Hi dr Zimmerman, I have one question and one observation Question ---> As generators can consume and inject reactive power, does matpower control de voltage in the nodes via reactive power consumption? In order to reduce the voltage at the injection node. Observation --> If I am not wrong you calculate the Line Series Losses using this equation Loss = (Vf - Vt)^2 / (R +jX) I think Ploss SERIES depends more strongly on the line current I^2 than on the voltage variation at the nodes. My understanding is that Ploss SHUNT depends more strongly on the voltage than on the current. I found this equation for Ploss series Ploss,series = [P/V]^2*Rline + [Q/V]^2*Rline So that the voltage does not influence the losses but the injection of P and Q. Am I wrong about this?? I would appreciate your comments..
>>> Ray Zimmerman <[email protected]> 1/31/2012 4:31 >>> I'm not certain exactly what characteristic of the problem results in this issue, but I have seen it often. The primal/dual interior point algorithm solves an A x = b linear system of equations to compute the update step, and in some cases the corresponding A matrix becomes singular or nearly singular. It may be that the problem is too flat or something, I'm not sure. If it solves successfully anyway, just printing these warnings, it's fine, but sometimes the optimization will fail completely. In that case, my only solution is to switch to a different solver. There are probably improvements that can be made to the MIPS algorithm to make it more robust under these circumstances. Any suggestions are appreciated. -- Ray Zimmerman Senior Research Associate 419A Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Jan 31, 2012, at 4:23 AM, Boris Penaloza wrote: Warning: Matrix is singular to working precision. > In mips at 422 In mipsopf_solver at 145 In opf_execute at 106 In opf at 225 In runopf at 96 In pqinput at 53 I am getting this message error as I try to run a simulation. Does anybody know what it means?? thanks...
