The answer is actually correct based on the value of the load curtailment
assumed by load2disp(), which is $5000. You can simply change that value in the
gencost matrix if you want something smaller.
E.g.
mpc_LC.gencost(3:6, COST) = 100;
Hope this helps,
Ray
> On Dec 10, 2014, at 10:32 PM, difei tang <[email protected]> wrote:
>
> Dear Prof. Zimmerman and Matpower users,
>
> I am doing AC OPF load shedding with generator failure.
> I used load2disp.m to convert all the fixed load to dispatchable load.
> The code is:
> mpc = loadcase('case9');
> mpc_LC = load2disp(mpc);
> mpc_LC.gen(1,8) = 0; % set Gen 1 and 3 out of service
> mpc_LC.gen(3,8) = 0;
> [results_LC, success_LC] = runopf(mpc_LC);
>
>
> Converged in 0.67 seconds
> Objective Function Value = -1210215.60 $/hr
> ================================================================================
> | Bus Data
> |
> ================================================================================
> Bus Voltage Generation Load
> Lambda($/MVA-hr)
> # Mag(pu) Ang(deg) P (MW) Q (MVAr) P (MW) Q (MVAr) P Q
>
> ----- ------- -------- -------- -------- -------- -------- -------
> -------
> 1 1.028 0.000* - - - -
> 5068.403-204.208
> 2 1.033 18.804 249.33 18.30 - - 43.586 -
> 3 1.049 2.700 - - - -
> 4942.836-205.941
> 4 1.028 0.000 - - - -
> 5068.403-204.208
> 5 1.034 -0.714 - - 50.35* 16.78*
> 5072.673-218.018
> 6 1.049 2.700 - - - -
> 4942.836-205.941
> 7 1.025 4.947 - - 100.00* 35.00*
> 4904.162-170.803
> 8 1.033 10.406 - - - -
> 4818.644-159.149
> 9 1.007 0.746 - - 92.93* 37.17*
> 5071.383-178.457
> -------- -------- -------- --------
> Total: 249.33 18.30 243.28 88.96
>
> The total cost and nodal price results are very high.Which is obviously wrong.
> The total cost is a big negative value because of the high cost of negative
> generator (5000 set by load2disp.m).
>
> My question is:
> 1. How can I achieve the load shedding without the big value of total cost
> and nodal price?
> 2. I would like to add a load curtailment cost for the load which is shed.
> How can I do this? Do I need to add user cost functions?
>
