Hi Mirish,
There is no way to see the load or renewable curtailment until you get a
converging OPF. It is possible that you will also have to redispatch the
conventional generators in order to get a feasible solution. I would suggest
that you combine your option #2 with curtailable loads, relax the active power
dispatch constraints on the conventional generators (to their normal limits)
and assign piecewise linear costs to those generators with negative or zero
marginal cost up to Pg and large positive marginal cost above Pg. This will
attempt to minimize deviations from the original dispatch pattern, hopefully
moving only those generators necessary to relieve the line overloads.
Ray
> On Nov 29, 2015, at 7:31 PM, Mirish Thakur <[email protected]> wrote:
>
> Hello friends,
>
>
>
> I’m working on (1000 bus system) reactive power dispatch problem. I have
> modeled grid into matpower case file and I’m getting the results of runpf.
> But when I use ACOPF it fails to converge.
> I have modeled grid into two methods
> 1) I used all renewable energy sources generation, pump storage power plant
> and cross border energy transfer as negative load. And all conventional power
> plants as generators. Dispatch of conventional generators is equal to
> residual load so demand is equal to generation. Further I have increased
> limits of slack generator to supply system losses and kept rest of generators
> dispatch constant by Pmax=Pmin=Pg. Also RATE_A limits should be unchanged.
> (Necessary condition for project).
>
> 2) In other way all renewable energy sources generation, pump storage power
> plant and cross border energy transfer are modeled as generators and put next
> to all conventional power plants. And in gencost matrix I used zero variable
> cost for renewable generation. Slack generator and rest of the conditions are
> set as it is in first approach.
>
>
>
> My question is in both modeling I got runpf successfully converged but I’m
> not getting convergence for ACOPF. So, I checked branch limits on some
> branches which I found overloaded by analyzing results of res= runpf
> (mymodel). To avoid such overloading I want to change distribution pattern
> of load which might be cause of overloading of branches. I tried load2disp
> function to get curtailment on load but every time I got failure in
> convergence in runopf. I went through below mentioned discussions-
>
> https://www.mail-archive.com/matpower-l%40cornell.edu/msg04423.html
> <https://www.mail-archive.com/matpower-l%40cornell.edu/msg04423.html>
> https://www.mail-archive.com/matpower-l%40cornell.edu/msg00790.html
> <https://www.mail-archive.com/matpower-l%40cornell.edu/msg00790.html>
> https://www.mail-archive.com/matpower-l%40cornell.edu/msg01203.html
> <https://www.mail-archive.com/matpower-l%40cornell.edu/msg01203.html>
> Is there any way to see curtailment on load or negative generation (renewable
> generation/ cross border transfer of energy) so that I can redistribute that
> load /negative generation on other bus bars so that I can avoid overloading
> of branches and get successful convergence? Many thanks.
> Regards
> Mirish Thakur
>
> KIT University
