Power Transfer from 400V Charging Piles to 800V Electric Vehicles Using Motor Winding and Inverter

Range anxiety is one of the main problems for electric vehicles (EVs) due to low battery power density and low charging speeds. The charging speed can be improved by increasing the charging power. The maximum charging power can be increased by raising the battery voltage level from 400V to 800V. However, if the number of new 800V DC fast charging piles cannot increase quickly, charging will become a new problem for 800V EVs. To solve this problem, a method is proposed to allow the 400V charging station to charge the 800V EV. The motor winding and inverter are used to form a boost converter that connects to the 400V charging station through the DC charging port of EVs. With one additional switch, the proposed method can be compatible with 400V and 800V charging piles. The proposed method is verified by simulation and a 500W laboratory prototype.