Vids,
Implementing your reformulated OPF equations, written in complementarity
form, is non-trivial in MATPOWER as it will require modifying the
variable/equation sizes and muddling with the OPF data structures. Note
that you'll also need additional equations, perhaps expressed in
semi-smooth form, relating your upward/downward balancing service to
generator power deviation. You will have to spend some time to understand
the OPF data structures and how they are used in the various OPF routines.
One other possible way (that I think will work) is by using the real power
generator deviation \Delta{Pg} as the control variable instead of Pg (see
the attached equations). This will keep the sizes of the
variables/equations for the reformulated OPF same as the original one.
However, you will have to modify the cost function, gradient, Hessian, and
the generator real power limits accordingly.
Shri
-----Original Message-----
From: vids <[email protected]>
Reply-To: MATPOWER discussion forum <[email protected]>
Date: Wed, 27 Aug 2014 16:18:14 +0800
To: <[email protected]>
Subject: Modifying the Power Balance Equations
>Hi Dr Zimmerman and Matpower Community,
>
>I am trying implement an OPF where the real power dispatch is
>pre-determined (as in the case of an energy market where the Q
>schedules are managed separately by the transmission operator).
>
>Is it possible to implement it in Matpower? My idea is to add "slack"
>variables in the nodal energy equations
>
>Pgi - ΔPgi + Pb1i - Pb2i - Pdi = ΣViVjYij(cos(θij + δi -δj)
>
>Pgi - fixed/predetermined real power generated at node i
>ΔPgi - real power 're-scheduling' due to the reactive power dispatch
>Pb1i - upward balancing service at node i
>Pb2i - downward balancing service at node i
>
>Pb1i and Pb2 will have non-zero values when ΔPgi is nonzero, prompting
>other generators to compensate the real power 're-scheduling' when
>needed.
>
>This is the formulation in the dissertation of Dr. El-Samahy, and I
>am wondering if this can be implemented in matpower.
>
>Any ideas would greatly be appreciated. Thank you very much.
>
>--
>2 Cor 12:9
>Each time he said, "My grace is all you need. My power works best in
>weakness." So now I am glad to boast about my weakness, so that the
>power of Christ can work through me.
>
>
