Dear Matpower community, I was doing some interpretation for pattern of Lagrange multiplier correspond to Qg limits on case5.m.
I have done some modification on the network which are as follows: m = loadcase(case5); m.bus(:,[3,4]) = m.bus(:,[3,4])*0.65; m.bus(:,[4]) = m.bus(:,[4])*-2; r = runopf(m); With the above modification, I get the following result for reactive power limit of generator at bus 4. Gen Bus Reactive Power Limits # # Qmin mu Qmin Qg Qmax Qmax mu ---- ----- ------- -------- -------- -------- ------- 4 4 0.001 -150.00 -145.20 150.00 - >From the above result, Qg(=-145.20) is still within its limits [-150,150]. My understanding of Lagrange multiplier is that it remains zero for the inequality constraint that is < or > 0. Its value will be non-zero only if the inequality constraint is = 0. Although, the Qmin mu(=0.001) is small, however, Qg is 4.8 off from its lower bound. Am I missing some obvious link here? Thank you in advance. Best regards, Deep Kiran Research Scholar, IIT Delhi, India
