Dear Sarmad, Thank you very much! The caveats pointed by you are really helpful. Thanks!
Kind regards, Jin 2018-04-13 13:16 GMT+10:00 Sarmad Hanif <[email protected]>: > Dear Jin, > > Yes, you are right. > > > > However according to my experience, you have to be careful regarding the > calculation of Jacobian of voltage sensitivities which might be required to > translate Lagrange multipliers to LMP components. > > Matpower can give these sensitivities (Jacobian) from the function > makeJac(). > > So if you calculate Jacobian like makeJac(mpc), then it will give you > sensitivity at the base case. > > Hence to get the updated Jacobian (representing the operating conditions), > you need to implement something like makeJac(results_pf), where results_pf > = runpf(mpc). > > Another issue, which I believe was corrected by Ray, was that if you have > generators in the grid they were taken by-default as PV while making the > Jacobian. So you might need to get the updated version of MATPOWER. > > Maybe Ray could shed some more light on making sure the steps for > correctly translating Lagrange multipliers to LMP components. > > > > Hope it helps. > > Best, > > Sarmad > > *From:* [email protected] [mailto: > [email protected]] *On Behalf Of *Ma Jin > *Sent:* Wednesday, 11 April, 2018 5:24 PM > *To:* MATPOWER discussion forum > *Subject:* Re: Question about shadow price of line flow constraints in AC > OPF > > > > Dear Sarmad, > > > > Thanks! Matpower provides the values of all Kuhn-tucker multipliers and > Lagrange multipliers. So it is really a powerful tool which makes > decomposition of the price possible if one wants to. > > > > Kind regards, > > Jin > > > > 2018-04-11 17:12 GMT+10:00 Sarmad Hanif <[email protected]>: > > Hi Jin, > > I couldn’t understand the issue you reported. But according to my > knowledge, MATPOWER gives you the final price at the node, it doesn’t > calculate individual congestion, loss, energy components. > > Moreover, for ACOPF, MATPOWER gives you and active ($/MW) and reactive > power ($/MVar) marginal prices at respective nodes. > > Hope it helps. > > > > *From:* [email protected] [mailto: > [email protected]] *On Behalf Of *Ma Jin > *Sent:* Wednesday, 11 April, 2018 8:04 AM > *To:* [email protected] > *Subject:* Question about shadow price of line flow constraints in AC OPF > > > > Dear all, > > > > I feel confused about the unit of the shadow price of the line flow > constraints in AC based OPF. Since the square of the apparent power is used > when building the line flow constraints, the shadow price should be with a > unit of $/(MVA*MVA). When it is converted to the shadow price $/MVA, > MatPower times the RateA of that line, but for me, it more makes sense if > it is multiplied with the apparent power flowing through the line. What is > the reason behind multiplying that RateA. Thanks! > > > > Kind regards, > > Jin > > >
