Research On Generation Companies' Optimal Bidding Strategies And Related Issues With Transmission Congestion Influence Taken Into Account

The power industry worldwide is experiencing unprecedented restructuring for breaking traditional monopoly, introducing competition and establishing electricity markets. In the electricity market environment, for maximizing their profits, generation companies as independent economy entities need to submit their bidding strategies to market operators. In the new electricity market environments, profits of generation companies depend, to a large extent, on bidding strategies employed. Hence, this dissertation focuses on the study of optimal bidding strategies of generation companies.Developing bidding curve of generation companies is based on their cost curve. First, this paper presents the cost curve of units, and then bidding rules in day-ahead markets. Based on these, the method of developing bidding curves are presented.In the paper, generation companies build optimal bidding strategies by estimating rivals'bidding strategies. When a transmission congestion occurs, which is due to the transmission capacity shortage of the power system, some electric power which succeeded in bidding could not be transmitted because of the congestion, and some others which failed in bidding because of overbidding need be transmitted. Thus the generation companies'optimal bidding strategies are according influenced. So it is worthy of studying how to build generation companies'optimal bidding strategies with congestion influences taken into account. In this paper, a two steps optimization model is proposed to solve the problem. At the first step, by estimating rivals'bidding an optimal bidding strategy is solved to maximize its profit, and at the second step, sensitivity sizes based adjusted outputs of generation companies are solved for minimizing the congestion cost, then a genetic algorithm is proposed to solve the optimization problem. Finally, the modified IEEE14-bus system is selected to show that the developed method can be used to instruct generation companies in bidding strategies.The transmission congestion will result in the rise of price in the electricity market, and generation companies adopt commonly bidding strategies for maximizing their profits. To prevent generation companies from driving price up, we must build rational congestion cost allocation strategy. As a basic study, this paper summarizes congestion management models under different power market modes, and congestion cost allocation method.