POWER FACTOR CORRECTED HIGH GAIN LUO CONVERTER BASED BATTERY CHARGER FOR EV

Abstract

One of the most important aspects to research and improve for Electric vehicles is batteries and chargers. Firstly, this thesis work deals with the lower system stresses for power factor correction at the front-end of an electric vehicle in a high step-up gain Luo converter, connected in series with a flyback converter for the battery charger. This deduction in switch voltage is produced in the conventional Luo converter by installing one switch and splitting the input inductor i.e., high gain Luo converter. While comparing the conventional Luo converter with the high gain Luo converter, for producing the same DC link voltage high gain Luo converter operates at a lower duty ratio due to the input switching inductor design. This is suitable for high-power EV chargers since the switching voltage and current stresses are massively decreased. Secondly, this thesis work deals with the basic operation of the half-bridge LLC resonance converter for battery charging in resonant mode, step-down mode, and step-up mode. In this, we used the PI and PFM controller for producing the control frequency spectrum and for converting the control frequency signal into a pulse respectively. By comparing currents in resonance mode, the peak current of resonant current and magnetizing current is largely due to this primary side conduction losses increase in boost mode. In all three modes, the resonant mode provides excellent results. Finally, improvements have been implemented to boost efficiency and power factor. the power factor correction of LLC resonant DC-DC converter for battery charging of EVs. Under the load and supply voltage variations, steady-state topology is evaluated. For various supply voltage, power factor and THD% are computed, resulting in a low value of THD%. Due to this, we achieved a smooth sinusoidal supply current. In this, we determined that charging the battery near the resonance frequency is the best approach. Mention all the converters have been simulated in MATLAB/SIMULINK based on the model and controlling algorithm.