Analysis of dynamic wireless charging using tunable self-oscillating method

Abstract

ABSTRACTIn this paper, Tunable Self-Oscillating Switching (TSOS) technique for Dynamic Wireless Charging (DWC) of Electric Vehicle (EV) is investigated. TSOS is a suitable option for DWC, which has parameter variation and requires fast frequency tracking. The system consists of a high-frequency full-bridge inverter, a series–series compensated loosely coupled transformer that is created by Unequal Double D (UDD) coils and a Li-Ion battery as the load that is connected to the output of the full-bridge rectifier. To achieve high efficiency and energy transfer and realise zero voltage switching, the phase of total impedance in steady state condition is investigated. To limit the overshoot of current in the system, a variable phase control method is proposed. Also, an investigation on the proper point to start the charger is performed to decrease the overshoot of current and increase the efficiency. Using this method, overshoot of current could be limited to 50% and energy efficiency could be at least 92.68%. To analyse this method, simulation is done in the Simulink/MATLAB, and to verify the results, a laboratory prototype is implemented.Abbreviations:TSOS: Tunable Self-Oscillating Switching; DWC: Dynamic Wireless Charging; EV: Electric Vehicle; DD: Double D; UDD: Unequal Double D; IPT: Inductive Power Transfer; CT: Current Transformer; MCU: Micro Controller Unit; SOS: Self-Oscillating Switching; ZVZCS: Zero Voltage and Zero Current Switching; EMI: Electromagnetic Interference; SS: Series–Series; PLL: Phase-Locked Loop; DC: Direct Current