Research on the County Adjustment Setting Integrated System Based on the Extension of Protecting and Coordinating Boundary

Abstract

In order to achieve the “first-class distribution network†construction goal, the original scheme focusing on the demand of the electric power system is changed into the other one combined with the user’s demand. The line instant protection instantaneous period is with a short delay in the setting value strategy, and coordinates with boundary switch protection. It extends the original protected boundary to important users downstream, and coordinates with the transformer substation upstream, forming a set of relatively constant value based on the substation transformer. At the same time, with the coordination of boundary switch, section switch of long transmission lines and its related protection section, the characteristics of the original protection scheme are overcome, namely, relying on the length of transmission lines and failure to guarantee the selective coordination because of the influence of the operation mode. On this basis, the “county adjustment setting integrated system†can be effectively achieved so as to realize the automation of distribution network setting management.