Affordable Bi-directional Onboard EV Charger

Team: Amaya Francom, Aaron Johnson, Karl Kraus, Hunter Larson, Patrick Owen and Isaac Stoll

Project

CAD image of design
  • Increased number of EVs while charging infrastructure is not always available
  • Bi-directional chargers aid in reducing grid load
  • Project Consists of a two-stage design
  • Utilizes custom wound inductors and transforms to meet specific requirements
  • Affordable components were chosen to help accelerateEV industry adoption
  • This project is compact with an energy density of 2KW per liter
  • This project provided invaluable experience for the teams

System

System Diagram

Methods

Requirement Solution
120/230 VAC Input Full Bridge Rectifier - Active Front End
Nominal 400 VDC Output Series Resonant Dual Active Bridge
1 kW Power Output Phase Shift of the DAB
Bidirectionality Phase Lead and Phase Lag of the DAB
Galvanic Isolation Custom Transformer
2 kW/L Power Density Enclosure to Limit Volume
Power Factor Correction > 0.96 Hybrid High and Low Switching Active Front End
Target Efficiency of 92% or greater Zero Volt Switching, Low Ron Resistance, and Custom Inductors
Galvanic Isolation (Transformer) Custom Transformer Design

Conclusion

The IFEC team attended the semi-finals in San Antonio, Texas. The team is actively awaiting confirmation for finals in Belgium.

Circuit board 1 Circuit board 2
  • Simulation results show proof of concept and sound design.
  • Once the PCB arrives, a full hardware test can be performed to confirm simulation results.
  • The simulations show that an affordable charger is possible, allowing greater accessibility for EVs to reduce grid load.
  • The IFEC team gained experience in magnetic design, circuit design, component selection, thermal regulation, CAD modeling, project organization, and public speaking.
  • A full hardware test and full charger