That’s correct. Except, if you are zeroing out all other costs, there is no need to use such a huge magnitude for the cost. Any reasonable non-zero number would do (like 10 or 100). When the problem includes coefficients with huge ranges it can potentially result in numerical issues.
Ray On Oct 12, 2023, at 6:26 PM, Ronald Cabaoig <[email protected]> wrote: Hi sir, Thanks for the suggestion! Let me confirm my understanding: 1. Create a dummy generator with the following limits: -99999 MW <= Pdummy <= 99999 MW 2. To minimize the injection, set a very large positive cost coefficient (C = 99999Pdummy) and zero out all other costs, turning the objective function to: min (99999Pdummy + 0Pg1 + 0Pg2 + ...) 3. To maximize the injection, set a very large negative cost coefficient (C = -99999Pdummy) and zero out all other costs, turning the objective function to: min (-99999Pdummy + 0Pg1 + 0Pg2 + ...) 4. Retain all other information Thanks in advance! Cheers, Ronald On Tue, Oct 10, 2023 at 5:23 AM Ray Daniel Zimmerman <[email protected]<mailto:[email protected]>> wrote: You can do this by placing a dummy generator at the bus of interest and using a very large negative (to maximize the injection) or positive (to minimize the injection) generation cost. You can either zero out all other costs, or simply make the magnitude of the cost large enough to dominate all other costs. Ray > On Oct 5, 2023, at 8:48 PM, Ronald Cabaoig > <[email protected]<mailto:[email protected]>> wrote: > > Dear MATPOWER team, > > Greetings! > > In the current MATPOWER version, is it possible to reformulate the objective > function to find the maximum positive (and negative) power injection in a > certain bus: > > Maximize the positive power injection in bus X (or could also be: minimize > the negative power injection in bus X) > Subject to the AC power flow equations, branch flow limits, generator output > limits, voltage limits. > > The main decision variable in this case would be the power injection in bus > X. Other values that could vary are the generator outputs, voltages, and the > like (all subject to the constraints). > > Cheers, > Ronald
