Single-phase Ground Fault Line Selection Method Based On Transient Characteristics Of Underground Power Distribution Network

The coal mine belongs to the production enterprise which has the explosive dangerous gas material.It is generally used in the underground power distribution network to compensate the operation mode of the arc suppression coil.Due to the use of cable in the underground power supply,the capacitor current value of the system is increased,and if it can not accurately identify and cut off the fault line,long time to run,it is likely to cause two phase short circuit,causing the system tripping accident,not only affect the safety of the mine production,and even the life and safety of underground workers.As the fault occurs,the fault characteristic signal is weak and the influence factors are various,so the accuracy of the traditional fault line selection device is a difficult problem to be solved.According to the different types of fault feature extraction,the single phase grounding fault line selection is divided into steady state method and transient component method.However,the sensitivity of the steady-state component method is not suitable for the underground power distribution network.So this paper analyzes the characteristics of single phase to ground fault in underground power distribution network,and then summarizes the advantages and disadvantages of the traditional method,By use of the post fault transient characteristics of signal,the proposed based on dual tree complex wavelet transform of fault line selection protection method,improve various defects of traditional wavelet transform in the practical application,will be the successful application to underground distribution network single-phase grounding fault line selection in the field,and the electromagnetic transient simulation software EMTP-ATP simulation results verify the feasibility of fault line selection method and superiority of high accuracy.In the implementation of the method,a model is constructed based on the 920 T ARM framework for the single phase grounding fault line selection device for the S3C2440 microcontroller,and the software ?SC /-?design of the device system is realized.Finally,the whole process of the fault line selection is completed.