My mean is this:
For the following code the results are always the same. Why I have to get
the same results by changing voltage limits
define_constants;
mpc = loadcase('case9');
for k = 1:5
m=abs((normrnd(1,1,8760,1)));
V = m(1); % generate a random draw of voltages
mpc.bus(1:6, VMIN) = V;
mpc.bus(1:6, VMAX) = V;
r = runopf(mpc);
end
Best Wishes
Silvio Miceli
On Mon, Mar 26, 2012 at 17:25, Ray Zimmerman <[email protected]> wrote:
> Sorry, you are going to have to describe what you are doing in a bit more
> detail and ask your question more clearly. Different results between what
> and what for the OPF? Same results between what and what for runmarket?
> What is the reason for what?
>
> --
> Ray Zimmerman
> Senior Research Associate
> 419A Warren Hall, Cornell University, Ithaca, NY 14853
> phone: (607) 255-9645
>
>
>
>
> On Mar 26, 2012, at 11:20 AM, Silvio Miceli wrote:
>
> Dear Ray,
>
> When I do an OPF with variable voltages I get different results while for
> the runmarket I get the same results. runmarket is done underlying an
> OPF. What is the reason?
>
> Best Wishes
>
> Silvio Miceli
>
>
> On Sun, Mar 25, 2012 at 03:28, Silvio Miceli <[email protected]>wrote:
>
>> Dear Prof. Zimmerman,
>>
>> Thank you very much.
>>
>> Best Wishes
>>
>> Silvio Miceli
>>
>>
>>
>> On Sat, Mar 24, 2012 at 01:44, Ray Zimmerman <[email protected]> wrote:
>>
>>> As I mentioned before, in MATPOWER's OPF the voltages *are* optimization
>>> variables. In other words, they are *output* values that depend on all of
>>> the input parameters. If you want to treat the voltages at generator buses
>>> as inputs (that you can set randomly according to some distribution), then
>>> you will need to set the VMIN and VMAX values at that corresponding bus to
>>> the desired value before calling the OPF.
>>>
>>> Something like this, where randomvoltage() is a function that returns a
>>> voltage for each generator bus drawn from some specified distribution and
>>> ig is the vector of indexes of generator buses ...
>>>
>>> mpc = loadcase('mybasecase');
>>> for k = 1:10000
>>> V = randomvoltage(); % generate a random draw of voltages
>>> mpc.bus(ig, VMIN) = V;
>>> mpc.bus(ig, VMAX) = V;
>>> r = runopf(mpc);
>>> % save whatever outputs you want to collect
>>> end
>>>
>>> --
>>> Ray Zimmerman
>>> Senior Research Associate
>>> 419A Warren Hall, Cornell University, Ithaca, NY 14853
>>> phone: (607) 255-9645
>>>
>>>
>>>
>>>
>>> On Mar 23, 2012, at 7:13 PM, Silvio Miceli wrote:
>>>
>>> Dear Johnny
>>>
>>> I want to do a probabilistic OPF by using Monte Carlo. So, I have to
>>> load a distribution of voltage at the buses. I think MATPOWER is not able
>>> to load variables as optimization variable. If you have an idea please let
>>> me know.
>>>
>>> Best Wishes
>>>
>>> Silvio Miceli
>>>
>>>
>>> On Fri, Mar 23, 2012 at 23:39, Johnny <[email protected]> wrote:
>>>
>>>> Silvio Miceli <[email protected]> writes:
>>>>
>>>> > Dear Shiyang,
>>>> >
>>>> > I also want to do it by Monte Carlo, but not loads. I want to have a
>>>> > distribution of voltage as input. When I load loadcase it gives
>>>> error. My mean
>>>> > is this:
>>>> > I want load variable voltage values in bus matrix. Is it possible?
>>>> >
>>>>
>>>> Silvio,
>>>>
>>>> I believe the best way to achieve this is to generate the normal
>>>> distibution in a script which calls the OPF solver and collect the
>>>> results to display as a distribution. So, in the Monte Carlo, you use
>>>> stochastic input on a Black Box model and collect stochastic
>>>> output. This normally takes some time, but what do you look for really?
>>>>
>>>>
>>>>
>>>> > Best Wishes
>>>> >
>>>> > Silvio Miceli
>>>> >
>>>> > On Fri, Mar 23, 2012 at 23:19, 李诗旸 <[email protected]> wrote:
>>>> >
>>>> > HI Silvio Miceli,
>>>> >
>>>> > I think Mr. Zimmerman’s suggestion is the way like Monte Carlo
>>>> Method.
>>>> > Normally, you may have the distributions of some parameters
>>>> (inputs) such
>>>> > as loads and active generations, then you could use that way to
>>>> get the
>>>> > distributions of the optimized voltages (output) numerically.
>>>> >
>>>> >
>>>> >
>>>> > Sincerely
>>>> >
>>>> > Shiyang Li
>>>> >
>>>> >
>>>> >
>>>> > 发件人: [email protected] [mailto:
>>>> > [email protected]] 代表 Silvio Miceli
>>>> > 发送时间: 2012年3月24日 4:31
>>>> > 收件人: MATPOWER discussion forum; Ray Zimmerman
>>>> > 主题: Re: probabilistic voltage
>>>> >
>>>> >
>>>> >
>>>> > I want to a have a distribution of voltage at buses that it is an
>>>> > optimization variable in MATPOWER? These distributions are the
>>>> inputs for
>>>> > the OPF.
>>>> >
>>>> > Best Wishes
>>>> >
>>>> >
>>>> >
>>>> > Silvio Miceli
>>>> >
>>>> > On Fri, Mar 23, 2012 at 21:25, Ray Zimmerman <[email protected]>
>>>> wrote:
>>>> >
>>>> > I'm afraid I don't know what *you* mean. The voltages are
>>>> *outputs* of
>>>> > MATPOWER's OPF. So what are the input parameters that you would
>>>> like to be
>>>> > stochastic? Voltage limits?
>>>> >
>>>> >
>>>> >
>>>> > --
>>>> >
>>>> > Ray Zimmerman
>>>> >
>>>> > Senior Research Associate
>>>> >
>>>> > 419A Warren Hall, Cornell University, Ithaca, NY 14853
>>>> >
>>>> > phone: (607) 255-9645
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> > On Mar 23, 2012, at 2:40 PM, Silvio Miceli wrote:
>>>> >
>>>> > My problem is this I cannot do loadcase. How can I do many, many
>>>> > deterministic optimization? If I introduce voltage as x and do it
>>>> with a
>>>> > FOR?
>>>> >
>>>> >
>>>> >
>>>> > Could you please explain better? I didn't understand. I am sorry.
>>>> >
>>>> > Best Wishes
>>>> >
>>>> >
>>>> >
>>>> > Silvio Miceli
>>>> >
>>>> > On Fri, Mar 23, 2012 at 19:22, Ray Zimmerman <[email protected]>
>>>> wrote:
>>>> >
>>>> > MATPOWER does not implement any stochastic optimization. All of
>>>> it's
>>>> > variables and parameters are assumed to be deterministic.
>>>> However, one
>>>> > approach to handling probabilistic parameters is to simply do
>>>> many, many
>>>> > deterministic optimizations, where each one involves, for each
>>>> > probabilistic parameter, drawing a value from the corresponding
>>>> > distribution. Such an approach could use MATPOWER's OPF as a
>>>> subroutine to
>>>> > solve the deterministic sub-problem.
>>>> >
>>>> >
>>>> >
>>>> > --
>>>> >
>>>> > Ray Zimmerman
>>>> >
>>>> > Senior Research Associate
>>>> >
>>>> > 419A Warren Hall, Cornell University, Ithaca, NY 14853
>>>> >
>>>> > phone: (607) 255-9645
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> > On Mar 23, 2012, at 12:42 PM, Silvio Miceli wrote:
>>>> >
>>>> > Dear Dr. Zimmerman,
>>>> >
>>>> >
>>>> >
>>>> > I want to have probabilistic voltage or reactive power in an OPF.
>>>> In other
>>>> > words, I want to do OPF with probabilistic variables,e.g. voltage
>>>> should be
>>>> > a normal distribution of voltage. How can insert this kind of
>>>> variables to
>>>> > case file of MATPOWER? Is there this possibility in MATPOWER?
>>>> >
>>>> >
>>>> >
>>>> > Best Wishes
>>>> >
>>>> >
>>>> >
>>>> > Silvio Miceli
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>> >
>>>>
>>>> --
>>>> Johnny
>>>>
>>>>
>>>>
>>>
>>>
>>
>
>
