Research And Design Of Data Processing System Of The Power Quality Monitoring Instrumentation

With the social development and scientific and technological progress, both in industrial production or family life, more and more high technology electrical equipment and devices will be used. This case gives people the convenience of production and life, while will produce all kinds of electromagnetic interference, causing harm to the power system to a certain extent, resulting in a decline in power quality, and these high-tech electrical equipment and devices demand high-quality power at the same time. To resolve this contradiction, the first thing to do is the detection of power quality, and then to seek to improve power quality. Today, how to improve power quality, to ensure safe and stable operation of electrical equipment, has become a focus of attention at home and abroad.This paper discusses the significance of power quality research and research status at home and abroad at the first time. The author studys the newly national standards of power quality industry issued in China on June 18, 2008, and raise the design proposal of data processing system of power quality measurement, and introduce it from algorithm, hardware design, software design this three aspects in detail.In the algorithm, the author introduces the power quality measurement method of voltage deviation, power system frequency deviation, three-phase voltage imbalance, voltage fluctuation and flicker. The research focuses on the detection methods of three-phase voltage unbalance degree, and proposes and designes a higher-precision FIR low-pass digital filter to reduce measurement error, with the ultimate goal to improve the accuracy of the detection of three-phase voltage imbalance and verifies its correctness by MATLAB simulation. In the hardware design, the TI's digital signal processor DSP is used for the core, peripheral circuits of digital signal processor, analog input and conditioning circuits and data acquisition and transformation circuit are designed. In the software design, through a special software development environment CCS integrated for DSP, three units are designed including the main program module, data acquisition module and data processing modules.The system accomplishes the acquisition of analog signals from power system and the conversion to digital signal suitable for processing DSP by the ADC, then do processing and computing of the original digital signal with the digital processor by a certain algorithm, to get the several parameter which reflectes the power quality.