Abstract
We are in the low-voltage distribution cabinet design, it must take into account the safety performance, power distribution reliability, power utilization and other factors, so that the design of power distribution cabinet to save energy. Therefore, we can choose in the main distribution cabinets and distribution boards installed EP device, then will be able to make, whether caused by external interference or mutual interference caused by harmonics and surge voltage to enter the equipment and eliminate it before it is absorbed.
we in this paper focused on measurement and harmonic content of governance in order to get a clear understanding of harmonic operation of equipment, such as the impact of the installation in distribution cabinets eliminated, reduced harmonic device, so that low-voltage design a more perfect distribution cabinets.
First of all, the paper provides an overview of the harmonic background and current development trends. Fourier transform of the basic theory, practical application of the basic form and should be paid attention to the issues in detail, the traditional windowed DFT-based harmonic detection of the error causes and ways to reduce the error analysis, and introduced a variety of cosine window function, and a brief analysis of the spectrum of several common methods of correction. The simulation examples show that the time window to select the appropriate length of sampling points and the corresponding window function, the algorithm can be accurately compared to measure the harmonics and the parameters of inter-harmonic