A uniform dense coil array structure working at the frequency 13.56 MHz is proposed to enhance the transmission efficiency of wireless power transfer (WPT) systems. The proposed coil array consists of eight identical triangular coils and nested inner and outer driving coils, positioned on a dielectric substrate upper and lower layers. Four of the triangular coils are concentrated at the center of the substrate to enhance the magnetic field at the central position, while the other four coils are located at the corners to ensure uniformity of the magnetic field. Simulation results show that the proposed WPT system achieves an efficiency of 88.5% when fully aligned, 72.4% at a lateral misalignment of 50 mm, and 81.0% at an angular misalignment of 50 \(^\circ \) , all of this higher than the transmission efficiency of conventional coils at the corresponding positions. Additionally, the transmission efficiency remains consistently higher than that of conventional coils within the ranges of lateral misalignment from −45 mm to 45 mm and angular misalignment from \(\theta \) = −50 \(^\circ \) to \(\theta \) = 50 \(^\circ \) .