Thankyou for the help, mister Ray, i did what you told me and the OPF converged, i put generators in every bus and had to modify my voltage constraints from Vmax=1.05 and Vmin=0.95 to Vmax=1.1 and Vmin=0.9, and also some branch flow constraints, but i think i can solve that by checking the loads...
Now, i wanna modify the OPF's objective function to minimize the power losses in the branches, and the reactive power compensation (the reactive power injected by the generators that i added), ¿how can i access the objective function to make the modifications? ________________________________ De: [email protected] <[email protected]> en nombre de Ray Zimmerman <[email protected]> Enviado: martes, 08 de noviembre de 2016 02:43 p.m. Para: MATPOWER discussion forum Asunto: Re: Optimal reactive compensation in MATPOWER If you have a power flow solution, you could relax the generator, voltage and branch flow limits to include the power flow solution. Then gradually begin to tighten the constraints by moving the limits gradually toward their original values and resolving the OPF. This way you may be able to discover which constraints are in conflict with one another. Ray On Nov 8, 2016, at 11:05 AM, Angel Pastor <[email protected]<mailto:[email protected]>> wrote: And ¿is there a way to "make" the OPF converge?... Which would be the main reasons why an OPF does not converge? ________________________________ De: [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> en nombre de Ray Zimmerman <[email protected]<mailto:[email protected]>> Enviado: martes, 08 de noviembre de 2016 11:45 a.m. Para: MATPOWER discussion forum Asunto: Re: Optimal reactive compensation in MATPOWER I’m afraid I cannot speculate on the reasons for non-convergence of the OPF in your case. There are numerous ways in which an OPF problem can end up with an empty feasible region. Ray On Nov 8, 2016, at 12:07 AM, Angel Pastor <[email protected]<mailto:[email protected]>> wrote: Thank's for your answer mister Zimmerman, i tried with some of the cases in the Matpower files like the case30 and case14 and it worked. But in the system i'm working the OPF does not converge and it says it numerically fails, when i run the normal power flow it converges but it doesn't satisfy neither the voltage or the generation constraints, ¿that could be the reasson why the OPF does not converge? I was trying to apply an optimal reactive compensation to solve that problem and get the OPF satisfying all the constraints. ________________________________ De: [email protected]<mailto:[email protected]> <[email protected]<mailto:[email protected]>> en nombre de Ray Zimmerman <[email protected]<mailto:[email protected]>> Enviado: lunes, 07 de noviembre de 2016 11:06 a.m. Para: MATPOWER discussion forum Asunto: Re: Optimal reactive compensation in MATPOWER You could add a generator at each bus and then use an OPF to solve for the power flows, with the real power dispatches constrained to their initial values. Ray On Nov 6, 2016, at 9:40 AM, Angel Pastor <[email protected]<mailto:[email protected]>> wrote: Dear MATPOWER community. Hi to everyone, i'm trying to implement reactive power compensation in a power system, my goal is to make voltage in all buses have values within the constraints, but i don't know neither the ubication for the compensation or the MVAR's that would give me the optimal solution and satisfy all the constraints. So i was wondering if there is a way for matpower to get me that information. My system consist in 14 buses, 5 PV (one generator per bus) and 9 PQ. I was thinking in modeling the compensators as reactive power generators with no Pg, as in a OPF the reactive power generated Qg is an optimization variable, but i only have that variable in the PV buses, and i need to be able to compensate in any bus to have the optimal solution. I could make all the buses PV to put generator in all the buses, but then the voltage would be attached to de Vg values from the gen_matrix. Other idea i had was to add a new variable with the add_userfcn. function and change the OPF formulation with function om = userfcn_reserves_formulation(om, args) But i think that variable would still be limitated to to the PV buses and would only add a reserve to the current generators. If you could help me with this, i would really appreciate it. Hoping to get response. Thanks in advance. Angel Araque, Electrical Engineering student in University of Los Andes. Venezuela
