Research On Wide-Area Travelling Wave Fault Location Based On Optimal Configuration Of Measuring Points

In space the modern power system forms a wide-area system, and now when the transmission line goes wrong, the traveling wave method is the most practical approach which can quickly find the point of failure and ensure the system stability and reliability. With the rapid development of GPS technology, synchronized sampling is more and more accurate. And GPS becomes an important tool of unified timing in power system which could enhance the accuracy in fault location technology of wide-area system.Firstly, methods for fault location and algorithms of wide-area traveling wave at home and abroad are introduced, the transient characteristics of transmission lines are studied and analyzed in order to study the traveling wave propagation characteristics in the power lines; eliminating the influence of electromagnetic coupling is acquired by phase-mode transformation; through the relevant knowledge of wavelet transform is researched on, choosing the best wavelet basis is to recognize fault traveling wave front; finally, this paper describes an algorithm for determining the measurement points of the established system, on the basis of this, a new type of wide-area fault location method is elaborated, and the relevant simulation results are verified.In order to guarantee the maximum observability and optimal economy of traveling wave fault location in complex transmission networks, firstly in this paper travelling wave recorder(TWR) optimal configuration method based on the extended double-end fault location method is given. Assuming that the fault point have been known, the shortest path to each node of the system could be determined. Based on the principle that the existence of at least one pair of travelling wave recorder could realize fault location, a mathematical programming model for configuration optimization is established and the method of solving the model is determined. Finally, the optimal scheme of the travelling wave recorder is obtained.On the basis of obtaining the optimal scheme, in this paper, a new wide-area travelling wave fault location method is presented which contains two parts: the first part is the calculation of the initial fault position; the second part is the improvement of the precision of fault location method. Manhattan distance is adopted to find out the accurate measuring combinations, by which the preliminary fault location is calculated. Then the accuracy of the results could be improved by the fault-occurrence time which is calculated by the information of monitoring points and grid topology relationship. Finally, the error of the traveling wave arrival time of each measurement point is considered, which is caused by environment and communication delay, and then, the fault tolerance capability of the algorithm is verified.All simulations are carried out in PSCAD, the IEEE-30 bus system and the IEEE-57 bus system are built in order to obtain the synchronized fault signals. And then using the MATLAB programming to deal with the fault data to determine the fault distance. Simulation results are indicated that the presented method can realize high accuracy and have a good performance in fault tolerance as well.