Multiple Time-scales Node Flexibility Evaluation and Partitioning Method of the Distribution Network Oriented to SNOP Integration

摘要

The penetration of renewable energy (RE) has been increasing in recent years, which leads to the increment of the uncertainty of the distribution networks, as well as the power quality problems. Many power electronic devices, such as soft normally open points (SNOPs), have been applied in the distribution networks to deal with the disturbances causing by RE and thus enhance the operation stabilities consequently. This paper presents a multiple time-scale flexibilities evaluation method for accessing the SNOPs into the distribution network. There are four sub-indicators are employed in the evaluation method, which are net load fluctuations, voltage deviations, distortion rate of harmonic voltage, and RE ramp rates. The subindicators are weighted by the information entropy weight method (EWM) under each typical scenario. Distribution network nodes are partitioned according to the evaluation results, which provide the access basis of SNOP. A case study is performed to show the nodes flexibility improvement of a distribution network with SNOP integrate.