Research On SNOP Planning Method For Coastal Distribution Network Under Typhoon Environment

The typhoon is a natural disaster with strong destructive power,and the distribution network is more susceptible to typhoon disasters.In recent yea rs,the distribution network has developed rapidly,and the topology of the distribution network has become more and more complex,which has brought severe challenges to the safe and stable operation of the distribution network.In order to improve the ability of the distribution network to self-repair in the typhoon environment,a method of using a soft normally open point(SNOP)to replace the traditional switch in the distribution network is proposed.SNOP has the function of regulating the flow in both directions,reducing the network loss,balancing the voltage and restoring the power supply.However,the cost of SNOP is relatively high,which limits the application of SNOP in the distribution network.Based on the role of SNOP to regulate the tidal current,after the fault of the coastal distribution network during the typhoon,the power supply can be restored via another branch.This way improves the self-repairing ability of the distribution network and improves the economy of SNOP.In order to evaluate the benefits of using SNOP to reduce network loss.In this paper,the network loss is listed as a nonlinear equation in the form of node injection power,which reduces the difficulty of calculating the network loss after adjusting the power flow.The scenarios of load and distributed power fluctuations in the coastal distribution network are analyzed in order to reasonably construct the distribution network operation scenario.According to SNOP and system operation state,the optimal value of network loss is calculated by MATLAB optimization function,and the influence of different installation positions and SNOP capacity on network loss optimization benefit is quantitatively analyzed.The fluid dynamics simulation software FLUENT is used to restore the nearsurface wind field of various scenes.The wind field obtained by simulating the typhoon sample is matched with the wind field obtained by the fluid mechanics simulation,and the proportion of typhoon samples with different conditions is counted.According to the topology of the distribution network,the conditions for restoring power generation are analyzed,and according to the exponential failure probability curve,combined with the near-surface wind field samples,the probability of regenerative power generation under various conditions is calculated.Finally,according to the isolated topology,the conditions for restoring power generation with multi-branch and the probability of restoring power generation are further analyzed.This article will roughly analyze the relationship between SNOP cost and capacity based on modular multilevel converter(MMC).Based on the economic losses caused by power outages in Fujian Province,analyze the benefits of emergency recovery power generation under multi-branch,combined with the reduced network loss benefits of this method,comprehensively consider the economics of SNOP,and complete the installation location of SNOP in the distribution network.With the choice of installation capacity.This paper establishes a SNOP planning method for coastal distribution network in typhoon environment.From the aspects of reducing network loss and emergency recovery of power supply during distribution during typhoon,the economics of SNOP are studied comprehensively.The research results obtained from the study are more reasonable and can provide some help for improving the self-repair ability of the coastal distribution network.