Boundary of Continuous Current Mode and Discontinuous Current Mode for IPT Converter

Inductive power transfer (IPT) techniques are attracting widespread attention due to some unique advantages compared to the conventional wired systems. A well-compensated IPT charger should provide the load with constant current (CC), while maintaining nearly unity power factor. To sustain the CC output, the IPT converter should works at continuous current mode (CCM). However, IPT compensation circuit may enter discontinuous current mode (DCM) at some load range. To guarantee the CC output, the load boundary should be derived and the IPT converter should works at CCM. In this paper, the double-sided LCC-compensated IPT prototype is analyzed and the operating frequency to achieve CC output is calculated. The load boundary of the CCM and DCM is derived and the parameters of the double-sided LCC-compensation circuit are designed. Finally, a IPT prototype with output current of 1A is built to verify and exhibit the analysis and load boundary of the IPT systems.