We studied the effects of the phase and intensity of multiple coil currents in a wireless power transfer system using resonant magnetic coupling. Resonant magnetic coupling is regarded as one of the most promising methods for mid-range wireless charging systems. For mid-range charging, the charging device can assume various positions and postures, and some of the conditions make wireless charging difficult. To solve this problem, we propose a method to control the phase and intensity of multiple coil currents. By performing numerical simulations using an equivalent circuit model and electromagnetic analysis, we confirmed that it had the desired effect.