An Optimized Power-Efficiency Coordinated Control Method for EVs Charging and Discharging Applications

Recently, bidirectional wireless power transmission (BD-WPT) technology has been increasingly used in electric vehicles (EVs) charging and discharging applications to realize interactive energy feedback between EVs and the power grid. Although the efficiency of BD-WPT system has been impressively improved, it still heavily relies on complex control methods. This article proposes a simple but effective control method to achieve maximum efficiency with zero reactive power. Specifically, a resonance judgment and phase synchronization network is employed to ensure the resonance performance and synchronization of the bilateral control signals, which realizes the stead autostarting of the secondary side and guarantees the disentanglement between power control processes as well. With the help of voltage ratio design and symmetric phase-shift between bilateral inverters, the optimization efficiency is well achieved. The results of the experiment and simulation match well, showing the effectiveness of the proposed method in this article.