Electric-filed coupled wireless power transfer (EC-WPT) technology uses the high-frequency alternating electric field excited between the metal plates of the coupling mechanism as the power transmission carrier to realize the wireless transmission of electric energy. The coupling mechanism of the EC-WPT system has unique advantages such as low cost, light weight, and variable shape. The eddy current loss caused on the surrounding metal conductor is small, the magnetic field interference is small, and it can pass through the metal to transfer energy. However, there is still a lack of corresponding research results on the relationship between the position and number of excitation points of the coupled plates and the system parameters, and how to determine the position and number of excitation points of the plates. In this paper, the coupling mechanism of the key part of the wireless power transmission system is simulated, including the distribution of electric field and current density, and the influence of different excitation point positions and numbers on the system. The simulation results show that the design of multi-voltage excitation access point has a considerable improvement on the energy transmission efficiency of the system.