Detecting And Analyzing System Of Voltage Sags

Voltage sags occur more frequently with the development of power system. Thyristors are used wildly in the power system, computer-based devices applied to many fields by different customers, meanwhile the thristors and computer-based devices are sensitive to voltage sags. The arithmetic are discussed, the recursive complex wavelet is selected to analysis voltage sags by comparing to the others arithmetic in this thesis. Entropy is applied to find the proper wavelet scale parameter, with which the analysis results are more precise than with other parameters. LabVIEW language is used to program Virtual Instruments for detecting and analyzing the voltage sags in this paper. The actual running result proves that the entropy-based recursive complex wavelet arithmetic is effectively on analyzing the voltage sags. In the virtual instrument we programmed, real time monitoring the voltage sags, automatic generating report, querying the malfunction report is realized too. Sun xiaolong (Electrical engineering theory and new technology) Directed by prof. Li Baoshu...