Study Of The On-Line Power Quality Monitoring System Based On Virtual Instrument

In late years, power quality issues have captured considerable attention fromboth utility companies and their customers in many countries. It is the precondition of quality, safety, economy.To improve the electric power quality, a monitoring and analyzing system must be established.Traditional power quality monitoring system mainly based on hardware is bulky and crude, it has long adjusting period and high cost, and any change and update must change the hardware and the structure of the system, so it is unsuitable for modern instrument technology. ON-Line Power Quality monitoring system based on VI is developed using LabVIEW in this thesis.In the thesis firstly the theoretical background of power quality phenomena is introduced.Then, three transform-based methods, which are Fourier transform, short-time Fourier transform and wavelet transform, and their applications are described and discussed in detail.Secondly, this paper introduces the concept, structure and classification of virtual instruments, with a detailed description of virtual instruments software design tools—LabVIEW.Thirdly, introduces construction of ON-Line Power Quality monitoring system based on VI, including its basic architecture, hardware and software design;and points out the method of VI resolving scheme emphatically.It is the development trend of future instrument system by the use of software to bring about the hardware function, so it is the study emphasis of this paper also.At last, The concluding remarks discusses the prospects of the electric ON-Line Power Quality Monitoring System and summaries the deficiencies in the actually operating, it puts forward the possibly improvement of the thesis , too.