Research On Many-Objective Optimal Operation Of Distribution Network Based On Topology Reconfiguration

Distributed renewable energy is extensively employed in power systems to address the issues of resource depletion and environmental degradation.The power fluctuation and uncertainty of the distribution network are exacerbated by the widespread integration of renewable energy,leading to issues including power loss,voltage instability,and peak-valley fluctuations.Distribution network reconfiguration is deemed as a significant technical approach to minimizing power loss and enhancing the reliability of power supply since it entails no external equipment and incurs no additional installation expenses.How to suppress the adverse effects of random fluctuations in the distribution system based on topology reconfiguration technology and improve the flexibility of system operation is an important research topic in the field of distribution network.In light of this,the current paper principally investigates the optimal operation of distribution network based on topology reconfiguration.The detailed methodology is outlined as follows:Firstly,in view of the distribution network reconfiguration,given the considerable amount of calculations required for mathematical optimization methods,the sluggish convergence of artificial intelligence algorithms,and the unsatisfactory accuracy of heuristic methods such as optimal flow mode or branch exchange methods,a distribution network reconfiguration technology based on multi-step switching sequence exchange(MSSE)is proposed.The MSSE technology can be divided into three distinct steps.Initially,the operating state of the switch is determined using the optimal flow mode method,while the second and third steps involve correcting the switch’s operating state by utilizing the branch exchange method.Then,aiming to address the uncertainty of renewable energy generation in the distribution network,a coupling strategy that considers both active and reactive power based on joint probability is proposed.This strategy derives indexes for value of loss load and value of power curtailment.The influence of renewable energy generation uncertainty on the operation of distribution system is studied from the perspective of risk aversion.On this basis,a topology reconfiguration optimization model of stochastic distribution network considering power loss and risk aversion is proposed based on MSSE technology,which aims to realize the joint optimization of operation cost and power loss of distribution system.The effectiveness of the proposed MSSE technology and optimization model is verified by an example analysis.Finally,considering the multiple operational flexibility indexes of distribution network,a two-layer iterative stochastic optimization method based on multi-step reconstruction and multi-objective dimensionality reduction is proposed based on the uncertainty risk assessment of renewable energy generation.In the upper level,a distribution network reconfiguration optimization model based on MSSE is constructed,which aims at minimizing power loss.In the lower level,based on the topology obtained from the upper layer,a many-objective reduction optimization model is established to deal with the problems of multiple flexibility indicators dimension disaster and complex calculation.The effectiveness of the double-layer iterative scheduling in reducing network loss,improving voltage quality and peak load shifting is verified by simulation analysis on multiple IEEE benchmark test systems.