Dear MATPOWER community, I have an initial power flow solution for an mpc case file obtained via runpf().
If I then invoke runopf() with quadratic or linear cost on power generation the solver exits without a solution. This is very strange because there exists a feasible solution which I compute with runpf(), and with which I start runopf(). I have considerably relaxed the bounds on PMAX, PMIN, QMAX, QMIN, VMAX, VMIN on all entries of mpc.bus and mpc.gen. I have tried FMINCON and MIPS. Some more information: this phenomenon occurs for the grids from the Simbench project: https://simbench.de/en/ (at least, I tried it for 5 different grids and they all gave the same result). The original data is in csv, but available in pandapower via the simbench package. The OPFs also do not converge in pandapower. I exported the pandapower instances to Matpower mpc cases to test in Matlab. Any help would be greatly appreciated. Please see details of the error messages below. Regards, Willem My errors in Matlab: The grid has 1 generator and 102 loads. The initial feasible point for the generator is: Bus Voltage Generation Load # Mag(pu) Ang(deg) P (MW) Q (MVAr) P (MW) Q (MVAr) ----- ------- -------- -------- -------- -------- -------- 1 1.025 0.000* -31.63 12.20 - - If I use the MIPS solver I get: Warning: Matrix is close to singular or badly scaled. Results may be inaccurate. RCOND = 1.960342e-29. Numerically Failed Did not converge in 16 iterations. >>>>> Did NOT converge (0.56 seconds) <<<<< If I use FMINCON I get: MATPOWER Version 7.1, 08-Oct-2020 -- AC Optimal Power Flow AC OPF formulation: polar voltages, power balance eqns Converged to an infeasible point. fmincon stopped because the size of the current step is less than the value of the step size tolerance but constraints are not satisfied to within the value of the constraint tolerance. <stopping criteria details> >>>>> Did NOT converge (2.25 seconds) <<<<< mpc.gen for this infeasible point returned by FMINCON reads: 1.0000 -28.7893 21.6434 300.0000 -300.0000 0.5739 1.0000 1.0000 200.0000 -200.0000 where the entries are: bus Pg Qg Qmax Qmin Vg mBase status Pmax Pmin, in that order.
