Complex Imaginary (version 2011) Exam 1, Problem 30

[Hazard level]

This is a problem on finding the Maximum Power Output for a question generator. They use a formula

P=3*Vphase*Vinternal / Xsynchronous

I'm a little confused as to Why the solutions use this problem. Can anyone explain?

Thanks!

 

[TWJ PE]

This is a problem on finding the Maximum Power Output for a question generator. They use a formula

P=3*Vphase*Vinternal / Xsynchronous

I'm a little confused as to Why the solutions use this problem. Can anyone explain?

Thanks!

Will you post the problem?

 

[DK PE]

Both Wildi and Stevenson have this relationship.. from Stevenson (Elements of PSA 4th ed):

P =((V sub term x E sub g) / X sub g )  typically times sin Pangle

Since this is on a per-phase basis if the voltages are given in phase voltages you have 3X

And to maximize in theory you set sin Pangle = 1

Just to get a good feeling on units, it is analogous to P = V^2/R as far as units go...

 

[Hazard level]

DK PE, Thanks for explaining this solution. The analogy of P = V^2/R is very helpful and makes sense!