Fault Detection Of HVDC Transmission Line Based On Improved Blackman Window

The development of HVDC transmission has attracted much attention in recent years.High-voltage transmission lines are the lifeline of the power system and are indispensable and most vulnerable components.They are responsible for the heavy tasks of transmitting electric energy.Once a fault occurs in the transmission line during operation,its impact seriously threatens people's economic life and other aspects.How to quickly and accurately determine the time of fault occurrence and accurately locate the fault point in the event of a fault in the transmission line,and quickly remove the fault point from the power system has gradually become a major research topic of modern power systems,with important Explore meaning.In this paper,for HVDC transmission lines,the status quo and development trend of research methods for line faults are first outlined.Based on the analysis of the process of DC line faults,the concept of travelling waves is introduced,and the principle of traveling wave protection is further elaborated.Then,when the fault signal is detected,the wavelet analysis technique is introduced.Based on the singularity detection of wavelet and the modular maxima theory,the improved Blackman window function is used to achieve a better detection of the no-fault fault signal and the wavelet.The modulus maxima are detected to detect singularities to locate the fault location.Finally,the MATLAB/SIMULINK model of HVDC power transmission system was established.The faults were simulated by two different methods,namely single-end reverse traveling wave method and double-end forward traveling wave method.By using these two methods to simulate and analyze various influencing factors and different faults,it is concluded that various influencing factors do not affect the conclusion of the detection of the modulus maximum of the wavelet transform and realize the fault of the HVDC transmission line.Accurate detection,positioning and protection.