To get exactly the same solution you also need to scale any shunt capacitors,
baseMVA and all power limits on gens and lines. The following gives me same
solution as the original (just scaled).
define_constants;
mpc = loadcase('case14');
s = 100;
mpc.baseMVA = mpc.baseMVA / s;
mpc.bus(:, PD:BS) = mpc.bus(:, PD:BS) / s;
mpc.gen(:, [PG:QMIN PMAX:PMIN]) = mpc.gen(:, [PG:QMIN PMAX:PMIN]) / s;
mpc.branch(:, RATE_A) = mpc.branch(:, RATE_A) / s;
mpc.gencost(:, COST) = mpc.gencost(:, COST) * s^2;
mpc.gencost(:, COST+1) = mpc.gencost(:, COST+1) * s;
r = runopf(mpc);
Hope this helps,
--
Ray Zimmerman
Senior Research Associate
419A Warren Hall, Cornell University, Ithaca, NY 14853
phone: (607) 255-9645
On Feb 7, 2012, at 10:01 AM, Keshav Prashad Pokharel wrote:
> Hi,
>
> I am trying to reduce the size of IEEE 14 bus system by 100 in order to
> use/analyse the system to be used with small generating units. Due to the
> smaller size of additional generators I am considering, it will be easy if
> the size of the system can be reduced by 100 (i.e. reducing the size of
> existing generators and loads by 100). I used the following codes, but error
> message comes when I try to run the opf (Matrix is close to singular or badly
> scaled, numerically failed etc..)
>
> mpc = loadcase('case14');
> mpc.gen (:, 2:5) = mpc.gen(:, 2:5) / 100; % dividing PG, QG, QMAX & QMIN by
> 100.
> mpc.gen (:, 9) = mpc.gen (:, 2)/100 + 100; % Reducing the PMAX
> mpc.bus (:, 3:4) = mpc.bus (:, 3:4) / 100; % diving PD & QD by 100
> mpc = ext2int(mpc);
> savecase('case14_new’, mpc);
> runopf ('case14_new’);
>
> I am not sure, whether the size of the system can be reduced by 100 in this
> case.
> Can anybody pls help me in this regard.
>
> Keshav Pokharel
> PhD Student, University of Central Lancashire
> England
