Analysis And Detection Of Time Frequency In The Grid Harmonics Process

In many of the indicators as a measure of power quality, grid harmonics can be said to be one of the most important indicators. In a process of operation of the system, which generates a harmonic component, for example, different steady and unsteady mutation signal in the grid which can be through current, voltage reflected. By measuring and processing the harmonic value, as the orientation of the development of the power system is essential. In recent years, due to a large number of different types of electronic equipment is generally people use, Caused the utility grid harmonics are increasingly powerful, therefore the cause of the accident and failure are endless. Therefore to avoid damage generated by harmonic and further improved the quality of the electricity. Whether it is the power grid or other electronic devices, real-time measurement and treatment through its harmonic components, this is indispensable for the understanding of the operation of the electric power system environment.This article focuses on the harmonic measurement and treatment methods and achieved by using MATLAB software simulation environment analysis and processing, focuses on the two main harmonic approach, one is wavelet transform, and the other is the Fourier transform, finally elaborate study results. The main content of this article contains:A detailed overview of the theoretical knowledge grid harmonic, and details of the important methods of measurement and treatment of harmonic, Then a brief overview of the basic harmonic detection method, mainly to discuss a Fourier transform and wavelet transform. Then discussed the time-frequency analysis of based on the time-frequency analysis of the meaning and purpose. Then, the establishment of various types of network harmonic signal model, Harmonic model also were windowed Fourier analysis and wavelet analysis, By analyzing the changes summarized Fourier and wavelet transform their application of harmonic type. Discuss their respective advantages and disadvantages. Harmonic changes to process real-time tracking and detection, very intuitive harmonic observed the trend.Then developed harmonic detection system. The first step to determine the overall configuration of the system, the second step within the system hardware design, including the composition of the data acquisition card, drivers, etc. The third step is based on the foregoing analysis of the system software algorithm design. This paper analyzes detection system verification, validation can be seen through the actual article is designed harmonic detection systems can be more accurately detect harmonic.