A general design methodology for Dual-Resonant topology with inherent constant current and constant voltage outputs under varying mutual inductance

Abstract

To accommodate the battery charging process in wireless power transfer (WPT) systems, dual-frequency topologies capable of supporting constant current (CC) and constant voltage (CV) output modes have been extensively studied. However, most existing topologies struggle to maintain two output modes and zero phase angle (ZPA) input under varying mutual inductance (MI). To overcome this limitation, this paper proposes a general design methodology for dual-resonant topologies with inherent CC and CV outputs, ensuring that two output modes and ZPA input are maintained across different MI values. The proposed methodology begins by segmenting the topology into three parts, effectively decoupling the compensation parameters from MI, with the mode conversion and resonance of each segment designed independently. The design process first establishes the two output modes, followed by the ZPA input design. To achieve ZPA input, additional parameter constraints and topology compensation are introduced. Moreover, principles for identifying feasible compensation positions and corresponding parameter calculation methods are provided, enabling systematic and efficient topology design. Finally, based on the proposed methodology, an LCCL-LCLC compensated topology is derived. Experimental validation confirms the effectiveness and practical applicability of the proposed design approach, demonstrating its potential for enhancing the performance and reliability of WPT systems.