Generally, electric transportation systems are becoming very popular, whether they are e-buses, Electric Vehicles (EVs), or even low-speed EVs. The industry of EVs is emerging as a significant solution for the environmental issues that the Internal-Combustion Engines (ICE) vehicles contribute to. One of the main factors that affect EVs employment is its charging infrastructure. This project aims to design, develop, and implement a 50kW smart fast charger for EVs that withdraws a grid current with a Total Harmonic Distortion (THD) less than 5% according to international standards and Power Factor (PF) more than 0.9. The charger has to be smart by allowing the remote monitoring and control of system parameters, such as temperature, voltage, and current (IoT-based system). The charger is basically a power converter that consists of three stages: AC-DC conversion, Power Factor Correction (PFC), and DC-DC conversion. The methodology followed in this report is by first validating the principle of the design by simulating a 17kW single-phase converter in both CCM and DCM with open-loop and closed-loop operation. Then, it is extended to a 50kW direct three-phase system using a cascaded Boost-Buck converter, and a 50kW phase-modular system using an isolated SEPIC DC-DC converter. Moreover, simulation results showed that for direct three-phase systems, the CCM mode operation has THD of 33% that cannot be corrected by a closed-loop operation. Also, phase-modular active PFC systems perform better than direct three-phase active PFC because of the three switches used in the three phases that handle the three line-currents. A THD of 1.32% and an almost unity PF has been achieved through CCM mode operation in SEPIC-based phase-modular systems. Also, the experimental implementation of scaled-down single-phase boost PFC rectifier in closed-loop operation showed a THD of 3.4%. Conclusions deduced is that SEPIC-based PFC rectifiers outperform Boost-based ones because of its inherent PFC feature.

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