| The high voltage transmission system is an important part of the national power grid.The normal operation of the high voltage transmission circuit directly affects the various links of the industrial production and the life of the residents.At the same time,the high voltage transmission circuit generally lay the distance,the long distance of the wiring path of the environment is relatively poor.Environmental factors,seasonal factors such as rain and snow will be the normal operation of the high voltage transmission line interference.Once the high voltage transmission line failure,can not work properly,the national power system security and stability of the operation of the impact is extremely serious.Therefore,the power system in the daily operation of the work must be able to timely and accurate fault detection of high voltage transmission line.The fault can get timely treatment,reduce the high voltage transmission line fault caused by the economic loss and social loss.Wavelet transform method is an effective technique in signal processing field.It is a kind of signal analysis and processing tool based on Fu Liye transform,which is widely used in signal processing field.Wavelet transform can effectively extract useful information from the original signal due to its flexible time frequency window.Therefore,the attention of scholars at home and abroad in signal analysis and processing.Its theoretical analysis and application areas are still more room for development.From this point of view,this paper applies wavelet transform method to the fault detection of high voltage transmission line,and the transmission line signal is separated by constructing the wavelet threshold function,which can determine the fault point.At first,this paper analyzes the traditional classic wavelet transform domain value function is soft and hard threshold of application and existing defects,and in the classical domain value function based on the theory and try to put forward a critical threshold denoising method.Through the simulation experiments verify the in this paper,the structure of the critical threshold denoising method can well overcome caused by soft threshold function with the original signal constant deviation shortcomings,also can make up for the hard threshold function leads to the incomplete removal of the inherent defects of the noise.Finally,this paper uses the Simulink simulation model to simulate the fault of high voltage transmission lines in noise environment,and applies this method to detect the fault of the high voltage transmission line.Through the theoretical analysis and simulation experiments results show that the critical domain in this paper,the structure of the value function can be more accurate positioning of the high voltage transmission line fault location,compared to the traditional domain value function detection method has better effectiveness and accuracy. |
