A Gyrator-Based Converting-Splitting Method of Designing Inductive Power Transfer Systems With Constant Current and Constant Voltage Charging

Abstract

In inductive power transfer (IPT) applications, load-independent constant current (CC) charging and constant voltage (CV) charging has become more popular. In a high-order resonant network in IPT systems, there are usually multiple resonant frequencies. Through parameter design, Realizing both the load-independent voltage and current transfer characteristics in the same circuit is possible. In this paper, a gyrator-based converting-splitting method is proposed to realizing CC/CV charge under the zero-phase angle (ZP A) condition for the primary inverter without additional switches. In this method, the circuit model is split into several gyrators after impedance conversion. Soft switching of primary inverters can be achieved over the entire charge process. The system design is experimentally verified on a 2.8 kW prototype of LCC-S compensated IPT system. The efficiency of the LCC-S compensated IPT system is up to 96.3% and 98.4% when the IPT system operating at resonant frequencies that achieve CC output and CV output, respectively.