Again, as with non-marginal generators, this will not give you the LMP unless the load is a dispatchable load that is marginal (partially dispatched). If the load is a fixed load it's utility is infinite and it won't help you find the LMP, which is the sensitivity of the OPF objective function to an incremental increase in load at the bus.
-- Ray Zimmerman Senior Research Associate 419A Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Mar 5, 2013, at 11:14 PM, Kartik Pandya <[email protected]> wrote: > For finding the LMPs of remaining load buses, you require utility function of > the load buses. values of some utility functions are given in the following > paper. > H Liu et al., "Social welfare maximization in transmission enhancement > considering network congestion", IEEE trans. on power systems, vol. 23, no. > 3, August 2008, pp. 1105-1114. Please refer table no. VII on page no. 1113. > > From: Khirad Dhabhar <[email protected]> > To: MATPOWER discussion forum <[email protected]> > Sent: Monday, 4 March 2013 4:05 PM > Subject: Re: performing lmp calculation > > Mr Karthik. > > Let me take the 30 bus case as an example. Thus their are 6 gen and hence 6 > cost functions.Thus when i take the partial differential i will get six > equations. Thus the LMP values of the generator bus. I want the LMP values of > all the 30 buses. How do we get that. > > Thanks > khirad > > > On 2 March 2013 11:24, Kartik Pandya <[email protected]> wrote: > If your problem size is small then you should get same opf results with ABC > method and MINOS (MATPOWER) solver. but for large scale problem, > to get LMP with ABC, first run opf with ABC to get Pg of all generators. then > get first order partial derivatives of the quadratic cost functions of all > generators with respect to pg. then in the obtained equations substitute > Optimal values of pg to obtain LMPs. > --- > > From: Ray Zimmerman <[email protected]> > To: MATPOWER discussion forum <[email protected]> > Sent: Thursday, 28 February 2013 9:14 PM > Subject: Re: performing lmp calculation > > If your OPF solution matches MATPOWER's OPF solution, then you can simply use > the LMP values computed by MATPOWER's OPF, found in results.bus(:, LAM_P). If > your solution does not match, then I'm afraid it's up to you to demonstrate > that it is even a solution to the OPF problem, i.e. that the optimality > conditions are satisfied. Not sure how MATPOWER can help you here. > > -- > Ray Zimmerman > Senior Research Associate > 419A Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > > On Feb 28, 2013, at 4:00 AM, Khirad Dhabhar <[email protected]> wrote: > >> Hi guys. I am doing my mtech project. Now i have been able to successfully >> create an ABC(artificial bee colony) based algorithm to solve the optimal >> power flow. Now i require the LMP (lambda values) for my solution. How can i >> use mathpower to use my opf results to calculate the LMP values. >> >> Thank you >> >> khirad >> >> >> -- >> Friendship is like a red rose with a green stem > > > > > > > -- > Friendship is like a red rose with a green stem > >
