A Multimode Reconfigurable IPT Topology for High-Efficiency CC/CV Wireless Charging of AGVs over a Wide Load Range

Constant-current/constant-voltage (CC/CV) charging requires an inductive power transfer (IPT) converter to maintain the desired output characteristic and high efficiency over a wide range of operating-point load conditions. To address this challenge, this paper proposes a multimode reconfigurable IPT topology for high-power wireless charging of automated guided vehicles (AGVs). The topology coordinates reconfiguration between LCC–LCC and LCC–S compensation networks with full-bridge/half-bridge operation on both the inverter and rectifier sides, establishing three operating modes for low-load CC, higher-load CC, and high-load CV charging without a cascaded output DC–DC converter. A hybrid mode-switching strategy is further developed: the Mode 1/2 boundary is selected at the equal-efficiency point to preserve wide-range efficiency, whereas the Mode 2/3 boundary is selected at the equal-power point to reduce the CC-to-CV transition-power discontinuity. Experimental results obtained with resistive load banks over 3–144 Ω show that the hybrid strategy maintains a measured power-stage DC–DC efficiency of 91.72–94.95%. Compared with fixed single-mode operation over the same range, the hybrid strategy increases the minimum measured efficiency from 85.70% to 91.72%, an improvement of 6.02 percentage points. The prototype achieves a maximum output power of 15.26 kW at 94.71% efficiency, demonstrating the feasibility of the proposed reconfigurable approach for high-power, wide-load-range AGV wireless charging.