Reduced Active Switch AC to DC Rectifier with High Frequency Isolation for Electric Vehicle Chargers Conference Paper uri icon


  • © 2016 IEEE. This paper presents a reduced active switch count push-pull based DC fast charger for electric vehicles. The proposed system takes a 3-phase utility line voltage and produces a high frequency (HF) AC link employing only two active switches. A 5-limb HF transformer, in zig-zag connection, is employed for isolation. The primary side of the transformer is connected to a clamp circuit and two active semiconductor devices which provide a 3-phase HF AC link. The secondary side of the transformer is connected to a twelve pulse rectifier to achieve AC to DC conversion. The output of the rectifier is then interfaced to an electric vehicle's battery bank. The advantages of the proposed system include low active switch count, simple control strategy, and high input current quality. Furthermore, employing zig-zag connection in the secondary side helps to balance transformer leakage inductance. A design example rated at 50 kW charging a 500V battery is presented. Mathematical analysis and simulation results demonstrate the performance of the proposed system. Experimental results, with a medium frequency zig-zag transformer, at 1.6 kW validate the operation of the system.

author list (cited authors)

  • Sandoval, J. J., Member, T., & Fellow, P. E.

citation count

  • 1

publication date

  • March 2016