Analyzing Electricity Market Equilibrium Considering System Operational Uncertainty And Network Constraints

At present, the electricity industries throughout the world are undergoing hugelyrestructuring. Competition has been introduced in order to improve investment andoperational efficiency. But the electricity market is an oligopoly in which the generationcompanies have market power, being able to determine the market price by strategic behavior.The analysis of possible operation results and strategic actions in the electricity market seemsconsiderably important. Game theory is thought of as a rigorous solution tool to analyze thebidding strategies in electricity markets. This research is important for both marketparticipants and regulatory entities, in that the former are interested in optimal strategies formaximizing profit, and the latter have the duty to design and monitor the markets to ensurefull competitiveness. But because the particular characteristics of an electric power system,such as transmission constraints, complicate the market clearing mechanism and process, it isdifficult to solve the market equilibrium problem.This dissertation focuses on issues of equilibrium analysis of the electricity marketconsidering system operational uncertainty and transmission constraints. The main work andcontribution are presented as follows:1. The Nash Equilibrium in electricity market becomes complicated when the networkconstraints are considered. The strategic behaviors of Gencos are simulated usingco-evolutionary computation and the solving system of polynomial equations is used tocalculate the market equilibrium. The performance of co-evolutionary approach isanalyzed by comparing the experimental results and market equilibrium in the paper. Anexperimental n-person game in network-constrained power market is investigated.Different experimental scenarios are formed by changing network parameters, Simulationresults show that the co-evolutionary approach converges to different results in differentmarket equilibrium conditions, and is important for finding and understanding marketequilibrium with network constraints.2. Uncertain factors in the planning and operation process of electricity system bring greatchallenges to the analysis of electricity market. Taking into account load uncertainty andrandom branch outage, the paper proposes a supply function equilibrium modelconsidering system operational uncertainty. In the market model, the possible systemscenarios are firstly identified to model the uncertainties. The associated profit in diversesystem scenarios is varied, a generation company (GENCO) faces with greatdecision-marking risks because of the probabilistic occurrences of different system scenarios. Finally the co-evolutionary approach is improved and employed to search forthe stochastic market equilibrium. A modified nine-bus system is used to illustrate theproposed market model and verify the effectiveness of the solution method.