An Instant-Setup On-Delay Compensation Scheme Based on Phase Detection for Series-Resonant Wireless Power Receiver with Up-to-4.41% Efficiency Enhancement.

Wireless power transfer (WPT) based on series-resonant secondary (SS) topology is becoming increasingly popular for portable electronic applications [1]–[3]. To enhance the power conversion efficiency (PCE) of the WPT receiver (RX), active diodes with lower forward voltage drop are adopted in rectifier circuit. However, when operating at high frequencies, the propagation delays of the active diodes prevent the power MOSFETs from being turned on promptly (on-delay). As shown in Fig. 1, in SS topology, this on-delay leads to body-diodes conduction (point A to point B), which reduces the PCE.