Spin Up 4-53 - Droop

[iahim]

According to Spin Up, if the droop increases, the generator takes on less load. Why?

The droop is defined as (No Load Speed - Full Load Rated Speed)/Full Load Rated Speed (according to Woodward). Since the Full Load Speed is a rated value, I assume, when you adjust the droop, you raise or lower the No Load Speed. Am I wrong?

Assuming the above assumption is correct, and you have a generator operating at 60Hz, 3% droop, 50% loaded, in parallel with other generator, if you increase the droop from 3% to 4%, the No Load Speed will increase. So the droop line will intersect the 60Hz frequency line to the right of 50%. So the generator will support more than 50% load if the droop increases. Is my theory wrong?

 

[EEpowerOK]

If you draw the droop line slope (negative) and take the reference that when the droop increase it move up the slope (towards the Y axis). The Y axis is the frequency and x axis is the power output. So, as you move up the line the power is getting smaller

 

[iahim]

If you draw the droop line slope (negative) and take the reference that when the droop increase it move up the slope (towards the Y axis). The Y axis is the frequency and x axis is the power output. So, as you move up the line the power is getting smaller

My understanding is that the droop is the slope of the line. You are saying that if you move on the same slope from right to left, the power output is lower. I agree with you there, but if you don't change the slope angle, you are not changing the droop.