Comprehensive Evaluation And Decision-making For Transmission Network Planning Alternatives Based On DEAHP Method

Transmission network planning is an important part of power system planning and plays an important role in protecting power system stable development. A perfect planning scheme needs to meet the economic, reliability, security, flexibility, adaptability, and many other requirements. However, due to the complexity of the problem, the current transmission network planning not yet has all of the constraints into a planning model to consider. Therefore, the current transmission network planning typically is divided into two stages, establishing optimal model to get the alternatives and comprehensive evaluation and decision-making. The quality of planning scheme is closely related to the credibility of the results of comprehensive decision-making. Therefore, the study on comprehensive evaluation and decision-making is of great significance.First, as the current transmission network planning index system is not comprehensive enough, this paper establishes an index system all-round fully reflecting the requirements of transmission network from four aspects, technicality, economy, environment and adaptability in the premise of fully considering dynamic security, rationality of short circuit capacity, electromagnetic environmental impact and land resources. Then this paper does a detailed analysis on the calculation of each index, laying a strong foundation for the comprehensive evaluation.Second, because the methods applying in transmission network planning evaluation are mainly single subjective evaluation methods or single objective evaluation methods currently and on account of the shortcomings of the subjective disturbance of subjective evaluation method and not meeting the actual situation of objective evaluation method, this paper presents a new way of transmission network planning evaluation by means of combined evaluation method DEAHP. DEAHP method brings in the subjective AHP restraint cone based on an objective assessment making the perfect combination of objective and subjective evaluation. Case systems verified that the method is effective. Based on the above theory, This paper also developed a comprehensive program which the combination of transmission network planning and evaluation and decision-making of planning alternatives by MATLAB language developing correlation algorithm, Visual C++developing interface, and Access for the database. This program provides an efficient and convenient transmission network planning tool for the planning staff.At last, in view of the advantage of the comprehensive evaluation method dealing with the indexes of different nature, This paper also does a primary exploration on transmission network optimal planning based on the comprehensive evaluation theory hoping that the future planning models can be more inclusive of many indexes and more reasonable and credible.