Research On The Power Quality Detecting Algorithms And System Development

In recent years, with the improvement of modern national economy and the progress of science and technology, people pay more attention on the power quality problems. To improve power quality first of all we must carry on the effective detection and analysis, it is need to effectively parameter estimation algorithm. Power signal is complex, Measurement accuracy and speed requirements are also increasing, So also will increase the requirements on measurement techniques for power quality indicator parameters.Measurement theory and algorithms of power quality indicator parameters in this study is of concern, is the most important. The research based on domestic and international power quality standards, the application of digital signal processing technology, combined with the research status of the power quality, The main contributions of this dissertation are listed as follows:1) On the basis of the original algorithm, using a new harmonic, This algorithm have a good Real-time according to the characteristics of the sine and cosine signals, the harmonic component to convert the DC component, and then through the low pass filter to estimate the initial phase angle and the RMS, through the reconstruction of the fundamental and integer harmonics subtracted from the original signal, the rest of the inter-harmonic RMS and the initial phase angle, which can be obtained. This algorithm is not only simple but also has well dynamic features.2) An improved algorithm is introduced on the basis of traditional single-phase voltage sag detecting one. By a new matrix, this algorithm obviously decreases the delay in traditional ways of constructing fictitious three phase systems, and this algorithm can also be used to evaluate characteristic parameters(such as, magnitude, duration and angel jump for voltage sag) in single phase systems.In this paper, the simulation shows the correctness and effectiveness of research related parameter estimation theory and algorithms, and provides effective tools for real-time monitoring and analysis of power quality.