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 >> >> >> > > >
