Online Identification Scheme for Short Circuit Ratio Based on Filter Extraction and Sliding Window Algorithm
With the threat of weak grid stability brought by the trend of"High Proportion of Renewable Energy and High Proportion of Power Electronic Equipment"to the power grid,in order to achieve real-time monitoring of power grid strength,the online identification of short circuit ratio is necessary.It is needed for many identification methods the design of complex harmonic extraction algorithms or the use of high-precision and high-speed sampling and analysis instruments,which is difficult to operate and costs more.To reduce the difficulty of identifying short circuit ratio,a disturbance response component extraction method based on filtering characteristics and a data outlier group sliding window filtering algorithm were designed,and a 2.5 MW wind turbine grid connection model was built.The simulation results show that the identification error of the short circuit ratio is within 5%,and the identification data also has good stability and accuracy,verifying the feasibility and engineering application potential of the proposed scheme.