Thank You, Mirish and Shri for the guidance. Shri, the model is converging now. I understand that Vmax and Vmin limits should have been more relaxed. I have a couple of quick follow-up questions:
- I had set the voltage magnitudes on per unit basis since the network voltages range from 69kV to 500kV. By now making Vm=1, wouldn't all voltages be set equal to 500kV? - Also, while relaxing line limits, what is the maximum acceptable percentage I should be increasing those values to? sincerely, Aakanksha *Dubey* On Wed, Mar 7, 2018 at 7:25 PM, Abhyankar, Shrirang G. <[email protected]> wrote: > The voltage magnitudes in MATPOWER data files, (bus(:,VM)), are given in > per unit and are generally close to 1.0. You have very low voltages for > many of the buses. Similarly, the VMAX and VMIN values are also in per unit > and generally they are 1.0 and 0.95, respectively. The following code > results in convergent OPF. > > > > mpc = loadcase(‘Transmission3’); > > define_constants; > > mpc.bus(:,VM) = 1.0; > > mpc.bus(:,VA) = 0.0; > > mpc.bus(:,VMAX) = 1.1; > > mpc.bus(:,VMIN) = 0.9; > > runopf(mpc); > > > > Also, note that when relaxing the limits set them to large values, not > zeros. > > > > Thanks, > > Shri > > Ph: (630) 252 0219 <(630)%20252-0219> > > www.mcs.anl.gov/~abhyshr > > *From: *<[email protected]> on behalf of > Aakanksha Dubey <[email protected]> > *Reply-To: *MATPOWER discussion forum <[email protected]> > *Date: *Wednesday, March 7, 2018 at 4:23 PM > *To: *"[email protected]" <[email protected]> > *Subject: *AC OPF Convergence Issue > > > > Hi All, > > > > I am developing a model for transmission grid at Lehigh Valley. My model > seems to converge for DC OPF but is unable to converge for AC. I have tried > the following to make it converge but nothing works: > > > > · Relaxed Vmax, Vmix, BR_R, Rate_A,Rate_B,Rate_C > > · Checked the tap ratio, Qmax, Qmin,Pmax,Pmin > > · Tried to change the OPF options by using opf.init_from_mpc > > · Using mpoption I tried to change the solver to IPOPT& MINOPF > but MATLAB keeps giving me an error that I need to download it. After > downloading and connecting the path to MATLAB it gives me the same error. > > I have attached my casefiles to this email. Please let me know if anyone > can find an issue with the model. > > > > Thank you! > > > > Aakanksha > > >
