Distribution System Security Region And Cross-sectional Studies With Transportation Network

The research of security region was first appeared in the field of power grid.As the security of distribution network does not involve complex stability problems,which is mainly represented by steady-state power flow,very close to the general network flow,the emergence of the security region of distribution network provides the possibility for the security region to be applied outside the power system.Any system needs to be able to function properly when a component fails.The urban transportation network not only meets the physical network connection between the starting points,but also bears the transportation,environmental factors and social public events.This article chooses the transportation network as the cross subject,and tries to apply the theory of security zone to the transportation network,and compares it with the existing methods in the transportation field.The article compares security region of transportation network with security region of distribution network to help us understand the essence of distribution network security region better.Firstly,based on the existing model of security region of distribution network,and the characteristics of transportation flow redistribution in N-1 transportation network,the model of security region of transportation network is proposed.In this paper,the security boundary distance of transportation network is defined,through which to determine whether the transportation network conforms to the N-1 security status,in order to obtain N-1 security evaluation method based on the security region of transportation network.Secondly,this paper verifies the transportation network security region method through a simple example.We first propose security region expression of transportation network,and then take the security operating point,unsecurity operating point,and critical point.Images of security boundary distance and security region from three different conditions are obtained,and the paper explains the security evaluation method based on security region by comparision.Thirdly,this paper compares the existing evaluation methods with the transportation network,and explains the rationality of the security region method.This design uses the user equilibrium method to study the redistribution of N-1 transportation under three different operating points,and to observe whether the distribution meets the security requirements.The whole process is completed by comparison with the vunlerbility of the transportation network.Fourthly,based on the theory of security region of transportation network,the preventive control method of transportation network is put forward.The congestion control of a single section extends to the congestion control of the whole transportation network.We make congestion control at unsecurity operating points so that it reaches a new security state.The upcoming operating point which is outside the security region could pass through the security region boundary and then move into the security region.Finally,this paper applies the security region theory to the actual transportation network,and compares it with the algorithm of the security region of distribution network.This design selects American Sue Fowles transportation network.Three different security border and security region images are obtained,and a security evaluation method based on security region is obtained.Block the unsecurity operating points so that they are moved from the outside of the security region to the inside.Through this method,the security region theory of distribution network can be realized in urban transportation network,which provides a new method for analyzing the stability and security of urban transportation network.