Comment by mschuster91
5 years ago
One case is automated protection systems in the grid detecting a sudden hop of current and assuming an isolation failure along the path - basically, not enough current to trip the short-circuit breakers, but enough to raise an alarm.
This isn't really a thing. Transmission and distribution protection doesn't operate on any kind of di\dt basis, other than those defined by overcurrent, in which case the line trips. A sudden increase in load will just manifest in ACE (area control error) as a load imbalance and be dealt with by increasing generation from the spinning reserve that the balancing authority is required to have on hand.