Are you saying that your solution includes voltage angles whose absolute value is greater than 0.26 radians or 14.9 degrees?
Ray > On Oct 11, 2017, at 8:52 PM, Viswanath Hariharan <vhari...@buffalo.edu> wrote: > > First, thank you so much for your time, Sir. > So I tried the first approach first. I want to added box constraints for > Voltage angle, -0.26 < theta < 0.26. I created the A matrix and l and u > vectors and passed it to the opf function. The solution converged and I did > get results. But the problem is that the added constraints look like they had > no effect on the result. > > I also tried the toggle_reserves() method you suggested in the previous email > of this thread where you asked me rename toggle_reserves and all the callback > functions within it and modify its contents to toggle the addition of > constraints. I did that too. results = runopf(mpc) and results.om > <http://results.om/> had 5 linear constraints added to it. But again this had > no effect on the results. I even tried changing the bounds to see if there > was any difference but there wasn't. > > What is it that I'm missing out here? > > Regards > Viswanath > > > > On Tue, Oct 10, 2017 at 9:09 AM, Ray Zimmerman <r...@cornell.edu > <mailto:r...@cornell.edu>> wrote: > It appears you have fundamentally misunderstood callback functions and how > they work. I suggest that you read carefully the entirety of sections 7.2–7.5 > in the User’s Manual and make sure you understand the toggle_reserves() > example used to illustrate the approach. > > To implement your own constraints, I would recommend copying and renaming > toggle_reserves() to something like toggle_myconstraints(). Then rename all > of the callback functions defined in that file to e.g. > userfcn_myconstraints_ext2int(), userfcn_myconstraints_formulation(), etc., > and modify their contents to reflect the constraints you want to add (as > opposed to those implemented for the zonal reserves case). The “formulation” > callback is where you’ll be calling add_constraints(). Then you can simply > toggle your constraints on and use runopf() normally. > > mpc = loadcase('<mycase>'); > mpc = toggle_myconstraints(mpc, 'on'); > results = runopf(mpc); > > Hope this helps, > > Ray > > > >> On Oct 5, 2017, at 12:18 PM, Viswanath Hariharan <vhari...@buffalo.edu >> <mailto:vhari...@buffalo.edu>> wrote: >> >> Sir >> >> I tried adding constraints using the callback functions method described in >> Section 7.2 but I am not sure I followed it correctly. >> mpopt = mpoption; >> om = opf_setup(mpc, mpopt); >> om = add_constraints(om, 'Vm', A1, l1, u1); >> om = add_constraints(om, 'Va', A2, l2, u2); >> mpc = get_mpc(om) >> results2 = runopf(mpc); >> >> om gets updated with 10 linear constraints (case5 is being used here). But >> mpc doesn't get updated and hence when I run this code and check and >> results.var.mu.l.Va <http://results.var.mu.l.va/>, the constraints aren't >> updated. Not only that, the mpc file isn't getting updated as well. I think >> I am making some mistake with this line : mpc = get_mpc(om) because om is >> fine. What am I missing here? Or should I take another approach? >> Thank you so much for your time Sir. >> >> Regards >> Viswanath Hariharan >> >> On Thu, Oct 5, 2017 at 10:27 AM, Ray Zimmerman <r...@cornell.edu >> <mailto:r...@cornell.edu>> wrote: >> You only need to use the add_constraints() function if you are using >> Callback Functions as described in Section 7.2 as opposed to Direct >> Specification as described in Section 7.1 of the User’s Manual >> <http://www.pserc.cornell.edu/matpower/docs/MATPOWER-manual-6.0.pdf>. >> >> You convergence failure my just imply that your variable bounds are tight >> enough that there is no feasible solution. Try relaxing the limits and see >> if it converges. >> >> Vm, Pg and Qg all have limits specified directly in the bus and gen >> matrices. Vm is bounded by the VMIN and VMAX columns in the bus matrix. Pg >> and Qg are bounded by the PMIN, PMAX and QMIN, QMAX columns of the gen >> matrix, respectively. Va is not normally constrained (except at the >> reference bus), so the bus matrix doesn’t contain bounds for it. In that >> case, you have to use the standard linear constraints of equation (6.25) to >> impose bounds. >> >> At a lower lever, variable bounds are defined when variables are added via >> the add_vars() method. The Va, Vm, Pg and Qg variables are added >> automatically (with their bounds) in opf_setup(), so you can’t really modify >> them there. But for any variables you add later, you supply the bounds when >> you call add_vars(). >> >> Ray >> >> >> >>> On Oct 4, 2017, at 3:52 PM, Viswanath Hariharan <vhari...@buffalo.edu >>> <mailto:vhari...@buffalo.edu>> wrote: >>> >>> So I do not need to use the add_constraints function? Because when I used >>> the code you mentioned and then runopf(mpc), convergence fails. In general, >>> how to add box constraints for Va,Vm, Pg and Qg of xr (r = runopf(mpc); >>> r.raw.xr). >>> If I have to use the add_constraints function, how do I do that? >>> >>> Regards >>> Viswanath Hariharan >>> >>> On Wed, Sep 27, 2017 at 1:39 PM, Ray Zimmerman <r...@cornell.edu >>> <mailto:r...@cornell.edu>> wrote: >>> Voltage magnitude constraints are already included. Simply set the VMIN and >>> VMAX columns in the bus matrix to the desired values. >>> >>> For voltage angles, simply define the A, l and u corresponding to equation >>> (6.25) in the User’s Manual >>> <http://www.pserc.cornell.edu/matpower/docs/MATPOWER-manual-6.0.pdf>. >>> Something like the following … >>> >>> mpc = loadcase(<your-case-name>); >>> nb = size(mpc.bus, 1); >>> ng = size(mpc.gen, 1); >>> mpc.A = sparse(1:nb, 1:nb, 1, nb >>> <https://maps.google.com/?q=1:nb,+1,+nb&entry=gmail&source=g>, 2*nb+2*ng); >>> mpc.u = 0.26 * ones(nb, 1); >>> mpc.u = -mpc.l; >>> >>> — Ray >>> >>> >>> >>>> On Sep 23, 2017, at 5:25 PM, Viswanath Hariharan <vhari...@buffalo.edu >>>> <mailto:vhari...@buffalo.edu>> wrote: >>>> >>>> Hello Sir >>>> >>>> I want to add voltage magnitude and voltage angle constraints to the >>>> opf solver but I am not able to figure out how to. >>>> >>>> Voltage magnitude constraints ---> 0.9 <= Vm <= 1.1 >>>> Voltage angle constraints ---> - 0.26 <= Va <= 0.26 (Unrelaxed form) >>>> >>>> I read a post where you mentioned to add these constraints to the case >>>> struct which looked pretty simple in the post but I didn't know how to add >>>> that to the case struct. >>>> I was wondering if you can guide me on how to do it. Hoping to hear from >>>> you soon. >>>> >>>> Regards >>>> Viswanath Hariharan >>>> Graduate Research Assistant >>>> Electrical Engineering >>>> University at Buffalo >>> >>> >> >> > >
