Optimal approach on renewing framework for rural power network upgrading

The annual increase of electric load in rural distribution makes it necessary to renew framework during upgrading rural power network. Model for load forecasting was given, and adaptability of power network was defined in this paper. According to the minimum and maximum load increasing rate, the minimum and maximum load were forecasted in the end of planning period, and adaptabilities of network were analyzed, and paths with bad adaptability were found subsequently. On the basis of satisfied voltage quality, minimum investment, and lowest power loss, the renewal schemes of network were determined. The method proposed was applied to a real grid example. By calculation, analysis and comparison, the results showed that the method can be used for confirming weak part of rural network, and determining the renewal scheme of frameworks. And also the results showed that the loss was significantly reduced, and the node voltage was greatly improved. The method can adapt to the renewal needs of multi-voltage level and multi-line rural network under the structure of radial grid.