Study and Design High-Frequency Resonant Inductive Power Transfer for Application of Wireless Charging Electric Vehicles

This paper explains about the design of wireless power transfer using resonance circuit or called Inductive Power Transfer (IPT). IPT has divided into three parts AC-AC converters, a magnetic coupling circuit, and AC-DC converter. AC-AC converter parts will change the system frequency to high frequency. Besides that, this converter has a current controller to make sure the current that goes to primary side not too high. The average efficiency of AC-AC converter is 85%. Also, at magnetic coupling, a study was conducted to examine the relation between misalignment coils and power transfer efficiency, between misalignment coils and coupling coefficient, as well as the relation between air gap and coupling coefficient. A 3D modeling is done using Finite Element Method (FEM) with JMAG. At the 50-kHz resonant frequency, the results show that the power transfer efficiency decreased significantly when the misalignment between the two coils reached 160 mm or more, between misalignment with efficiency has a negative correlation, the relation between the misalignment with coupling coefficient has negative correlation, and the relation between the air gap with coupling coefficient also has negative correlation. And the last part is the AC-DC converter circuit with charging regulator used. The AC-DC converter consists of a series of rectifiers, buck converters, and controls used in battery charging. The simulations were performed to study the battery charging scheme as well as the value of the parameters designed using PSIM and Matlab Simulink software to the voltage change and the state of charge (SOC) of the battery.