Research On The Classification And Localization Of Single Frequency Voltage Sag Based On S Transform

At present,the voltage sag caused by equipment failure and the increasing number of power complaints,has become one of the most important power quality problems.Accurate classification of voltage sag and positioning is very important,it contribute to the prevention and control of voltage sag,for the development of mitigation strategies and provide a basis to solve the supply and demand sides dispute.This paper studied a method commonly used in voltage sag.In the S transform calculation of single frequency point and the optimal window width window by Gauss in the process of solving the only fundamental frequency point vector according to the signal spectrum,combining the characteristics of voltage sag,voltage frequency analysis method is put forward for single sag based on S transform.Taking the most common four kinds of voltage sag as the research object,the extraction and analysis of the characteristic value of the voltage sag signal are extracted and analyzed,and the classification of voltage sag based on single fundamental frequency S transform is realized by using decision tree.Secondly,aimed to study the disturbance source location of voltage sag,using simulation software MATLAB/SIMULINK to build the four kinds of voltage sag disturbance source model,the single frequency cross S transform to get the instantaneous apparent power monitoring voltage and current signals collected,according to the disturbance power calculation formula to calculate the disturbance power,using perturbation power criterion location of voltage sag disturbance source.Finally,two TMS320F28335 DSP is selected as the core chip,and the peripheral circuit and software implementation process of the voltage sag analysis system are completed.Through the single frequency analysis of S transform in the simulation of voltage sag classification and localization,verify the single baseband S transform in feature extraction and the superiority of the voltage sag,less time consuming,high accuracy,dynamic real-time compensation for power quality laid the foundation;and the design of the voltage sag analysis system,can classification and location of different types of depression,has the reference value in the practical application of engineering.