Electronic Crowbar Protection


#1
  • SCR has high surge current ability.
  • SCR is used in electronic crowbar circuit for overcurrent protection of power converter.
  • In this protection, an additional SCR is connected across the supply which is known as ‘Crowbar SCR’.
  • Current sensing resistor detects the value of converter current.
  • If it exceeds preset value, then gate trigger circuits turn ON the crowbar SCR.
  • So the input terminals are short-circuit by SCR and thus it bypass the converter over current.
  • After some time the main fuse interrupts the fault current.