Wide-Range Stability of Concurrent Load Regulation and Frequency Synchronization for a 7-Level Switched Capacitor WPT Rectifier

Abstract

Active rectifiers enhance WPT systems via tunability, high efficiency, and low waveform distortion. However, utilizing these benefits requires that two circuit characteristics are managed simultaneously: the switching frequency must be synchronized to the transmitter and the output must be regulated. Furthermore, the fundamental benefit of impedance tunability inherent to the active rectifier necessitates that this dual-objective control problem remains stable over a wide range of operating points. Either control loop can be designed in isolation, and under this premise, this work contributes a closed form derivation for the cross-coupling behaviors in the control architecture for a 7-level switched capacitor WPT system. Finally, regions of attenuated cross-coupling effects are identified and used to experimentally demonstrate wide-range control with stable output regulation and frequency synchronization.