Try setting Pmax, Pmin, Qmax, Qmin in the case file directly. On May 20, 2013, at 11:12 AM, spyros gian wrote:
> Dear Shri, > Exactly. > I am taking the solution (Pgeneration and Qgeneration for each generator) > from another optimisation tool. > Then I want to make matpower take these values and produce the remaining > results ie voltages etc. > So I want to tell matpower ' only use the values for Pg and Qg that I give > you, so that i see whether you converge and if yes, > then what solution you give'. > > I then go to the mpc.gen matrix, and - as you say - set Pg=Pmax=Pmin, and > Qg=Qmax=Qmin, for each generator. > I run the OPF, and matpower solves the problem without taking this constraint > into account i.e. giving another Pg and another Qg! > Ie it converges to the same result as the one I had before constraining > matpower. > > So we say the same thing here. Why doesnt it work? > > > From: [email protected] > Subject: Re: Constraining matpower > Date: Mon, 20 May 2013 11:03:37 -0500 > To: [email protected] > > I am not sure if I am understanding you correctly here. What I figured you > were doing was to compare the solution of another optimization tool with > MATPOWER's > OPF. To do this you are taking the generation output (Pg, Qg) from the > optimization tool and using it as "fixed" input for MATPOWER's OPF. Hence I > suggested that you set the > Pmax=Pmin=Pg and Qmax=Qmin=Qg so that Pg and Qg remain fixed in MATPOWER's > OPF solution. > > > Shri > > ***** Note that your assumption of the optimization tool and MATPOWER's > solutions "matching" also implicitly assumes that the optimization tool uses > the same objective function, constraints as used in MATPOWER. > > On May 20, 2013, at 10:31 AM, spyros gian wrote: > > Dear Shri, > > I am running an ACOPF not a simple power flow. When I set in the mpc.gen > matrix that > Pg= Pmax=Pmin and Qg=Qman=Qmin (ie the corresponding columns having the same > value) > and then runopf ('caseExample') then , matpower ignores this constraint, ie > that pmax=pmin=pg. > Are you sure it works for you? > Yes, for MATPOWER's case9 system, I constrained Pg and Qg for generators 2 > and 3 to fixed values by setting Pmax=Pmin=Pg and > Qmax=Qmin=Qg and this is what runopf() produces. I don't know why, and its > strange that, the constraints are being ignored in your case. > Perhaps you are not setting something correctly? or the solution has not > converged? > > > MATPOWER Version 4.1, 14-Dec-2011 -- AC Optimal Power Flow > MATLAB Interior Point Solver -- MIPS, Version 1.0, 07-Feb-2011 > Converged! > > Converged in 0.07 seconds > Objective Function Value = 5334.26 $/hr > ================================================================================ > | System Summary > | > ================================================================================ > > How many? How much? P (MW) Q (MVAr) > --------------------- ------------------- ------------- ----------------- > Buses 9 Total Gen Capacity 490.0 -320.3 to 279.7 > Generators 3 On-line Capacity 490.0 -320.3 to 279.7 > Committed Gens 3 Generation (actual) 318.7 -6.8 > Loads 3 Load 315.0 115.0 > Fixed 3 Fixed 315.0 115.0 > Dispatchable 0 Dispatchable -0.0 of -0.0 -0.0 > Shunts 0 Shunt (inj) -0.0 0.0 > Branches 9 Losses (I^2 * Z) 3.69 39.16 > Transformers 0 Branch Charging (inj) - 160.9 > Inter-ties 0 Total Inter-tie Flow 0.0 0.0 > Areas 1 > > Minimum Maximum > ------------------------- -------------------------------- > Voltage Magnitude 1.070 p.u. @ bus 9 1.100 p.u. @ bus 8 > Voltage Angle -3.98 deg @ bus 9 6.66 deg @ bus 2 > P Losses (I^2*R) - 1.73 MW @ line 8-9 > Q Losses (I^2*X) - 11.67 MVAr @ line 8-2 > Lambda P 21.53 $/MWh @ bus 8 22.51 $/MWh @ bus 5 > Lambda Q -0.02 $/MWh @ bus 2 0.10 $/MWh @ bus 9 > > ================================================================================ > | Bus Data > | > ================================================================================ > Bus Voltage Generation Load > Lambda($/MVA-hr) > # Mag(pu) Ang(deg) P (MW) Q (MVAr) P (MW) Q (MVAr) P Q > > ----- ------- -------- -------- -------- -------- -------- ------- > ------- > 1 1.100 0.000* 78.69 13.54 - - 22.311 - > 2 1.098 6.662 150.00 1.93 - - 21.536 > -0.018 > 3 1.087 3.825 90.00 -22.25 - - 21.630 > 0.011 > 4 1.093 -2.161 - - - - 22.311 > 0.001 > 5 1.084 -3.545 - - 90.00 30.00 22.510 > 0.028 > 6 1.100 1.296 - - - - 21.631 > 0.011 > 7 1.089 -0.147 - - 100.00 35.00 21.755 > 0.026 > 8 1.100 2.209 - - - - 21.533 > -0.018 > 9 1.070 -3.976 - - 125.00 50.00 22.499 > 0.095 > -------- -------- -------- -------- > Total: 318.69 -6.78 315.00 115.00 > > ================================================================================ > | Branch Data > | > ================================================================================ > Brnch From To From Bus Injection To Bus Injection Loss (I^2 * Z) > > # Bus Bus P (MW) Q (MVAr) P (MW) Q (MVAr) P (MW) Q > (MVAr) > ----- ----- ----- -------- -------- -------- -------- -------- > -------- > 1 1 4 78.69 13.54 -78.69 -10.50 0.000 3.04 > 2 4 5 32.20 -3.57 -32.05 -14.33 0.152 0.82 > 3 5 6 -57.95 -15.67 59.08 -22.10 1.125 4.90 > 4 3 6 90.00 -22.25 -90.00 26.51 0.000 4.26 > 5 6 7 30.92 -4.41 -30.82 -19.78 0.101 0.85 > 6 7 8 -69.18 -15.22 69.53 0.29 0.346 2.93 > 7 8 2 -150.00 9.74 150.00 1.93 0.000 11.67 > 8 8 9 80.47 -10.03 -78.74 -17.30 1.732 8.71 > 9 9 4 -46.26 -32.70 46.49 14.07 0.231 1.97 > -------- > -------- > Total: 3.687 39.16 > > ================================================================================ > | Voltage Constraints > | > ================================================================================ > Bus # Vmin mu Vmin |V| Vmax Vmax mu > ----- -------- ----- ----- ----- -------- > 1 - 0.900 1.100 1.100 0.977 > 6 - 0.900 1.100 1.100 44.627 > 8 - 0.900 1.100 1.100 113.932 > > ================================================================================ > | Generation Constraints > | > ================================================================================ > Gen Bus Active Power Limits > # # Pmin mu Pmin Pg Pmax Pmax mu > ---- ----- ------- -------- -------- -------- ------- > 2 2 5.164 150.00 150.00 150.00 0.000 > 3 3 1.420 90.00 90.00 90.00 0.000 > > Gen Bus Reactive Power Limits > # # Qmin mu Qmin Qg Qmax Qmax mu > --- --- ------- -------- -------- -------- ------- > 2 2 0.018 1.93 1.93 1.93 0.000 > 3 3 0.000 -22.25 -22.25 -22.25 0.011 > > > IS there a way for this Dr Zimmerman? > > Thank you > > Subject: Re: Constraining matpower > From: [email protected] > Date: Mon, 20 May 2013 08:47:09 -0500 > To: [email protected] > > Setting Pgmax=Pgmin=Pg (similarly for Qg) should constrain the generator > output to a fixed value. > > Shri > > On May 20, 2013, at 8:01 AM, spyros gian <[email protected]> wrote: > > Dear Dr Zimmerman, > > I have solved an ACOPF in an optimisation tool. > I would like to get the solutions from this tool, and plug them to the > matpower. > In particular, I want to get the solutions for the Pgeneration and > Qgeneration for each generator that the optimisation tool gave me, > and plug them into matpower. > > This will allow me to see whether the matpower gives the same values for > voltage magnitudes that I got. > > Should I program some code in matlab so that i constrain matpower's mpc.gen > matrix to have these values? > > I guess that if i put these values to the columns Pg,Qg of the matpower > mpc.gen matrix, this will not constrain matpower. > > > Thank you for your insight > > Syros Giannakos
