You could fix all generators at their current output values and introduce fictitious generator at bus A and a dispatchable load at B, where the value of the load is very high.
I’m sure there are other formulations to solve ATC, but I’m not familiar with the details of any off the top of my head. Maybe you can find some useful information at the TC Calculator website (http://www.pserc.cornell.edu/tcc/). Ray > On Apr 29, 2015, at 10:40 PM, xiwen wang <[email protected]> wrote: > > Hi Ray, > Thanks for the explanation of ATC calculation. > I have few questions though, hope you can help explain. > > Suppose I have a base case OPF solution already, now I want to figure out how > many MW can be transferred from BUS A to BUS B without violating any > constraint limits. A and B are general single buses and not necessary to be > generator, load. How to do it? > > Besides power flow or OPF, is there any other way to solve ATC? such as using > shift factors, maybe? > > why we need the base case at all? > > thanks > xiwen > > > On Thursday, 2 April 2015, 9:53, Ray Zimmerman <[email protected]> wrote: > > > I’ll assume you have a base case power flow (or OPF) solution in a MATPOWER > case struct mpc and want to find the maximum additional power that can be > transferred from area A to area B without violating constraints, where the > areas are defined via two vectors of bus indices (a and b), possibly by using > a = find(mpc.bus(:, BUS_AREA) == A), etc. Then you’ll just modify the case, > something like this … > > % get indices of generators > ga = find(ismember(mpc.gen(:, GEN_BUS), mpc.bus(a, BUS_I))); % area A gens > gb = find(ismember(mpc.gen(:, GEN_BUS), mpc.bus(b, BUS_I))); % area B gens > gother = find(~ismember((1:ng)', [ga; gb])); % remaining gens > > % fix dispatches of all gens outside areas A and B > mpc.gen(gother, PMIN) = mpc.gen(gother, PG); > mpc.gen(gother, PMAX) = mpc.gen(gother, PG); > > % scale down prices in area A by factor of 10 > % scale up prices in area B by factor of 10 > % (important thing is to make everything in A cheaper than > % everything in B to maximize transfer from A to B) > mpc.gencost(ga, :) = modcost(mpc.gencost(ga, :), 0.1); > mpc.gencost(gb, :) = modcost(mpc.gencost(gb, :), 10); > > % re-run the OPF and compute ATC as total decrease in area B dispatch > r = runopf(mpc); > ATC = sum(mpc.gen(gb, PG)) - sum(r.gen(gb, PG)); > > Hope this helps, > > Ray > > >> On Apr 2, 2015, at 12:10 AM, Aruna Dharmala <[email protected] >> <mailto:[email protected]>> wrote: >> >> Respected sir, >> I am doing ATC computation by optimal power flow >> method.. >> By using matpower software i run the load flow >> solution by optimal power flow.by <http://flow.by/> doing load flow i am not >> geting how to take a group of buses as an area and how to interface between >> areas for available transfer capability calculation..? >> >> On Wed, Apr 1, 2015 at 6:34 PM, Ray Zimmerman <[email protected] >> <mailto:[email protected]>> wrote: >> Another possible approach is to use an OPF and shift the prices down for the >> sending group of generators and up for the receiving group. >> >> Ray >> >> >>> On Apr 1, 2015, at 8:02 AM, Abhyankar, Shrirang G. <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> Although Matpower does not have a function for ATC, it has all the required >>> building blocks for doing the calculations You can take a look at the >>> continuation power flow feature in the MatPower manual as a starting point. >>> >>> Shri >>> >>> On Apr 1, 2015, at 5:07 AM, "Aruna Dharmala" <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>>> Respected sir, >>>> can we do available transfer capability calculation >>>> using matpower it is possible..? >>>> if it possible in this software how the >>>> interfacing between two areas of available transfer capability takes place >>>> for group of buses >> >> > > >
