A Distributed Harmonic Online Detection System Based On Internet Of Building Equipment

The harmonic sources within the building get more and more in recent years, with the rapid development of modern science and technology such as information industry and modern power electronic technique. There are a lot of harmonics in the grid, and the harm caused by it to the civil power distribution systems and electrical equipment is serious day by day. The research on harmonic detection system is in progress so as to reduce the harmonic harm. Many scholars and companies have devoted to the research on harmonic detection system in order to reduce the harmonic harm.Harmonic detection system possesses the capable of monitoring electrical equipment and distribution circuits harmonic. It is divided into off-line monitoring and on-line monitoring system, which is based on whether the system is a real-time one. The off-line testing methods can only test the unilateral harmonic data, which can be used for reference in some degree, but long-term and real-time harmonic data of a variety of electrical equipment and distribution lines in building cannot be obtained. The on-line monitoring system can detect the harmonic quickly and accurately. But there are some slip problems to be solved such as the high cost of the installation and the online monitoring system is the high cost of devices and not suitable for monitoring multi-device or power distribution branches.The purpose of this project is to study a distributed harmonic detection system, which used to detect harmonic. FFT-based theory and the Internet of Things technology are adopted in harmonic analysis, while harmonic on-line detection is realized.Firstly, the research background and the domestic and overseas development states were summarized in the paper, and further analysis was made on some key problems needing to be solved. Then the important background knowledge used in the subject was introduced simply, including the Internet of Things technology and the selection of wired and wireless networks. According to the harmonic detection function to be achieved in the system, the paper made a deep analysis on the overall scheme and technology research. The hardware and software design of the Internet of Things nodes and the harmonic detection terminal module were introduced emphatically.Secondly, a detailed representation of the server software functions was given. The Browser/Server architecture design was used in the server software. The technical architecture to the server software was divided into four layers, which included the data collection layer, the data layer, the business layer and the presentation layer. Each layer was described in detail. An experimental platform was built according to the functions and system design scheme of the distributed harmonic detection system. Then the analysis accuracy was verified and the experimental results and functional verification were displayed.Finally, summarize the main research work and the existence of inadequacies, and future research and application prospect prospected.