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Electric Power Generation
Installation and maintenance
5747 en - 2018.10 / a
Dual plate D700
20
4.3.4.1. Loss of power supply
If the power supply fails, switching to the "online" AVR occurs automatically.
4.3.4.2. Power transistor fault
Each AVR has a circuit which monitors the power transistors. If there is a discrepancy between the
transistor command and its action, the "active" AVR switches to "fault" mode and the "online" AVR
switches to "active" mode.
Start
AVR 1 = active
AVR 2 = online
Power supply fault on AVR 1?
Yes
No
Switching:
AVR 1 = fault
AVR 2 = active
No switching
Start
AVR 1 = active
AVR 2 = online
Power transistor fault (IGBT)
AVR active?
Yes
No
Switching:
AVR 1 = fault
AVR 2 = active
No switching