Open AccessThree-phase unbalanced voltage sag detection method based on morphological filtering
Author(s) -
Zhicheng Guo
Publication year - 2022
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2254/1/012035
Subject(s) - voltage sag , filter (signal processing) , voltage , transformation (genetics) , computer science , control theory (sociology) , harmonic , low pass filter , phase (matter) , three phase , mathematical morphology , electronic engineering , artificial intelligence , engineering , acoustics , computer vision , physics , image processing , image (mathematics) , power quality , electrical engineering , biochemistry , chemistry , control (management) , quantum mechanics , gene
In dynamic voltage restorer (DVR), accurate and fast voltage sag detection method is the key. However, in the case of three-phase imbalance, the traditional voltage sag detection method still has shortcomings in real-time and accuracy. Therefore, a voltage sag detection method based on morphological filter is proposed. That is, based on the commonly used dq transformation method, the morphological filter is used to replace the Butterworth low-pass filter to suppress the second harmonic generated by the negative sequence component after dq transformation in the case of three-phase imbalance, reduce the system delay and improve the real-time and accuracy of the detection method. The morphological filter is designed, and the appropriate structural elements and morphological transformation algorithm are selected. The results show that the morphological filter has good filtering effect and small delay, and can better meet the detection requirements of DVR.