Electric Vehicle (EV) Fast DC Charging
Fast and Ultra-Fast Charging
DC chargers convert the AC power from the grid into DC power, delivering it to the charging port of the electric vehicle to charge the batteries. DC charging mode bypasses the On-Board Charger (OBC) on the vehicle used for AC charging (typically ranging from 1.4 to 22 kW). DC charging allows for higher charging power ratings that range from above 20 kW to more than 400 kW. The higher power of ‘fast’ and ‘ultra-fast’ DC chargers drastically reduces the charging times. Although there is no standard definition, ‘fast’ charging is considered below 80 to 100 kWs. With EV fuel economy ranging from 12 - 20 kWh/100 km, ultra-fast chargers can add 100 kms of range in less than 2 minutes, respectively. Charging stations are a particular type of EV charging infrastructure, predominant nowadays along highways and offering multiple ‘ultra-fast’ chargers. Such facilities require a dedicated high voltage transformer to source power beyond 1 MW from the grid.
Fast DC Charger Architecture
DC chargers consist of an AC/DC stage and a subsequent DC/DC stage, converting AC to DC power from the grid and adapting it to the batteries’ required voltage and current levels. Higher power DC chargers, typically built with a modular approach, have power blocks of 15 – 75 kW (and above) stacked together in a single cabinet. In general, output voltages of DC chargers range from 150 volts to north of 1000 volts and cover both the 400 Vand 800 V standard battery levels. Power system designers may optimize the batteries for the higher or lower voltage battery levels.
Fast DC charging requirements
The growth of the EV charging market is accelerating, and the requirements for this infrastructure are rapidly evolving. Increasing peak powers beyond 350 kW, extremely high performance with 96% efficiencies are becoming standard. Finally, compactness, robustness, and enhanced reliability are also imperative for such solutions widely deployed across diverse geographical areas and environmental conditions. Moreover, the right cost level should also be met. Developing such a system requires broad application expertise, alternative solutions to optimize the design, and reliable and robust underlying power technologies. ON Semiconductor is a value-added partner for EV charging solutions and is helping to address these needs effectively.
Optimize Your Design, Speed Up Development of Fast EV Charging Systems
Our leading silicon-carbide (SiC) technology and continuous innovation in packaging solutions help simplify the design process of EV chargers. With a comprehensive portfolio of discrete power and analog solutions, protections, sensing, and connectivity, ON Semiconductor offers high-quality components to tailor the system to your needs. Our system expertise has been fostered over the last 20 years while bringing together all these technologies to deliver well-rounded solutions.