Application of DC-DC converters in loosely coupled wireless power transmission systems

Inductive loosely coupled wireless power transmission (WPT) system is characterized by heterogeneous magnetic field of the transmitter. The voltage at receiver's output varies with position of the receiver, with design of the receiver's LC tank circuit, and with the load resistance. This paper measures the impact of these three parameters on receiver's output voltage and output power. Paper also evaluates application of low-cost DC-DC converters in such systems. Measurements show that the usage of DC-DC converters results with constant output voltage of the receiver and the maximal efficiency of DC-DC converters ranges from 60 % to 90%.