4 ms·
All I'm saying is that the frequency-impedance characteristic of the local system changes depending on active power loading, other nearby generators in or out s
by eigenvector 7y ago
All I'm saying is that the frequency-impedance characteristic of the local system changes depending on active power loading, other nearby generators in or out service, nearby reactors or capacitors in service, etc. So it's conceivably possible that the oscillatory behaviour was more effectively damped both in the modelling cases and in whatever field testing they did. Though if you read the grid code compliance testing report for Hornsea, it's not evident they actually did voltage step change field validation.
If this kind of oscillation was present under all conditions, it would be an oversight to not have caught it in the modelling stage. The level of modelling we have to do in some North American regions for a 50 MW wind farm would catch that kind of behaviour, let alone an 800 MW unit.
- generatorguy 7y agoIndeed when there are large outages is when utilities often find out that the models Don’t quite match reality. One example would be when 1200 MW of generation tripped in the WECC region and they found the effective droop of the system was about 8% instead of 5, and have since mandated that every generator over 10 Mva is tested every 5 years to ensure the equipment still matches the model.