Hello there!

As a project, I did the power flow for a certain system, and I got the results perfectly correct!

Now the thing is, we have one bus (bus 2) that exceeds the voltage limits +-5% of 1 p.u.

in the given data, we are given a capacitor (susceptance 0.3 p.u.) that we can use only on bus 2, in order to control the exceeding voltage.

What I used was, Q = |V|^2 * B (V here is voltage on bus 2, and B=0.3, the susceptance) and I came up with a value of Q, that when injected this amount in the system, the voltage on bus 2, and all the voltages are now inside the permissible limits!

But when referring back to the professor, he said that this is not the purpose of the control he wants! He wants us to know how much Q is needed to be injected in the system, so we can know how much of the 0.3 susceptance we are going to use!!

I couldn't find any other way to know that Q but trial and error! I mean if we can know the Q needed, what is the use of the power flow then??

can anyone help on this plz! Thank you

 

Mariachy... the I believe th iterative procedure is what your Prof wants you to use!

Regards, Phil Corso

 

Well Phil, thank you first, and 2nd, Do you mean by iterative solution, to try all the values of the susceptance from 0 to 0.3?

Regards,
Mariachy

 

Mariachy... No! Obviously I can’t solve it for you, but...

You must have already developed the expression for power transfer between buses 1 and 2 for a specific condition, i.e., P1, Q1 at bus 1, and P2, Q2 at bus 2! Surely the iterative procedure was used to calculate bus 2 from the given parameters. Doesn’t the addition of B at bus 2 change Q2?

Phil

 

Sure it Does! and that is exactly what I did! after finding Ps and Qs with the iterative procedure, I added the B at bus 2, and Q2 changed, and V2 was inside the permissible limits again!

that's what I said in the first place! but I guess I didn't explain myself right

But the problem is, the Prof doesn't want us to add all the B, or to try different values of it until we succeed. he wants us to calculate how much Q is needed, and upon this Q we should find how much of B we should use!! that's what I can't figure out how!

 

Mariachy... I am pretty much old fashioned; I prefer face-to-face (so-to-speak) communication. So, send me your full name, your school, your location, and the work you have done, thus far!
I can reciprocate by sending an abridged or full version of my Professional Background!

Regards, Phil Corso