Analysis of Parallel Output Characteristics of Dynamic IPT System and Design Method of Current Sharing Parameters

The dynamic induction power transfer(IPT) system, with multiple pickup modules parallel output, improves the power transmission capability of the system and is suitable for long rail transmission structures. It has broad application prospects in high-power applications. However, due to the sight differences in parameters between the pickup modules and the dynamic operation of the modules, there may be imbalanced current distribution of the pickup modules in the actual application, which even causes overcurrent damage to the pickup modules. Starting from the mathematical model of LCC-S, the output volt-ampere characteristics and load distribution characteristics of the pickup module are derived, the influence of pickup parameters on current distribution under different compensation states is analyzed, and a secondary side detuning compensation scheme is proposed. A parameter design method for the detuning coefficient is provided, utilizing the adjustment of the secondary side parameters to achieve approximate current sharing control for each module. Finally, an experimental prototype with three pickup modules output in parallel is built. After applying the proposed detuning compensation method, the maximum current ratio between modules is reduced from 13.02 to 1.3. The test results are consistent with theoretical analysis, proving the correctness and effectiveness of the scheme.