nonlinearity is introduced. Simulation and experimental results are provided to confirm the effectiveness of the proposed analysis.