Simplified model of distribution network based on minimum area and its application

The distribution networks feature diverse range of equipments and wiring, and the modeling and techniques are essential to the construction of distribution automation. The modeling of power system are mature, and the modeling method is very useful for analysis of power grid. Thus, the modeling of power system are used in the transmission network, which is established based on study on the structure and characteristics of transmission network, and applied successfully in the transmission network. However, it is not much convenient for the distribution network, which will lead to complex model, large admittance matrix, huge storage space and enormous data processing workload. A simplified model of distribution network based on the minimum area is proposed in this paper. A region means power supply range of distribution network, consisting of following primary equipments: feeder segment, switch, bus segment, transformer and load etc. A minimum area means a minimum power supply area for controlling and operating of distribution network, excluding inside switches, and the operating status of the internal equipment is consistent (online or offline), so it's the smallest unit for controlling and operating of distribution network. Based on the model of minimum area, a fault diagnosis and location algorithm is developed for distribution network, especially for operating of loop distribution network or with distributed power supply. Moreover, an optimum recovery program for fault downstream power supply interrupted region is introduced. The simplified model of distribution network based on the minimum area and the fault diagnosis and location algorithm thus developed is very important for applicability and practicality of projects to promote the distribution feeder automation.