Hi, Does someone knows how to use the script psse2matpower to translate PSSE data to matpower Data, I have tried matlab function perl without results. I appreciate any help thanks
________________________________ From: [email protected] [mailto:[email protected]] On Behalf Of Santiago Chamba Sent: Monday, May 16, 2011 8:50 AM To: 'MATPOWER discussion forum' Subject: RE: Mistake_Auctions Thank very much Proffesor Zimmerman. First instance, I am going to try construct a user cost function, then, I will inform you about the results. If this approach does not work, I would appreciate explain me your idea complicated. Thanks De: [email protected] [mailto:[email protected]] En nombre de Ray Zimmerman Enviado el: viernes, 13 de mayo de 2011 18:31 Para: MATPOWER discussion forum Asunto: Re: Mistake_Auctions If you construct a user cost function (section 5.3.1 of the manual) with an N matrix that gives you an r vector equal to the flows, you should be able to put appropriate costs on them. If that approach doesn't work, I have another more complicated idea that involves splitting each branch so it has two dummy nodes in the middle, then add some dummy generators and some constraints at the dummy nodes. -- Ray Zimmerman Senior Research Associate 211 Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On May 13, 2011, at 1:23 PM, Santiago Chamba wrote: Thank Professor Zimmerman for your explanation. Now I have very clear my bug. I have a new question. I want to modify the objective function, because I need to introduce transmission auction in the day-ahead market (Offer and bids). For my case, I must to introduce the transmission offer and the transmission cost, i.e., my objective function is: Minimize : Price(transaction)*P(transaction) + Cost(transmission)*fk) Subjet to Nodal balance equations: [Pg-Pd]=[B][Teta]=[=[IT(transaction]*P(transaction) Transmission limits: (-fk)max< fk <(f k)max Where: Price(transaction): offer price ($/MWh). If transaction is an extraction request (demand), the price (positive) will be the maximum price that the bidder is willing to pay for the purchase of energy. If transaction is an injection offer, the price (negative) will be the minimum price that the bidder is willing to receive for the sale of energy. If transaction is a request for transmission services between two nodes, the price (positive) will be the maximum price that the bidder is willing to pay for the requested transmission services. The algorithm determines the optimal dispatch of the opportunity bids and offers and the optimal allocation of transmission services, and produces buying/selling opportunity prices (nodal prices) and transmission services prices (differences of nodal prices). Then, I need to introduce transmission limits in two directions and modify the objective functions to consider the transmission cost and the services transmission offer. I do not know, If the characteristics above mentioned are possible introduce in Matpower?, Otherwise ¿Could I use some Matpower's files for Objective? Best regards De: [email protected] [mailto:[email protected]] En nombre de Ray Zimmerman Enviado el: jueves, 12 de mayo de 2011 16:13 Para: MATPOWER discussion forum Asunto: Re: Mistake_Auctions I am assuming you are running this with offers/bids defined by what is in gencost. In the first case, the incremental cost of generation between 50 MW and 100 MW of output is $15/MWh. Likewise the incremental benefit for the load between 60 MW and 90 MW is also $15/MWh. For the (lossless) DC OPF problem, this means that the objective function value does not change as the dispatch changes between 60 and 90 MW ... i.e. for the exact bids and offers you are using there is no unique minimizing solution to the DC problem. For the AC problem, the losses create a small price difference between the buses, eliminating solutions with greater than 60 MW of demand, so there is a unique solution. In the case with the line constraint at 50 MW, once again, you are creating an anomaly by setting the constraint value to fall *exactly* on the corner point of the generator's cost function. If you set it to something slightly less than 50, then the prices will be pretty close to the expected $10 and $18. If you set it slightly greater than 50, then the prices will be $15 and $18. Strictly speaking, the node 1 price for a line capacity of exactly 50 MW is not uniquely defined. It can be anything between $10 and $15. Hope this helps, -- Ray Zimmerman Senior Research Associate 211 Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On May 12, 2011, at 12:58 PM, Santiago Chamba wrote: Dear Professor Zimmerman, I think that there is a probable mistake in the auction method (smartmarket), specifically in DC OPF. I run a smartmarket and OPF (DC and AC) without fixed load, i.e., the two nodes system only has generators offers and demand bids (inelastic). When, I run AC OPF the results are correct, but with DC OPF the results may be wrong, because the inyections and extractions electricity are very different to the AC responses: Node DC OPF DC OPF Pot Lambda Pot Lambda MW $/MW MW $/MW 1 70.8298 15 60.0394 15.00 2 -70.8298 15 -60.0067 15.016 I think the correct responses for DC OPF is 60 MW in the two nodes. Why are the AC and DC results so different? When, the capacity line decreases to 50 MW, the inyections and extractions electricity are correct, but the prices changes: Node DC OPF DC OPF Pot Lambda Pot Lambda MW $/MW MW $/MW 1 50 11.32 49.99 10 2 -50 18.00 -49.97 18 I think the correct responses for DC OPF is 10 and 18 ($/MW). Why are the prices (AC and DC) in the node 1 so different? Please, explain me What is my mistake? or Where can I modify the mistake?. Because I need the model for my investigation. Thank <subasta.m>
