The Study Of Differentiation Planning Model In Power System Under Disaster

In recent years, the influence of frequent natural disasters in power system has caused social attention to the capacity for resisting natural disasters. So from an overall prevention perspective, adopt the method of differential planning and improve the design standards of a part backbone of substation and line and attaches the great importance of the guarantee of power supply to the important load in the power grid planning stage has very important significance in improve the strong resistance and disaster relief of power system and reduce the damage degree caused by blackout accident and natural disaster in power system.Differentiation planning in power system is the important means of improve the ability to withstand natural disasters and reliability in power system, and credible load evaluation and prediction is the basis of the differentiation planning. This paper propose the load outage loss, return on investment, the close degree of node load center, expert rating four index as a special load evaluation index, and get the weight of each index by the fuzzy analytic hierarchy process. This paper building differentiated planning special load evaluation index system, which can quantitative load selection effectively.After get the special load of power grid in this region by assessment, this paper build the differentiation of transmission network planning model under special load node in particular disaster scenarios. This paper established transmission network planning model of special nodes without considering the disaster by introducing a probability of the electric power equipment damage in disaster scenario, using the load shedding of load node after grid planning and disaster emergency power load node increase power supply capacity economic cost minimum as objective function,and using branch power flow boundary, Kirchhoff’s law and the node output bound as constraint conditions. To proceed disaster reduction optimization in power grid better and have higher reliability, this paper established the differentiation planning model which in disaster when power grid optimization under the special nodes are not allowed to load and within the scope of the permit to cut part of the load. At last, this paper build a differentiation of transmission network planning model based on specific nodes in disaster which consider part of the power supply as a black start power supply.Based on the Matpower toolkit in Matlab software, IEEE-14 and IEEE-118 nodesystem are used to as an example to solve the established model. First of all, simplify the model, the complex constraint condition of reduction is simplified to equality constraints and inequality constraints and boundary constraint. Then separately calculated the result in disaster of power grid planning model that not considering of special nodes, differentiation of transmission network planning model that based on the special node haven’t load shedding, differentiation of transmission network planning model that based on the special nodes can cut part of the load shedding and the differentiation of transmission network planning model that based on of black start power supply. It is concluded that: not only verify the validity of the model, and can be very good provided data reference for the actual grid scheduling under disaster.