Real-time economic dispatch and reserve allocation using meritorder loading and linear programming rules

The author presents a real-time economic dispatch algorithm suitable for online generation control and for study programs. The method is based on the rules of linear programming and the classical method of merit order loading. The basis for the algorithm is shown as a natural progression of classical optimization algorithms. Comparison with linear programming is included to exhibit the flexibility of the algorithm. The inclusion of a constraint for a unit or for a system-wide margin (e.g. spinning reserve) is shown. The procedure is fast, in part because the simplex tableau is not explicitly stored. The method is shown in pseudo-code. This method is very suitable for real-time economic dispatch on any energy management system. The method requires little computer resource and is appropriate for personal-computer implementation as part of a back-up automatic generation control system. The algorithm has been tested on data provided by Indianapolis Power and Light Company and has been programmed on a 80286 personal computer     

Framework for energy brokerage system with reserve margin andtransmission losses

The power industry in the United States is presently participating in a changing business environment. While planning to meet future peak demand is still a concern, the efficient utilization of existing generation and transmission resources is fast becoming of primary interest. This interest suggests to move from cost-based market operations to price-based market operations. In such a business environment, a need for a mechanism to determine the pricing of various ancillary services is desired as the ancillary services go together with electrical power transfer. The proposed approach develops a novel method of pricing mechanism for reserve margins and transmission losses as a part of the overall transaction in an energy brokerage system. The brokerage model described in this paper is based on formulations using linear programming     

The implementation of an energy brokerage system using linearprogramming

The authors focus on the economics involved in energy transfers. The function of an energy brokerage system is to establish interchange schedules between participating utilities in such a manner as to maximize the resulting savings. A brokerage system that uses linear programming (LP) is presented to maximize the savings or profits to each utility subject to import and export constraints. The cost quotations can also be determined using an LP formulation. Two examples to illustrate this formulation are given     

Interior-point linear programming algorithm for auction methods

Interior-point programming (IP) has been applied to many power system problems because of its efficiency for big problems. This paper illustrates application of interior-point linear programming (IPLP) to auction methods. An extended algorithm of IPLP is developed and used in this paper. This extended IPLP algorithm can find the exact optimal solution (i.e., exact optimal vertex) and can recover the optimal basis. Sensitivity analysis can be performed after the optimal basis is found. The sensitivity analysis performed in this paper is increase in the bid price and increase in the flow limit of the transmission line. This extended algorithm is expanded from the affine-scaling primal algorithm. The concept used in this extended algorithm to find the optimal vertex and optimal basis is simple     

Application of auctions as a pricing mechanism for the interchangeof electric power

The expected move to a market-based electric power industry will significantly change electric utility operations. These changes will fundamentally alter the pricing of electric power. How this pricing will be accomplished is a key issue. Traditionally, embedded cost based methods have been used. Spot-pricing has received attention as a possible approach in a market-based electric power environment. Another market-based approach is the use of auctions. This paper presents the application of a sequential sealed-bid and sealed-offer auction to the pricing of electric power by using linear programming     

AGC simulator for price-based operation. II. Case study results

For pt.I see ibid., vol.12, no.2, p.527-32 (1997). This paper deals with an automatic generation control (AGC) problem in a deregulated industry. Through the passage of new public utility regulatory policies, the Federal Energy Regulatory Commission (FERC) encourages an open market system for price based operation. The FERC has issued a notice of proposed rulemaking seeking comments on various ancillary services. One of these ancillary services is load following. Part I describes the simulation models and software implementation of load following contracts in the new environment, and also developed a framework for new market structure to understand AGC implementation in the price-based operation. This paper reviews the case studies to show the modifications required of conventional AGC software for the new environment. Three sets of case study results are reported. The first and second case studies illustrate how to simulate bilateral and poolco based transactions respectively in the new market place. The third case study considers various (bilateral and poolco based) contracts existing simultaneously in the system. The simulation results illustrate that the tie-line flows due to increased number of various contracts will tend to cancel among each other     

Priced based operation in an auction market structure

Open transmission access is a new legal requirement within the electric power industry. Interchange will require evaluation of the existing conditions to determine if the product can be delivered at the time required and at the level awarded through the bidding or negotiation process. This paper seeks to identify the likely deregulation details for a full market implementation when native load is considered equal to any other third party load (comparability). This paper seeks to identify the technical issues, such as standards and algorithms, necessary for changing the national infrastructure from a vertically integrated industry to a horizontally integrated industry     

Auction implementation problems using Lagrangian relaxation

Lagrangian relaxation (LR) is used as an auction method for bidding in a deregulated environment. This paper focuses on the problems that occur while using LR as an auction method. Identical or similar units can prevent LR from finding the optimal solution. If the units are similar, LR may have trouble selecting some of them for the optimal solution. A feasible solution may thus not be found. Since a heuristic selection of which unit data to alter has to be applied, this is inequitable to the unit(s) not selected and may result in lawsuit(s). Because the dispatcher has to use heuristic selection, there is no “fair” solution to these problems. The authors suggest previously published methods to implement auctions. Sensitivity analysis has also been applied in this paper to show that the percentage difference of similarity between units may affect the solution found     

AGC simulator for price-based operation. I. A model

This paper deals with automatic generation control (AGC) in a deregulated electric industry. Through the passage of new public utility regulatory policies, the Federal Energy Regulatory Commission (FERC) encourages an open market system for price based operation. The FERC has issued a notice of proposed rulemaking seeking comments on various ancillary services. One of these ancillary services is load following. This paper suggests the modifications required in the conventional AGC software to prepare students to study load following in price-based market operation. The details of implementing an academic power system are used to highlight the differences between the AGC operation in a vertically integrated industry (conventional paradigm) and a horizontally integrated industry (new paradigm). The future business environment for electric utilities is incompletely defined as of this writing. Therefore, a framework for price-based operation is developed to assist students in understanding AGC implementation in the new market structure. The proposed market structure is kept generic enough to capture all possibilities in marketing load following capability