I figured that out. Your method is correct. The reason for my problem might be that this fluctuations might not be enough for changing the angle values.
Thanks again On Fri, May 18, 2012 at 1:44 PM, Hanie Sedghi <[email protected]>wrote: > Thanks for your help > But > If I consider voltage angles at different buses, it still gives me the > same results no matter the load. > I would be so thankful if you could help me with this. > > Best, > Hanie > > > On Fri, May 18, 2012 at 1:04 PM, Carlos E Murillo-Sanchez < > [email protected]> wrote: > >> Oops, that fourth line should be >> >> >> Nominal_QD = mpc.bus(:, QD); >> >> >> >> Carlos E Murillo-Sanchez wrote: >> >>> There is a rather flexible utility in matpower for scaling loads. Type >>> >> help scale_load >>> >>> at the matlab prompt for help on how to use it. Otherwise, if you just >>> want to modify inflexible demand, >>> you could do something like >>> >>> mpc = loadcase('case118'); >>> define_constants; >>> Nominal_PD = mpc.bus(:, PD); >>> Nominal_QD = mpc.bus(:, QG): >>> for factor = 0.8:0.01:1.20 >>> mpc.bus(:, PD) = factor * Nominal_PD; >>> mpc.bus(:, QD) = factor * Nominal_QD; >>> results = runpf(mpc); >>> % now insert code here to do whatever you want to do with the results >>> your code.... >>> more code... >>> end >>> >>> This scales inflexible demand in the system by a factor from 80% of >>> nominal to 120% of nominal in 1% increments and runs a power flow; you >>> could run also an optimal power flow using runopf() instead. The load is >>> scaled maintaining a constant power factor. >>> >>> >>> >>> >>> Hanie Sedghi wrote: >>> >>>> Dear Sir, >>>> >>>> I would like to have different voltage angle values at different times >>>> for a structure. Let's say I want to have the same structure as case9, but >>>> I want to know what are the values at different times. It is like >>>> simulating a grid and taking samples at different times. For that I think I >>>> need different demands. Then I checked the case file and thought I need to >>>> put random Pg's in "gen" matrix. Am I right? Shall I generate random values >>>> in [Pmin,Pmax] interval? >>>> I have another question, in case9, for bus 1, Pg=0 while Pmin=10. Is it >>>> correct? Can Pg be less than Pmin? In that case,what do we mean by Pmin? >>>> >>>> I would truly appreciate your help. >>>> >>>> Best, >>>> Hanie >>>> >>> >>> >>> >>> >> >> >
