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 =
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.
[mailto:bounce-122459850-74036...@list.cornell.edu] 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
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.
2018-04-11 17:12 GMT+10:00 Sarmad Hanif
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.
On Behalf Of Ma Jin
Sent: Wednesday, 11 April, 2018 8:04 AM
Subject: Question about shadow price of line flow constraints in AC OPF
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!