Strategies of Daily Economical Dispatch for Power Supply Company Considering Electricity Contract and Spinning Reserve

In the electricity market, the initial problem considered by the power companies is the security and economics of power system. Before the electrical transaction, the power companies not only consider the power plants’ competitive bidding spot price and volume, but also pay attention to the original purchase contract with the original power plants and the spinning reserve of power system. Therefore, it is necessary to coordinate the volumes among the contract bid, the competitive bids and the spinning reserve for the predicted generation volumes. Only in this way could protect the benefit of power plants, maximize the profit of power companies, make the power market steadily and power system securely, and carry out the purpose of power system restructuring and deregulation. Aiming at this, the paper puts forward a new model for the economically apportioning strategies among the competitive bids, the purchase contracts and the spinning reserve volumes. At the same time, a simplified model is taken for the seeking process. Linear Programming and approach based on phase-out were used to solve the model, and the process became simple and credible. The analysis of case based on Matlab6.1 proves this approach is simpler and more reasonable.