Single-Stage Regulated Resonant WPT Receiver With Low Input Harmonic Distortion

Resonant rectifier topologies would be a promising candidate for achieving simple, compact, and reliable single-stage wireless power transfer (WPT) receiver if not for the lack of good dc regulation capability. This article investigates the problems that prevent the feasibility of single-stage dc regulation in resonant rectifier topologies. A possible solution is the proposed differential resonant rectifier topology, of which the rectifier is designed to have a relatively constant ac voltage, and that phase-shift control is used to achieve relatively good output regulation. Design considerations on the reactive component sizing, magnetic component design, frequency and phase synchronization, small-signal modeling, and closed-loop feedback control design, are discussed. Experimental results verified that the proposed WPT receiver system can achieve single-stage ac rectification and dc regulation while attaining the key features of low harmonic distortion in its ac output voltage, continuous dc current, and zero-voltage-switching operation over a wide operating range.