This is what I thought you meant and this is what i did. I went to the file
'caseConstr.m' and set the following:
% bus Pg Qg Qmax Qmin Vg
mBase status Pmax Pmin mpc.gen = [ 1 100 37.832
37.832 37.832 1 100 1 100 100
; 2 30 66.286 66.286 66.286 1 100
1 30 30 ; 3 23.039 0
0 0 1 100 1 23.039
23.039 ; ];
So here,you can see that Pg= Pmax=Pmin and Qg=Qmax=Qmin for each of the 3
generators.
When previously you mentioned that setting Pgmax=Pgmin=Pg (similarly for Qg)
solves the problem, did u mean a different way of setting them ?
From: [email protected]
Subject: Re: Constraining matpower
Date: Mon, 20 May 2013 11:41:24 -0500
To: [email protected]
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'sOPF. 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 thePmax=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
thatPg= 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 andQmax=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 FlowMATLAB Interior Point
Solver -- MIPS, Version 1.0, 07-Feb-2011Converged!
Converged in 0.07 secondsObjective 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 279.7Generators 3 On-line Capacity 490.0
-320.3 to 279.7Committed Gens 3 Generation (actual) 318.7
-6.8Loads 3 Load 315.0 115.0
Fixed 3 Fixed 315.0 115.0
Dispatchable 0 Dispatchable -0.0 of -0.0 -0.0Shunts
0 Shunt (inj) -0.0 0.0Branches
9 Losses (I^2 * Z) 3.69 39.16Transformers 0
Branch Charging (inj) - 160.9Inter-ties 0 Total
Inter-tie Flow 0.0 0.0Areas 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 8-9Q Losses (I^2*X) - 11.67
MVAr @ line 8-2Lambda 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
