GaN OBC design reduces BOM and increases power density over SiC

Using GaN transistors in an 800V OBC is an innovation that gives this 11kW/800V design its edge.

GaN OBC design reduces BOM and increases power density over SiC
The OBC combines a three-level flying capacitor topology for a bridgeless totem-pole PFC structure and dual active bridge in the AC/DC and DC/DC, respectively.

The GaN transistors, in the three-level topology, reduce the Transistor voltage stress to half and allow the 650V GaN to be used in this and many other 800V applications.

Key Features of the OBC design

  • 36% higher power density compared to silicon carbide
  • AC/DC stage peak efficiency>99%, DC/DC stage peak efficiency>98.5%
  • Smaller total Semiconductor power loss
  • Minimized gate ringing, lower noise and ringing during switching transitions
  • Improved thermal performance by employing an IMS interface

GaN power semiconductors increase the efficiency of the OBC by reducing switching losses and power dissipation during operation.

This improved efficiency reduces power losses during EV charging, making the OBC significantly more energy-efficient and cost-effective.

For instance, the solution’s higher efficiency reduces the complexity and cost of the cooling system design. The compact and highly efficient design helps reduce the overall size and weight of the OBC, freeing up space and weight that can be allocated to other areas of the EV design.

For more information see here.