Research on magnetic coupled resonant wireless power transfer system based on low-frequency adjustable electromagnetic metamaterials designed by variable capacitor array

Abstract Traditional low-frequency electromagnetic metamaterials (EMM) exhibit limitations such as fixed functionality and poor application flexibility in magnetically coupled resonant wireless power transfer (MCR-WPT) systems, making it difficult to meet the demand for real-time dynamic regulation of transmission performance. This paper proposes a prototype of low-frequency adjustable EMM based on an 8 × 8 variable capacitor array and constructs a closed-loop control system for MCR-WPT using a class AB power amplifier. The system employs a maximum power point tracking (MPPT) algorithm to achieve dynamic real-time regulation under various operational conditions. Experimental results show that by applying a control voltage of 0 V to 3 V, the capacitance value of the variable capacitor array can be flexibly adjusted within the range of 33.2 pF ∼ 19.3 pF. The designed MCR-WPT system exhibits superior transmission performance under different operating conditions, with the maximum output voltage increasing from 0.505 V to 1.438 V. At the same time, it also has a certain effect on anti-offset. This study holds significant value for advancing the development and application of low-frequency adjustable EMM.