Study On A Decision-making Model For The Investment Allocation Of Power Distribution Networks

A distribution network is the link of terminal users and a power generation and transmission system,and also is an important part to ensure the safety and reliability of power supply for customers. With the continuous development of national economy, users’ demand for electricity increases by years, and power supply enterprises and relevant government departments increase investments for the construction of power distribution networks. It becomes one of important problems how to reasonably and effectively allocate a great deal of construction funds to each region of distribution networks in order to adapt local economy development.In this paper, a systematic decision-making model of allocating construction funds is put forward for the first time, and a corresponding software is developed, providing a reference for the distribution network investment decision-making of a power supply company, based on the objective to improve the investment benefit and balance regional distribution network development with the present situation of a distribution network and power demand change and market environment being considered.First of all, the concepts and calculation approaches of rigid investment, flexible investment, economic investment, and upper and lower investment limits are proposed for distribution network investment allocation decisions of each region, and a relational expression of transformation ratio is deduced, which involves the equipment service life and load growth rate. The rigid investment is to satisfy the existing and new power demand and the most basic construction requirements; the flexible investment is the power supply company’s approval total of investment minus the rigid investment; the economic investment is the maximum investment with the energy sale, electricity prices and internal rate of return being known; the upper and lower investment limits are the reasonable investment range of each region.Secondly, four kinds of practical models of allocating flexible investment are put forward, which include the allocation models of equal yield proportion, rigid demand, energy demand and hybrid with the upper and lower investment limits being satisfied for each region.Then, based on the proposed models, the corresponding distribution network investment decision-making software is developed from the perspective of power supply enterprise application, which has a convenient and flexible interface and function design to users.Finally, the proposed model is applied to the distribution system investment allocation for a province of 15 cities, with the analyses for the last year investment allocation and reasonable suggestions for future investment allocation being shown. The real example shows the rationality, the effectiveness and practicability of proposed model.