Abstract:
The structure of multiple parallel pickup modules is often applied in the high-power inductive power transfer(IPT)system. However, the inconsistent parameters of multiple parallel pickup modules may result in unbalanced current and output power between pickup modules, which reduces the system efficiency and may cause the system failure due to the module overcurrent in severe cases. To solve this problem, this paper proposes a method to balance the current and the output power of multiple parallel pickup modules by connecting the compensation capacitors of all pickup modules in parallel. First, the characteristics of the topologies of the conventional IPT system and the proposed IPT system are analyzed. Then, the influence of the mutual inductance, the self-inductance and the inner resistance of the pickup coil on current distribution and system efficiency is analyzed. Finally, the effectiveness of the proposed method is verified by an experimental platform of the IPT system with four parallel pickup modules. The experimental results show that the current and the output power of multiple parallel pickup modules are almost equal when adopting the proposed method, and the system efficiency is improved by 2.21% compared with the conventional IPT system.