Study On Disturbance Source Location In Power Systems Based On Frequency Dynamic Response Date

One distinguishing characteristic of the large-scale power grid is that the probability of chain failure caused by local disturbance in power system increases day by day,which seriously affects the reliability of system operation.At the same time,the wide application of synchronous phasor measurement unit indicates that the frequency dynamic spatial-temporal distribution characteristics caused by disturbance becomes a prominent feature of large-scale power systems.The wave theory provides a new idea for the disturbance source localization by analyzing the generation mechanism of frequency dynamic space-time distribution and the law of disturbance propagation.It is feasible and necessary to locate the system disturbance source from the perspective of disturbance propagation.In this paper,the frequency dynamic spatiotemporal evolution model in uniform chain system is established for the frequency dynamic characteristics.The propagation characteristics of frequency fluctuation induced by electromechanical disturbance in simple system are described,too.On this basis,considering the influence of generator inertial distribution on disturbance propagation,based on the topology of power grid,the power system frame structure model is established.In tur,the equivalent action mode of generator inertia in the scope is discussed,and then disturbance propagation velocity formula is derived,which takes into account the position information.Then the paper gives the optimal configuration scheme of the detection device.And this paper studies the Floyd algorithm,which solves the shortest propagation path of any two points in the system,to determine the propagation path of initial disturbance when there are multiple branches between the two units in the complex network structure.The paper points out that the generator,monitoring device and other components can be abstracted into points in the geometric plane.The process of the disturbance source positioning is the process of determining the position of the point to be sought with the known velocity,propagation time,propagation path and reference point position.Finally,the paper analyzes the basic plane positioning method and frequency dynamic space-time distribution characteristics.And based on the hyperbolic intersection location method,the disturbance source localization in power systems,by time difference of arrival,is proposed.The validity of the disturbance arrival time difference location method is verified by the 3-machine 9-bus standard system and the off-line data of Yunnan Power Grid on the PSS/E simulation platform.The results show that the proposed positioning method can guarantee the reliability and accuracy of the disturbance source location within a certain range with using less monitoring devices.