The Research Of Island Fault Location Method Based On Improved Petri Net

With the full use of distributed generation,the stability of microgrid is very important.For the special structure of microgrid.When the public connection point is disconnected from the combined power grid,there will be isolated island operation.In order to solve the problem of inaccurate fault location of micro-grid caused by inaccurate action information returned by circuit breakers during unplanned islanding operation,an improved method for islanding fault location of micro-grid is proposed in this paper.This method plays an important role in reducing the time of islanding fault location of microgrid and improving the accuracy of islanding fault location of microgrid.Specific research contents are as follows:Firstly,analyzing the status of islanding fault location in microgrid from islanding detection and fault location.Different methods are classified and compared to clarify the background and significance of this study.Secondly,this paper analyses the actual islanding detection technology,compares the advantages and disadvantages of various methods.On the premise of eliminating the failure zone,improves the existing islanding detection technology to make sure,it can not only reduce the time of islanding fault location,but also reduce the impact on power quality.The method uses piecewise function to represent the added disturbance.Simulink module is used to simulate and verify that the improved method has less islanding detection time and THD rateFinally,an improved fault location method for microgrid is proposed.Based on the research of traditional Petri net fault location,and on the premise of the improved method mentioned above,improves the hierarchical Petri net used in islanding fault location.Layeres according to the number of main protection,and the fault location of microgrid under islanding operation is realized.The simulation is realized by using MATLAB programming and Petri net simulation software.The improved method is more reliable and uses a shorter time.