Transmission congestion management in competitive electricity markets

Abstract

Abst~act: This paper studies the management of costs associated with transmission constraints (i.e., transmission congestion costs) in a competitive electricity market. The paper examines two approaches for dealing with these costs. The first approach is based on a nodal pricing framework and forms the basis of the so-calledpool model. The paper also provides an analysis of financial instruments proposed to complement nodal pricing and includes illustrative test results on a large scale system. The second approach is based on cost allocation procedures proposed for the so-called bilateral model. The paper explains the basis for this model including a game-theoretic evaluation of some of its aspects. Both the pool and bilateral models have been at the center of the electric utility restructuring debate in California.

Genetic Algorithm Based Congestion Management by Using Optimum Power Flow Technique to Incorporate Facts Devices in Deregulated Environment

“…In a broader sense, congestion management is considered as a systematic approach for scheduling and matching generation and loads in order to reduce congestion [1], [2]. A bilateral transaction is made by a GENCO-DISCO pair without third party intervention while a multilateral transaction is a purchases and sales agreement between several GENCOs and DISCOs possibly supplemented by third parties, such as brokers or forward contractors [3], [4]. What is common between bilateral and multilateral transactions is that the quantities traded and prices agreed upon are up to market participants to decide and not a matter for the ISO.…”

A Comparative Analysis of Congestion Management Schemes under a Unified Framework

“…Typically, the various existing organizations have grid control but no grid ownership. A common need, however, for the restructured industry is that of operating the grid independently of the various market players [1], [2]. So as to avoid confusion we use the term independent grid operator or IGO to refer to the generic system operator organization and include under it the independent system operator (ISO), ransmission system operators (TSO) and regional transmission organizations (RTO) structures Congestion occurs whenever the system state of the grid is characterized by one or more violations of the physical, operational, or policy constraints under which the grid operates in the normal state or under any one of the contingency cases in a set of specified contingencies.…”

Coordinated spot market for congestion management of inter-regional electricity markets

“…The solution to the original problem (8) is obtained by solving a sequence of nonlinear problems of the form of (9). The sequence of barrier parameters monotonically decreased to zero as iterations progress, and it generates a sequence of subproblems as formulated in (9). The solution to these subproblems approaches , a stationary point of (8).…”

“…There is a universal lack of consensus on which model best addresses the problem of congestion management in electricity markets [8], and has been addressed from different perspectives [9]- [12]. It is important to differentiate between temporary and structural bottlenecks when selecting methods of managing congestion [13].…”

“…The nonnegative conditions on the slack variables are then appended to the objective function by using a logarithmic barrier term, that is minimize subject to (9) where is the barrier parameter, and is the number of inequalities constraints associated with . The solution to the original problem (8) is obtained by solving a sequence of nonlinear problems of the form of (9). The sequence of barrier parameters monotonically decreased to zero as iterations progress, and it generates a sequence of subproblems as formulated in (9).…”