We have recently had a damage of a MV frequency drive (4,16 kV, 1500 kW). The converter is a three stage MV converter with a DC link voltage of 2,4 and 6 kV voltage.
The damage has been located to the DC link dry capacitor at 6 kV in phase L3.
Two theories could explain this damage:
1) Component failure
2) Malfunction of the pre-charging circuit. (Worst case the rated DC link voltage could be increased by a factor 2)
It it possible to determine if the damage is caused by 1) or 2) ?
The damage has been located to the DC link dry capacitor at 6 kV in phase L3.
Two theories could explain this damage:
1) Component failure
2) Malfunction of the pre-charging circuit. (Worst case the rated DC link voltage could be increased by a factor 2)
It it possible to determine if the damage is caused by 1) or 2) ?
