sir
actually, i run an ieee14 bus system and i get the nodal prices at the
respective buses.i take the nodal price at 3rd bus as the marginal
benefit,to reduce the load in that system,i write the code as
mpc0=loadcase('case14o');
define_constants;
>> mpc=load2disp(mpc0,'mo',3,30);
and i take this 30 as my curtailable price at which the load has to
curtail.for that i formulate as,
previously i get the nodal price 40$/MWh.for high price the load
has to curtail,so since 30 is a negative cost,i take it as 40+(40-30).
ie.i take them as -40 and -30.so -30 is greater than -40 so load is
curtailed.to represent it in positive values i convert like this
On Tue, Mar 15, 2016 at 8:52 PM, Ray Zimmerman <[email protected]> wrote:
> I’m afraid I don’t understand your description of your view. I am only
> aware of two quantities involved … (1) the marginal benefit or value of the
> load which directly determines the “cost” of the negative generator used to
> model it, and (2) the nodal price computed by the OPF. (1) is an input, (2)
> is an output, and their relative values determine whether or not the load
> will be curtailed.
>
> So, I don’t understand what you mean by the $30 price you are setting.
>
> Ray
>
>
>
> On Mar 14, 2016, at 11:48 AM, Mounika Vanjarapu <
> [email protected]> wrote:
>
> sir
> thanks for reply.But i think this concept in a different view.
>
> i.e i take the marginal benefit cost as the one
> which we get in the power flow.The price which we set is the high price we
> are setting. we are representing them as negative costs.so i take it as for
> example
> the marginal benefit cost is 40$/MWh,the price we are
> setting is 30$/MWh.since 30 is a negative cost,the total cost which
> we we have to impose to the customer is 40+(40-30)=50$/MWh where
> representing as positive cost.
> Therefore the high price on the customer is 50$/MWh during
> peak periods.Is it absolutely wrong view.
>
> On Mon, Mar 14, 2016 at 6:50 PM, Ray Zimmerman <[email protected]> wrote:
>
>> It is working as expected. The load will be curtailed when the price is
>> higher than the value you assign to the load. So if you assign a value of
>> $38, and the price is $40, it will be curtailed. If you assign the value to
>> $45, the load will not be curtailed at a price of $40. Essentially, you are
>> saying … this load should only be curtailed if the price goes above $45, so
>> you would not expect any curtailment at lower prices (like $40).
>>
>> Ray
>>
>>
>> > On Mar 12, 2016, at 5:08 AM, Mounika Vanjarapu <
>> [email protected]> wrote:
>> >
>> > sir
>> > i am using price sensitive loads concept.i select the bus 4th as my
>> dispatchable load.before converting the loads to dispatchable the LMP at
>> the 4th bus is 40.19$/MWh.now i set the curtailble price at 38 as
>> > mpc=loadcase('case14m');
>> > >> mpc0=load2disp(mpc,'m',4,38);
>> > >> runopf(mpc0)
>> >
>> > MATPOWER Version 5.0b1, 01-Jul-2014 -- AC Optimal Power Flow
>> > MATLAB Interior Point Solver -- MIPS, Version 1.0.2, 01-Jul-2014
>> > Converged!
>> >
>> > Converged in 0.10 seconds
>> > Objective Function Value = 6190.15 $/hr
>> >
>> ================================================================================
>> > | System Summary
>> |
>> >
>> ================================================================================
>> >
>> > How many? How much? P (MW) Q
>> (MVAr)
>> > --------------------- ------------------- -------------
>> -----------------
>> > Buses 14 Total Gen Capacity 772.4 -52.0 to
>> 148.0
>> > Generators 5 On-line Capacity 772.4 -52.0 to
>> 148.0
>> > Committed Gens 5 Generation (actual) 220.2 71.2
>> > Loads 11 Load 211.2 77.4
>> > Fixed 10 Fixed 211.2 77.4
>> > Dispatchable 1 Dispatchable 0.0 of 47.8 -0.0
>> > Shunts 1 Shunt (inj) -0.0 20.7
>> > Branches 20 Losses (I^2 * Z) 8.97 38.85
>> > Transformers 3 Branch Charging (inj) - 24.3
>> > Inter-ties 0 Total Inter-tie Flow 0.0 0.0
>> > Areas 1
>> >
>> > Minimum Maximum
>> > -------------------------
>> --------------------------------
>> > Voltage Magnitude 1.011 p.u. @ bus 3 1.060 p.u. @ bus 1
>> > Voltage Angle -13.69 deg @ bus 14 0.00 deg @ bus 1
>> > P Losses (I^2*R) - 2.72 MW @ line 1-2
>> > Q Losses (I^2*X) - 8.30 MVAr @ line 1-2
>> > Lambda P 35.84 $/MWh @ bus 1 40.03 $/MWh @ bus 3
>> > Lambda Q -0.08 $/MWh @ bus 1 0.56 $/MWh @ bus 14
>> >
>> >
>> ================================================================================
>> > | Bus Data
>> |
>> >
>> ================================================================================
>> > Bus Voltage Generation Load
>> Lambda($/MVA-hr)
>> > # Mag(pu) Ang(deg) P (MW) Q (MVAr) P (MW) Q (MVAr) P
>> Q
>> > ----- ------- -------- -------- -------- -------- --------
>> ------- -------
>> > 1 1.060 0.000* 184.04 0.00 - -
>> 35.838 -0.084
>> > 2 1.041 -3.889 34.80 25.44 21.70 12.70
>> 37.398 -
>> > 3 1.011 -10.790 1.33 28.24 94.20 19.00
>> 40.026 -
>> > 4 1.018 -7.626 - - 0.00* -0.00*
>> 38.762 0.161
>> > 5 1.019 -6.692 - - 7.60 1.60
>> 38.380 0.220
>> > 6 1.060 -12.021 0.00 9.97 11.20 7.50
>> 38.386 -
>> > 7 1.048 -10.804 - - - -
>> 38.787 0.133
>> > 8 1.060 -10.804 0.00 7.52 - -
>> 38.787 -
>> > 9 1.045 -12.468 - - 29.50 16.60
>> 38.802 0.202
>> > 10 1.040 -12.680 - - 9.00 5.80
>> 38.950 0.308
>> > 11 1.046 -12.482 - - 3.50 1.80
>> 38.795 0.225
>> > 12 1.045 -12.873 - - 6.10 1.60
>> 39.007 0.207
>> > 13 1.040 -12.934 - - 13.50 5.80
>> 39.200 0.343
>> > 14 1.024 -13.692 - - 14.90 5.00
>> 39.800 0.559
>> > -------- -------- -------- --------
>> > Total: 220.17 71.16 211.20 77.40
>> >
>> >
>> ================================================================================
>> > | 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 2 125.50 -6.03 -122.78 8.50 2.718
>> 8.30
>> > 2 1 5 58.54 6.03 -56.86 -4.39 1.685
>> 6.96
>> > 3 2 3 64.90 1.90 -63.07 1.21 1.834
>> 7.73
>> > 4 2 4 39.83 0.18 -38.98 -1.19 0.853
>> 2.59
>> > 5 2 5 31.15 2.16 -30.63 -4.25 0.518
>> 1.58
>> > 6 3 4 -29.80 8.03 30.43 -7.74 0.632
>> 1.61
>> > 7 4 5 -37.01 9.82 37.19 -9.22 0.189
>> 0.60
>> > 8 4 7 28.90 -2.65 -28.90 4.28 0.000
>> 1.63
>> > 9 4 9 16.65 1.76 -16.65 -0.35 0.000
>> 1.41
>> > 10 5 6 42.69 16.26 -42.69 -11.86 0.000
>> 4.40
>> > 11 6 11 6.48 4.18 -6.43 -4.08 0.050
>> 0.11
>> > 12 6 12 7.69 2.60 -7.62 -2.45 0.072
>> 0.15
>> > 13 6 13 17.31 7.54 -17.10 -7.12 0.210
>> 0.41
>> > 14 7 8 -0.00 -7.43 0.00 7.52 0.000
>> 0.09
>> > 15 7 9 28.90 3.15 -28.90 -2.30 0.000
>> 0.85
>> > 16 9 10 6.09 3.58 -6.08 -3.55 0.015
>> 0.04
>> > 17 9 14 9.96 3.20 -9.83 -2.93 0.127
>> 0.27
>> > 18 10 11 -2.92 -2.25 2.93 2.28 0.010
>> 0.02
>> > 19 12 13 1.52 0.85 -1.51 -0.85 0.006
>> 0.01
>> > 20 13 14 5.12 2.17 -5.07 -2.07 0.049
>> 0.10
>> > --------
>> --------
>> > Total: 8.968
>> 38.85
>> >
>> >
>> ================================================================================
>> > | Voltage Constraints
>> |
>> >
>> ================================================================================
>> > Bus # Vmin mu Vmin |V| Vmax Vmax mu
>> > ----- -------- ----- ----- ----- --------
>> > 1 - 0.940 1.060 1.060 518.860
>> > 6 - 0.940 1.060 1.060 72.456
>> > 8 - 0.940 1.060 1.060 79.294
>> >
>> >
>> ================================================================================
>> > | Generation Constraints
>> |
>> >
>> ================================================================================
>> > Gen Bus Active Power Limits
>> > # # Pmin mu Pmin Pg Pmax Pmax mu
>> > ---- ----- ------- -------- -------- -------- -------
>> > 4 6 1.614 0.00 0.00 100.00 -
>> > 5 8 1.213 0.00 0.00 100.00 -
>> >
>> > Gen Bus Reactive Power Limits
>> > # # Qmin mu Qmin Qg Qmax Qmax mu
>> > --- --- ------- -------- -------- -------- -------
>> > 1 1 0.084 0.00 0.00 10.00 -
>> >
>> >
>> ================================================================================
>> > | Dispatchable Load Constraints
>> |
>> >
>> ================================================================================
>> > Gen Bus Active Power Limits
>> > # # Pmin mu Pmin Pg Pmax Pmax mu
>> > --- --- ------- -------- -------- -------- -------
>> > 6 4 - -47.80 -0.00 0.00 0.351
>> >
>> > Gen Bus Reactive Power Limits
>> > # # Qmin mu Qmin Qg Qmax Qmax mu
>> > --- --- ------- -------- -------- -------- -------
>> > 6 4 4.868 0.00 0.00 3.90 -
>> >
>> >
>> >
>> >
>> > my doubt is when i set the price at 45 more than the price 40.19 which
>> i get in normal power flow then the load is not curtailed.
>> > 1.the load should be curtailed for prices more than the marginal
>> cost.but here the load is curtailed for less prices.why and what is the
>> concept behind that.
>>
>>
>>
>>
>
>
