Ray/Simon, Thank you for the information. Setting generator costs to the values suggested by Prof. Ray did yield the expected results.
Best regards, Guilherme Lira On Tue, Mar 22, 2011 at 6:02 AM, Simon Schneider <[email protected]> wrote: > Hey, > > I惴 not sure if it愀 possible for an OPF to do so, because I think the nearer > you get a value to its constraint, the more it becomes "penalized". > It gets weighted with a factor mu (see mpc.gen(n , 22:25 )?), so the > objective function does not obtain the best solution with the power of one > generator near its maximum. > > Also you have to consider the other constraints, like nodal voltage. The > calculation trys to minimize the objective funtion and find the ideal > balance between all constraints. > At least that愀 what I think it does. I惴 not into the opf mechanisms very > deep yet. > > Greetings > Am 3/21/2011 1:13 PM, schrieb Guilherme Lira: >> >> Simon, >> >> Thanks for the input. >> >> Yes, Pmax for the generator at bus 1 is 35 MW, which is 15 MW short of >> being able to supply the load alone, but (leaving both online) in this >> substation emulation it is desirable to fully use its capacity as its >> connection to the load has the lowest impedance. I'm thinking that, >> even though they are being modeled as substation busbars, the >> generators' operating points might be limited by their capability >> curves, is that correct? >> >> Regards, >> Guilherme Lira >> >> On Mon, Mar 21, 2011 at 6:36 AM, Simon Schneider<[email protected]> >> wrote: >>> >>> Hi Guilherme, >>> >>> if you turn off the second gen (mpc.gen(2,8) = -1) you see, that several >>> other constraints are violated and the opf doesn愒 converge. >>> The Generator at 1 isn愒 powerfull enough to satisfy the load alone. >>> >>> Greetings >>> Simon >>> Am 3/20/2011 10:33 PM, schrieb Guilherme Lira: >>>> >>>> Ray/others, >>>> >>>> In order to test the power loss minimization, I have tried modeling >>>> the generators with equal linear costs simulating substation busbars. >>>> >>>> Please have a look at the attached m-file, it contains a simple test >>>> case consisting of two generators connected to a load, with different >>>> branch impedance values. Theoretically, minimizing losses would mean >>>> that the generator (substation busbar) connected to the load through >>>> the branch of lowest impedance would be serving the load at full power >>>> (Pmax), right? Can you please explain why it is not? >>>> >>>> Thanks, >>>> Guilherme >>> > >
