Research On The Cluster Partition Of Active Distribution Network Based On Multi-time Step Rolling Optimization

Dividing the complex active power distribution network into multiple smaller and simpler areas is an important way for active power distribution networks to reduce the difficulty and dimensions of control.The active distribution network is divided into multiple clusters,and each cluster is regulated as a whole,which is conducive to the hierarchical partition control of the active distribution network.Based on this,this paper explores the problem of cluster partitioning in active distribution networks,mainly including the following aspects:(1)The branch cut enumeration method is used to solve the cluster division of the active distribution network.Including the use of second-order cone relaxation programming to solve system power flow.The active power distribution network is abstracted into a graph,and the breadth-first search algorithm is used to search the graphs of each cluster partitioning scheme to obtain the information required for cluster partitioning.Calculate and compare the optimal cluster partition scheme.Prevent the nodes in the cluster from being disconnected.It can also ensure that there are no duplicate nodes in each cluster and between different clusters,and that all nodes are included in the divided clusters.(2)This paper proposes an active distribution network fixed cluster partitioning method considering the communication facilities planning.Based on the communication investment,the power supply rate of the cluster,the power interaction between the clusters,and the control dimension,an optimization model of the active power distribution network cluster partition is constructed and solved to obtain the cluster partition scheme that optimizes each indicator comprehensively.Simultaneously,the results of different objective functions and the sensitivity of the parameters were studied using simulation.The simulation results show that the parameter setting and the weight of each objective function have a great influence on the cluster partition result.Therefore,the objective function weights and parameter settings need to be determined according to actual conditions and needs.(3)The status of the active power distribution network is constantly changing,and the stable cluster partition result are difficult to meet the operation control of the changing active power distribution network..Based on this,for the dynamic cluster partition of the active distribution network,the multi-time step rolling optimization is applied to the dynamic cluster partition of the active distribution network.Taking into account the uncertainty of the system,a dynamic cluster partitioning method for active distribution network based on multi-time step rolling optimization is proposed.Considering the power supply rate of the cluster,the po wer interaction between the clusters,the control dimension,and the change of the cluster division result,an multi-time scale dynamic cluster partitioning optimization model for active distribution network is constructed and solved.Based on the forecast error probability distribution model of each uncontrollable unit,the Monte Carlo sampling method is used to obtain the initial scene set of each uncontrollable unit,and the two-stage synchronous backward substitution method is used to reduce the initial scene set to obtain the typical scene set of the active distribution network.The system continuously scrolls for optimization and performs feedback correction in a shorter period of time,effectively tracking changes in the actual operating conditions of the system,and getting rid of the adverse effects of forecast deviations and distributed energy fluctuations on the active distribution network cluster division.Its ability to resist interference is strong.The validity of the proposed dynamic clustering algorithm is verified by simulation.