The discussion revolves around the synchronization of synchronous generators during parallel operation, specifically addressing why the incoming generator's speed should be slightly higher than that of the connected generators on the bus. The focus is on the implications of speed differences on load sharing and phase alignment.
Participants generally agree on the necessity of differing speeds for proper synchronization, but there is some repetition in the explanations provided, indicating a lack of consensus on the clarity of the initial points made.
The discussion does not resolve the nuances of how exactly the phase difference manifests or the precise conditions under which synchronization can be achieved, leaving some assumptions and details unaddressed.
how it will cause phase difference when the speed will be same? can you please elaborate?Rippetherocker said:Because as soon as the generator is connected it will take some load and will try to slow down and the already loaded gen. will try to speed up. If both had the same intial speed this will result in a phase difference after connection. A reverse current will flow into the new gen. and activate the reverse power trip.
thank you..FOIWATER said:The speed will not be the same. When the generator is connected it will provide power to the system and the electrical counter torque on the shaft won't match the input mechanical torque. The machine will slow down. The other machine will speed up, since it takes less load now. With them running at different speeds they will be out of synch. That causes the phase difference. I didn't really add anything to the first response but I think he is pretty clear. Does it make sense?