A Modified LCC-LCC Topology for Mitigating Load and Coupling Dependency on Output Current in Bidirectional IPT-Based Charger

Conventional LCC-LCC compensated Inductive Power Transfer (IPT) systems often experience significant output current fluctuations due to variations in the air gap distance between magnetic couplers, particularly under varying load conditions. These fluctuations challenge applications requiring stable power delivery, such as bidirectional IPT systems. This paper proposes a modified LCC-LCC compensation network in which mutual coupling is intentionally introduced between compensation inductors via specific winding configurations. This approach effectively minimizes output current fluctuations caused by coupling variations, while also ensuring that the optimal load resistance remains independent of the coupling coefficient, enhancing overall system robustness. Additionally, Double D Quadrature (DDQ) magnetic couplers are employed to eliminate mutual inductance in the power path, simplifying the circuit and improving performance consistency. Simulation results confirm that the proposed design reduces current fluctuations across various coupling and load scenarios (from 2.14 A to 3.52 A around a rated current of 2.83 A), with a fluctuation rate of 24%, and achieves a maximum efficiency of 96%.