Power and efficiency of 2-D omni-directional wireless power transfer systems

This paper presents a mathematical analysis on 2-dimensional omni-directional wireless power transfer. It is shown that with the use of current control in the transmitter coils, magnetic field vector can be generated to point at all directions in a 2-dimensional sense. The theory allows the equations of the total input power and output power of the system to be determined at all angles of input magnetic field vector. Mechanisms for determining the load positions and directing wireless power them efficiently are proposed and practically realized. The theory has been verified with practical measurements.