Design of a Low-Profile Receiver of 3.3 KW wireless charger

Abstract

The usage of physical space in an Electrical vehicle is a roadblock to achieving peak performance in wireless charging applications. Components like the receiver, onboard power electronics, etc. have to be arranged in such a way that challenges like bulkiness, power density, thermal management is handled to achieve maximum operating life of these devices and their performance. This becomes more prevalent in heavier vehicles. This thesis explores such possibility of solving this constraint by placing the power electronics on top of the receiver.To start with, different frequency ranges used in Wireless power transmission are discussed, fol­lowed by topologies of the coil and compensation networks. Every topology and network has its ad­vantages and disadvantages. And based on various parameters, a comparison is made.Subsequently, power losses across various components of both the primary and the secondary sides of the Wireless Power Transmission(WPT) are calculated in their worst ­case scenarios. These losses are essential for analyzing the thermal management of the system, as these losses produced by the devices generate heat.A series of thermal models were designed on COMSOL 5.6a to analyze the temperature distributions of these circuits. Starting with a simple model which involves two diodes connected in series to more complex cases like the design of the receiver and finally to the last step which is placing the rectifier on a heatsink atop the receiver. The results are experimentally verified and many conclusions are deduced from them. These results give a better understanding of how heat flows in a system. A Thermal analytical model is designed on LT­-SPICE to a thermal circuit of arrangement of the components in the system.