Synchronous Generator Synch: Incoming Speed > Connected Generators

AI Thread Summary
In parallel operation of synchronous generators, the incoming generator must have a slightly higher speed than the connected generators to avoid synchronization issues. If both generators operate at the same speed upon connection, a phase difference will occur due to differing load responses, leading to reverse current flow and potential activation of the reverse power trip. The new generator will slow down as it takes on load, while the existing generator will speed up as it experiences reduced load. This difference in speeds results in the generators being out of sync, causing operational complications. Proper synchronization is crucial for stable generator performance in a connected system.
smruti
Messages
20
Reaction score
0
in a parallel operation of synchronous generators...while synchronising a new generator to a bus..why the speed of incoming generator should be slightly more than the other generators that are connected to the bus?
 
Engineering news on Phys.org
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.
 
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.
how it will cause phase difference when the speed will be same? can you please elaborate?
 
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?
 
  • Like
Likes Rippetherocker
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?
thank you..
 

Thread 'Underwater piezoelectric sensor array receive sensitivity'

Hi all I have some confusion about piezoelectrical sensors combination. If i have three acoustic piezoelectrical sensors (with same receive sensitivity in dB ref V/1uPa) placed at specific distance, these sensors receive acoustic signal from a sound source placed at far field distance (Plane Wave) and from broadside. I receive output of these sensors through individual preamplifiers, add them through hardware like summer circuit adder or in software after digitization and in this way got an...
View full post »

Thread 'Question about bonding ground and neutral'

I am not an electrical engineering student, but a lowly apprentice electrician. I learn both on the job and also take classes for my apprenticeship. I recently wired my first transformer and I understand that the neutral and ground are bonded together in the transformer or in the service. What I don't understand is, if the neutral is a current carrying conductor, which is then bonded to the ground conductor, why does current only flow back to its source and not on the ground path...
View full post »

Thread 'Following up on the recent thread about Earth Resistance measurements'

I have recently moved into a new (rather ancient) house and had a few trips of my Residual Current breaker. I dug out my old Socket tester which tell me the three pins are correct. But then the Red warning light tells me my socket(s) fail the loop test. I never had this before but my last house had an overhead supply with no Earth from the company. The tester said "get this checked" and the man said the (high but not ridiculous) earth resistance was acceptable. I stuck a new copper earth...
View full post »

Similar threads

Synchronous generator on an infinite bus
Replies
37
Views
6K
Synchronous generator variable speed and constant excitation
Replies
3
Views
2K
ABC reference frame synchronous generator modelling in Ltspice
Replies
1
Views
3K
Induction Generator connected to a standalone Synchronous generator
Replies
12
Views
2K
What Happens to an Induction Generator at No Load and Super-Synchronous Speed?
Replies
14
Views
3K
Lagging or leading synchronous generator
Replies
2
Views
3K
Power grid & generator questions
Replies
46
Views
6K
AC generator output voltage to grid question
Replies
4
Views
2K
Cannot lock reference signal on lock-in amplifier
Replies
5
Views
2K
Issue with energy conversion in synch. machine
Replies
10
Views
2K

Hot Threads

Recent Insights

Back
Top