Research on Fault Risk Ranking and Screening of Distribution Network Based on Uncertainty Theory

Abstract

With the rapid development of the national economy, the distribution network is becoming larger and larger, and the wiring is becoming more and more complicated. The power supply enterprises and power users are increasingly demanding the reliability of the distribution system. The distribution network is at the very end of the power system and supplies power directly to the power users. According to statistics, about 80% of users' power outages are caused by power distribution system failures. According to the results of risk assessment of distribution network, it is especially important to screen the risk of the most likely failure and prevent and control it to improve the reliability of power supply. The amount of information obtained from the risk assessment calculation is very large. For risk online prevention and control, it is impossible to conduct online risk prevention and control analysis for all assessment results. It is necessary to select the most serious risk information from the massive result data, and then trigger the risk online. Prevention and control measures reduce the risk level to a certain extent. The ranking and screening of previous risk assessment results are based on the performance index method and belong to the deterministic research category. Based on the uncertainty theory, this paper sorts and screens the fault risks to determine the risk with the highest level. For the fault risk of the top sorting, the precaution can be taken before the fault. For example, the power distribution network can be reconstructed, the islands are divided, and the DG is re-scheduled to minimize the loss. Finally, the reliability of the algorithm is verified by actual example analysis.