Soft open point (SOP) refers to a novel power electronic device installed in active distribution networks (ADNs) to replace traditional tie switch. When a fault occurs, power outage areas are formed after fault location and isolation, SOP can provide voltage and power support for the outage areas, which improves the power supply reliability of ADNs. In this paper, a reliability index calculation method based on fault incidence matrix is used to calculate the reliability indexes of nodes and system. The principle of reliability improvement based on SOP is described, and the influence factors of SOP affecting the reliability of ADNs are analyzed. Compared with traditional tie switch, the integration of SOP can effectively improve the power supply reliability of ADNs. As the impact of position and capacity of SOP on supply restoration, it also significantly influences reliability improvement. The analysis of reliability improvement based on SOP is demonstrated on modified IEEE 33-node system.
Keywords active distribution network (ADN), soft open point (SOP), reliability, supply restoration