Research On Disturbance Signals Analysis And Application Of Power Quality Based On S Transform

In recent years, with the rapid development of power electronic technology, frequency conversion technology, computer technology, power quality problems become more and more serious. At present, the problem of power quality disturbances has become a core problem of quality of electric effect.Therefore, the detection and analysis of power quality disturbance signals, real-time monitoring, are necessary conditions for power governance. In this paper,the problems of the common power quality disturbances are analyzed and studied, a real-time power quality monitoring system was designed.The contents are as follows.First, the basic content and the research status of power quality disturbance were analyzed. The common methods of power quality detection were introduced, and the advantages and disadvantages of these methods were analyzed and compared.Without the harsh use conditions in the field of signal detection,it was easy to implement S transform. At the same time, the analysis results were intuitive and easy to understand. So the S transform was applied to transient power quality disturbance signal detection and analysis.Secondly, different power transient signal models were created, which were detected and analyzed by S transform. The results we can extracted from the S transformation matrix were the start time, end time,duration, frequency and amplitude of the signal. Meanwhile, we could also draw disturbance signal amplitude and frequency cueves, the time envelope curves, contours and other graphics, you could clearly see the basic characteristics of the signal through graphics. Using support vector machine(SVM), according to the extraction of feature vector, to be able to accurately determine the basic types of disturbance signal power.Through the simulation and error analysis,the results verified the effectiveness of the method.Finally,combined with the needs of the enterprise,a monitoring system of power quality disturbance signals is proposed,which consists of hardware and software components.The system can realize the power quality disturbance signals detection,analysis and classification,which makes the real-time monitoring of power quality come ture.