Input-Series Output-Series Multichannel IPT System for High-Voltage and High-Power Wireless Power Transfer

To realize high-voltage high-power wireless power transfer, an input-series output-series (ISOS) multichannel inductive power transfer (IPT) system is proposed in this article, which is well-suited for high-voltage load and can reduce the transmission loss at the input side. Meanwhile, the number of channels can be adjusted flexibly according to the voltage and power requirement. First, the transmission characteristics of the proposed system are analyzed based on different compensation networks. Then, possible factors that may lead to voltage imbalance are analyzed. The numerical relationship of voltage ratio and parameter offset ratio between different channels is figured out and an improved voltage-sharing principle based on fixed-ratio phase-shift control is proposed. Finally, two down-scale prototypes composed of two channels and three channels are built up to confirm the effectiveness of the proposed topology and voltage-sharing method. The experimental results show that the proposed method can achieve effective voltage sharing under parameter deviation. The output power and voltage of the two-channel system can reach 9.0474 kW and 604.82 V with the dc–dc efficiency being 94%. As for the three-channel system, the outputs get increased to 13.581 kW and 903.3 V with the efficiency maintaining 94%, while the input and output currents remain almost unchanged compared to the two-channel system.