The multiple parallel pickup modules (MPPMs) are often applied in high-power inductive power transfer (IPT) system for rail transit. However, MPPMs exhibit the phenomena of unbalanced currents and output powers due to the inconsistent parameters. This will limit the output power and deteriorate the system efficiency, more seriously cause system fault. Hence, this paper proposes a simple and cost-effective method to balance currents and output powers by adding small auxiliary transformers (ATs) with turn ratio 1:1 on the pickup side. First, the current distribution is analytically studied under inconsistent mutual inductance and pickup coil inner resistance for the traditional as well as proposed IPT systems, respectively. Then, the efficiency comparison between the traditional and proposed IPT systems is also explored. Moreover, the sensitivity to the capacitance deviation of compensation capacitors for the proposed system is analyzed. Finally, an IPT system with two and four parallel pickup modules is implemented to verify the proposed method. The currents and output powers of the MPPMs are almost equal respectively. The system efficiency is also improved compared to the traditional IPT system.

中文翻译：

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轨道交通多并联拾波模块IPT系统中的电流与输出功率平衡方法


多个并行拾取模块（MPPM）通常应用于轨道交通的大功率感应电能传输（IPT）系统中。然而，由于参数不一致，MPPM表现出电流和输出功率不平衡的现象。这会限制输出功率并恶化系统效率，更严重的是导致系统故障。因此，本文提出了一种简单且经济有效的方法，通过在拾波侧添加匝数比为 1:1 的小型辅助变压器 (AT) 来平衡电流和输出功率。首先，分别对传统 IPT 系统和所提出的 IPT 系统在互感和拾波线圈内阻不一致的情况下的电流分布进行了分析研究。然后，还探讨了传统 IPT 系统和所提出的 IPT 系统之间的效率比较。此外，还分析了所提出系统的补偿电容器电容偏差的敏感性。最后，实现了具有两个和四个并行拾取模块的IPT系统来验证所提出的方法。 MPPM 的电流和输出功率几乎分别相等。与传统的IPT系统相比，系统效率也得到了提高。