Dear Ray,
Thank you for your response.
I resolved the problem with the error message regarding dispatchable loads.
In addition, I would like to ask you and clarify some calculations that I make
by extracting data from Matpower.
1) I use the following commands to calculate the bus addmitance Ybus matrix and
impedance Zbus matrix:
[i2e,bus,gen,branch]=ext2int(bus,gen,branch);
[Ybus, Yf, Yt] = makeYbus(baseMVA, bus, branch);
Zbus=1./Ybus;
The values of the matrixes are in pu, isn't it?
2) After that I am interested in computing the shunt addmitance ysh of π
equivalent circuit of a line j->k in pu.
bs=mpc.branch(:,BR_B);
ysh=1./bs
Is that correct?
3) Then I calculate the nodal voltages in pu
for f=1:24
Vf(f,1)=results.bus(f,VM)*exp(1j*results.bus(f,VA)*(pi/180));%*mpc.bus(f,10);
end
4) Then the nodal currents in pu
I=Ybus*Vf;
5) Finally, I calculate the P(in pu) through a line jk associated with nodal
currents. For the computation of Preal value, the Sbase=100MVA is used for the
whole network?
Thank you in advance for your support!
Cheers,
Alexandra
Alexandra Kapetanaki
PhD Student
Electrical Energy & Power Systems Group, School of Electrical & Electronic
Engineering
Ferranti Building (B18), The University of Manchester, M13 9PL, United Kingdom
Tel: +44 (0) 161 306 2263; Mobile: +44 (0) 7857 598179
________________________________
From: [email protected]
[[email protected]] on behalf of Ray Zimmerman
[[email protected]]
Sent: 23 January 2014 16:58
To: MATPOWER discussion forum
Subject: Re: error message
If you have a working dispatchable load (one that doesn’t give you the error
message you describe) and you are scaling both the active and reactive load
(PMIN and QMIN/QMAX) by multiplying by the same constant factor, you should not
see this error. If that is what you are doing and you are seeing an error,
please send me (off-list) a short script (the smallest example you can come up
with) that I can use to reproduce the error.
--
Ray Zimmerman
Senior Research Associate
B30 Warren Hall, Cornell University, Ithaca, NY 14853
phone: (607) 255-9645
On Jan 20, 2014, at 7:47 AM, Alexandra Kapetanaki
<[email protected]<mailto:[email protected]>>
wrote:
Dear Ray,
In addittion to my previous question, I would like to ask about the following
error message:
Error using makeAvl (line 83) makeAvl: For a dispatchable load, PG and QG must
be consistent with the power factor defined by PMIN and the Q limits.
I face this problem when I iteratively reduce the Load (both MW and MVAr) by
the same constant factor each time.
I use dispatchable loads.
How should I sort this out??
Kind Regards,
Alexandra
Alexandra Kapetanaki
PhD Student
Electrical Energy & Power Systems Group, School of Electrical & Electronic
Engineering
Ferranti Building (B18), The University of Manchester, M13 9PL, United Kingdom
Tel: +44 (0) 161 306 2263; Mobile: +44 (0) 7857 598179
