Research On Comprehensive Evaluation Method Of Power Network Planning

Power grid planning plays a vital role in power system planning, the reasonable grid structure is prerequisite to ensure the safe and stable operation of the power grid and the people live and work in peace and contentment. Constructing scientific and effective power grid planning and comprehensive evaluation system, can better determine the comprehensive evaluation planning methods, better handling the relationship between the factors that affect the power grid. The choice method of power grid planning evaluation as a measure of the quality of power grid is very important. At present, there are many evaluation methods used in various fields, suitable for in the evaluation theory and method of power network planning is not mature and perfect, there are still a lot of problems in this fields,which needs further research.This thesis analyzes the existing problems, and establishes the index system of power grid planning, the comprehensive evaluation of power grid planning method. Firstly, In this thesis, based on the principle of the construction of indicators,in accordance with the requirements of the technical performance of the premise,in order to determine the optimal economic efficiency of the planning program for the purpose,so this thesis constructs the evaluation index system of power grid planning from three aspects:security, economy, and the coordination of the influence of the environment.In the early planning program,it is very necessary to consider the environment problems such as the land use efficiency of transmission lines and the land use efficiency of transformer substation.It is necessary to analyze the adverse effects of the planning scheme.From the root causes to reduce the negative impact of environmental factors in the power grid planning.Secondly, due to different indexes have different effects on different indicators of evaluation, so give different weights, index weight and reasonable weight for a comprehensive evaluation of the results has a crucial role. This thesis uses fuzzy analytic hierarchy process and improved the maximum deviation method combining the moment estimation theory of combination weighting method to determine the index weights based on the determination to the subjective and objective unity of index weights.Thirdly,in a uhv power grid project,this thesis proposed to use the method of minimizing the deviation coefficient to evaluate the different planning scheme.The evaluation results are compared with the results of principal component analysis and grey correlation method.Through analysis and comparison,the simple feasibility of the method of minimizing the deviation coefficient is proved.Finally, The proportion of environmental impact factors in power grid planning is getting bigger and bigger.After the planning scheme is determined,from three aspects of electromagnetic environment, sound environment and ecological environment, this thesis analyzes the impact of power grid planning on the environment,and evaluates the environmental impact of the environmental impaet.According to the typical point line method based on fuzzy membership degree, the scoring standard of environmental impact index is established. The scores of each index were calculated.By layer calculation, the results of the environmental impact assessment are obtained. Evaluation of the environmental impact of the power grid planning is conducive to the protection of the environment from all aspects, to achieve the priority allocation of resources, reduce the negative impact on the environment after the implementation of the planning program, thereby establishing a harmonious and civilized power grid.