Can you give me an example of the costs you are using for your dispatchable 
loads? Are they all identical? (feel free to send me your case file off-list)

   Ray


> On May 6, 2015, at 1:19 PM, Carlos Cruzat Hermosilla <[email protected]> 
> wrote:
> 
> Hi Ray
> 
> I checked both possible reasons and I still have the same problem. It is 
> weird that even though I increase the load capacity by 20%, 30% and 50% on 
> per unit I still having the same value of dispatchable loading i.e. 1025.5 
> [MW] somehow there is something fixing this value of dispatchable load as a 
> maximum. Additionally I played around with the costs to see their impact in 
> the dispatchable loads and as I mentioned before this value remains the same 
> 1025.5 [MW]. If I decrease my load this value decreases as well, so I believe 
> there is something fixing this value as a maximum dispatchable load 
> regardless the increasing in load.
> 
> I Hope you could understand, sorry for my writing.
> 
> Thanks, 
> Carlos
> 
> 2015-05-06 16:22 GMT+01:00 Ray Zimmerman <[email protected] 
> <mailto:[email protected]>>:
> Ok, so you are seeing some load being curtailed when you expected that none 
> of it would be? I can think of two possible reasons …
> 
> (1) there are network constraints (branch flow limits) that do not allow all 
> of the load to be served, or
> (2) the value of the load does not exceed the cost of the generation required 
> to serve it.
> 
> You can check the first by trying a case with no line constraints 
> (mpc.branch(:, RATE_A) = 0) to see if that eliminates the curtailment. And 
> you can verify the second by double-checking your generator and load “costs” 
> in the gencost matrix. If you are using a very high price for the loads, you 
> should also see a corresponding price at any buses where curtailment is 
> happing.
> 
>    Ray
> 
> 
>> On May 6, 2015, at 11:07 AM, Carlos Cruzat Hermosilla <[email protected] 
>> <mailto:[email protected]>> wrote:
>> 
>> Hi
>> 
>> Well I am not having trouble specifying the loads as dispatchable. However  
>> as can you see from the System Summary just 1025.5 of 2296.2 [MW], which is 
>> the total load is dispatchable, so a few loads are dispatched at values less 
>> than their nominal value.
>> 
>> I hope this could clarify my question.
>> 
>> Thanks
>> Carlos 
>> 
>> 
>> ================================================================================
>> |     System Summary                                                         
>>   |
>> ================================================================================
>> 
>> How many?                How much?              P (MW)            Q (MVAr)
>> ---------------------    -------------------  -------------  
>> -----------------
>> Buses             24     Total Gen Capacity    5107.5        -535.0 to 2664.0
>> Generators        33     On-line Capacity      5107.5        -535.0 to 2664.0
>> Committed Gens    33     Generation (actual)   1036.0            -124.1
>> Loads             17     Load                  1025.5             208.5
>>   Fixed            0       Fixed                  0.0               0.0
>>   Dispatchable    17       Dispatchable        1025.5 of 2296.2   208.5
>> Shunts             1     Shunt (inj)             -0.0            -108.4
>> Branches          38     Losses (I^2 * Z)        10.53             96.82
>> Transformers       5     Branch Charging (inj)     -              537.7
>> Inter-ties        10     Total Inter-tie Flow   602.1             267.0
>> Areas              4
>> 
>> 2015-05-06 15:54 GMT+01:00 Ray Zimmerman <[email protected] 
>> <mailto:[email protected]>>:
>> We will need more information. What do you mean by “one part of the load 
>> becomes dispatchable”? Are you saying that you are having trouble specifying 
>> your loads as dispatchable or that only a few loads are dispatched at values 
>> less than their nominal value? Or that the loads that are curtailed are only 
>> partially curtailed?
>> 
>> We need to know what specifically you expected to see and how your result 
>> differs from that.
>> 
>>    Ray
>> 
>> 
>> > On May 6, 2015, at 10:11 AM, Carlos Cruzat Hermosilla <[email protected] 
>> > <mailto:[email protected]>> wrote:
>> >
>> > Hi All
>> >
>> > I am currently working with dispatchable loads in order to see the impact 
>> > of overloading the lines of the network. However when I run OPF just one 
>> > part of the total load becomes dispatchable which obviously affects my 
>> > results, so Does anybody knows what could be the reason?
>> >
>> > Thanks,
>> > Carlos
>> >
>> > PD: The generation and lines capacities are enough to provide the required 
>> > energy.
>> 
>> 
>> 
>> 
> 
> 

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