Design and optimization of a DISO DC-DC converter for improved misalignment tolerance in RCPT systems

Abstract

A dual-input single-output (DISO) DC-DC converter is proposed to suppress common-mode (CM) currents in laterally misaligned resonant capacitive power transfer (RCPT) systems, reducing shield voltages and electromagnetic interference (EMI) without compromising power-sharing or efficiency. Unlike single-input single-output (SISO) configurations, which enforce a single rectified voltage in a differential system and exacerbate CM currents, the proposed converter independently loads both rectifier outputs, stabilizing shield voltage and enhancing system safety and reliability. Simulations and experimental results validate the performance of the DISO converter over a misalignment range of ±50 % of the capacitive link transmission distance. Simulation results show a 27 dB reduction in CM current on the receiver side and 15 dB on the transmitter side. Experimental measurements indirectly confirm these findings. The DISO configuration also demonstrates the potential to minimize EMI risks. Future work will optimize the experimental system, validate effects on inverter power sharing, and explore enabled misalignment detection methods.