Fault Diagnosis for Grounding Grids Based on Tabu Search
Wang Jian-xin · Gao dianya jishu · 2007
A Tabu search based approach to diagnose the fault of grounding grids is presented.Shifting the positions of the current exciter within the touchable nodes and measuring the voltages between touchable nodes,the information of the grounding grid is remarkably increased.The index of the proposed method is to minimize the summation of the squared errors between testing voltages and evaluation values.The proposed Tabu search starts with the initial values of the designed resistances of the branches of a grounding grid.A tabu list is formed for the branches.In each iteration step,a set of neighborhood is formed by increasing or decreasing the resistance of each branch at a certain level respectively,while the other branches are not changed.The optimum one in the neighborhood without being tabooed is selected to be the solution of the corresponding iteration step.The global aspiration criterion is adopted,as well.Experiments are made on a grounding grid with sixty branches.A current exciter of 10A is injected at fifteen positions.Eighty-nine voltages between touchable nodes are measured.The diagnosis results show that the proposed approach is feasible and also has the advantage of not sensitive to the testing error.