Modeling and analysis of wireless power transmission system via strongly coupled magnetic resonances

There exist some issues in wireless transmission like low efficiency, short transmission distance and so on. The transmission distance of traditional inductive wireless transmission system is in mm level. For electromagnetic radiant wireless transmission system is transmitted through radiation, the transmission efficiency is very low. The majority of research on wireless power transmission system is based on the traditional coupled magnetic model, which ignores the characteristics of resonance coils under different working frequency. Thus, the resonance frequency obtained isn´t able to make the system working with high efficiency. Based on the transmission characteristics of wireless power transmission, this paper establishes the magnetic coupling resonance model, then analyzes and calculates the optimal transmission frequency of wireless transmission system based on coupled-mode theory and resonance theory, namely the work frequency of strong coupling resonance in the system. By using the finite element analysis method, the paper makes experimental verification on the calculated resonant frequency through the CST electromagnetic simulation software, analyzes the transfer characteristics of the system under different load conditions, and the experimental results show that the calculated resonant frequency can make the system work in a high-efficient and strong coupling transmission state. In the last part, the essay conducts certain analysis on the reasons leading to inaccuracy and proposed some methods to reduce residuals. The experiment set up the hardware system of magnetic coupling resonant wireless power transmission, which light the 4 watts LED lamp in the distance of 12cm, and made the wireless transmission of power realized.