Smart Grid Fault Location And Line Monitoring System

With the rapid development of the power industry, power system continues to expand thescale, the transmission power and transmission line voltage level is continuously improving,and the amount of the transmission lines with high voltage and long distance is gradually in-creasing. If the high voltage lines in the event of failure will cause a great loss，so we need therapid, reliable and accurate fault location based on travelling wave for the high voltagelines.At the same time over-voltage factors seriously affect the safety of electrified wire net-ting. On over-voltage in power grid on-line monitoring, real-time access to power gridover-voltage waveform and its characteristic parameters, for power grid accident cause analy-sis, enhancing the insulation configuration has a very important guiding role.On the one hand, the accurate fault location system for transmission line fault point canbe shortened the time, save a lot of manpower and material resources; on the other hand theaccurate fault location system can be found in the line fault point, early treatment of blackout,ensure rapid restoration of power supply, reduce the economic loss caused by power failure.Therefore, the transmission line fault location system with great social benefits and economicbenefits, it is an important technical and economic significance of the research topic. Trans-mission line transmission power and voltage grade rises ceaselessly, ultra high voltage trans-mission line (special) has become the backbone network in electric power system, powersystem plays a very important role, it is on the safe operation of the power system plays animportant role, so the extra high voltage transmission line on relay protection and safety de-vice raised taller requirements. Transmission line failure, can quickly and accurately judgingthe fault type and fault point location determination, to ensure the reliability of relay protec-tion device, the speed, selectivity, as well as the power system safety and economical opera-tion has very important significance.This paper makes a study of the most common transmission lines of short circuit faults inthe power system, and deeply compares and analyses the principle of method algorithm andapplying conditions for kinds of the fault location.According to fault signal characteristics inthe transient process, made a C line based on wavelet fault location method, and uses wavelettransform and signal singularity detection principle.combined with the transmission lines faultwave current signal lines components of the mould modulus maxima properties, and putsforward a single wave speed fault locating method not affetcted by the travelingwave speed.The principle of the fault signal monitoring system of relay circuit: is the use of thephysical mutation of the protected equipment, and when the mutation reaches a certain value,through the logic part,issued the corresponding trip pulse signal. The fault signal monitoringsystem will Proeess the corresponding pulse signal, in which the core is the use ofSCMC(AT89C51),the output is light alarm,and in use of LCD to display when the failure occurred,so that staffs could accurately identified failure to make timely repairs.EHV transmission lines model with distributed parameter is set up by MATLAB and therunning of the ten short-circuit fault is simulated. Ultimately, the simulation results show thatthe methods of fault phase selection and fault location are not affected by the operation modeof system.