Online Board Charger (OBC) Topologies

I have studied the Online Board Charger topologies being used in the chargers used for charging the electric vehicle. Just wanted to note down the key points that I came across.

When we are talking about topologies used in the EV chargers, it's divided into two parts. The first section is the PFC (Power Factor Correction) Circuit, and the second section is the DC-DC Convertor topology. The PFC is further classified into single-phase and three-phase circuits.

PFC Topology

Single phase

  • Classic boost topology
  • Bridgeless boost topology
  • Interleaved boost topology
  • Totem pole
  • Interleaved Totem pole
  • Neutral point clamped (NPC)

Three phase

  • Two level PFC
  • NPC 3 level PFC
  • Vienna
  • T-type

DC-DC Convertor Topology

  • LLC resonant convertor
  • Phase shifted full bridge(PSFB)
  • Single phase dual active bridge
  • Dual active bridge in CLLC mode
There was a time when I went through each and every Topology and kept everything at my fingertips. I have a good deck of PPT for reference, which has a lot of details about the working of these topologies. Let's see how much I can document in the blog articles.

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