Comparison of Low-Voltage AC and DC Distribution Networks for EV Charging

The increasing penetration of electric vehicles (EVs) in current and future transport fleets imposes significant loading on the existing power grids. Moreover, dc is experiencing renewed interest with rapid growth in electronic loads, the move towards renewable energy sources (RES) and distributed generation, and advances in power electronics technology. The next generation ‘Smart Grids’ need to consider these trends. As a component of the smart grids, low voltage dc (LVDC) distribution has been widely proposed to efficiently enable these changes. This work investigates LVDC for EV charging at residential, commercial and public charging station levels. Load profiles for EV charging are developed and used together with a model LVDC system to compare its performance to a conventional ac system.