Reference
Alireza Soroudi, Power System Optimization Modelling in GAMS, Model EDsensitivity (Gcode3.2) in chapter Power Plant Dispatching, 2017
$title Sensitivity Analysis in Economic Load Dispatch

$onText
For more details please refer to Chapter 3 (Gcode3.2), of the following book:
Soroudi, Alireza. Power System Optimization Modeling in GAMS. Springer, 2017.
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Model type: QCP
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Contributed by
Dr. Alireza Soroudi
IEEE Senior Member
Email: alireza.soroudi@gmail.com
We do request that publications derived from the use of the developed GAMS code
explicitly acknowledge that fact by citing
Soroudi, Alireza. Power System Optimization Modeling in GAMS. Springer, 2017.
DOI: doi.org/10.1007/978-3-319-62350-4
$offText

Set
   Gen     / g1*g5  /
   counter / c1*c11 /;

Parameter report(counter,*), repGen(counter,Gen);

Scalar load / 400 /;

Table data(Gen,*)
       a     b      c       Pmin  Pmax
   G1  3     20     100     28    206
   G2  4.05  18.07  98.87   90    284
   G3  4.05  15.55  104.26  68    189
   G4  3.99  19.21  107.21  76    266
   G5  3.88  26.18  95.31   19    53;

Variable P(gen), OF;
Equation eq1, eq2;

eq1.. OF =e= sum(gen, data(gen,'a')*P(gen)*P(gen) + data(gen,'b')*P(gen) + data(gen,'c'));

eq2.. sum(gen, P(gen)) =g= load;

P.lo(gen) = data(gen,'Pmin');
P.up(gen) = data(gen,'Pmax');

Model ECD / eq1, eq2 /;

loop(counter,
   load = sum(gen, data(gen,'Pmin')) + ((ord(counter)-1)/(card(counter)-1))*sum(gen, data(gen,'Pmax') - data(gen,'Pmin'));
   solve ECD using qcp minimizing of;
   repGen(counter,Gen)    = P.l(gen);
   report(counter,'OF')   = of.l;
   report(counter,'load') = load;
);
display repgen, report;