The Research Of Power Quality Detection Based On Embedded Technique

With the electronic devices and other nonlinear loads used in power network, the nonlinear, the instability and the unbalance of the voltage have become more and more serious. By the on-line and real-time monitoring, recording and analysis, the necessary evidence can be provided to improve the power quality, formulate correlative solve measure; establish technical parameters of controlling device.Firstly, this paper introduces the definition about power quality, classifies power quality phenomena, and explains the cause of power quality. Then the wavelet transform is discussed. This section explains the theories and how to use the theories in power quality analysis. Four common power quality transients, namely voltage sag, voltage swell, voltage interruption and surge are described carefully. And summarize the methods of analyzing the power quality transient problems. The following respect is the research on the detection and analysis of power quality transient.This paper adopts a novel digital signal processing method—the wavelet transform. According to the non-steady characteristic of power quality, the good time-frequency localization makes the singularity of signal can be signified as the wavelet transform modulus maxima. Using Mallat algorithm, the wavelet transform modulus maxima of singularity is extracted through Multi-solution analysis. By which, the accurate localization of fault signal can be realized, the duration and amplitude of which can also be obtained.This meter adopts advanced and reasonable framework of super stratum plus substrate machine, embeds Linux operating system and QT, 32 bit high speed float DSP sample data, through HPI bus interface data are sent to Embedded industry control computer based PC/104 bus, are analyzed and processed by applications program, at last it realizes monitor and analyses function of high accuracy, multifunction.