The Research And Design Of Power System Harmonic Detective System Based On FPGA

With the rapid development of science and technology, more and more power electronic equipment used in the power system, which brought about the growing problem of harmonic pollution can't be ignored. To this end, it is necessary to conduct in-depth study of harmonic to reduce the harm of the harmonic caused, and the harmonic detection is an important branch of harmonic research and a necessary prerequisite with great significance. In this paper, based on Hilbert-Huang transform (HHT), conduct in-depth study and simulation on the harmonic detection algorithm, and on this basis, design the harmonic detection system.In the signal de-noising algorithm, paper analyzes and compares two kinds of de-noising algorithm which are the wavelet transform and fractal dimension theory, combined with their respective advantages, propose a theory based on fractal dimension of the adaptive threshold wavelet de-noising algorithm, and the simulation demonstrated the feasibility of the algorithm. In the harmonic detection algorithm, paper first on the fast Fourier algorithm (FFT) simulation analysis, found it difficult to use the algorithm on the harmonic detection of non-stationary signal, and then paper using the Hilbert-Huang (HHT) transformation, this algorithm can detect non-stationary signals, in the simulation process, found its shortcomings, and make improvements, through the simulation, demonstrate its effectiveness.Paper designed harmonic detection system. FPGA is used in system hardware as the core processing chip of the process of signal acquisition, after the harmonic signal sampled from the system, converted to the digital signal through the A/D converter sent to the FPGA, the FPGA is responsible for the chip control of A/D converter, and data storage, and data via the serial communication interface sent to the host computer. System software is divided into lower computer software and host computer software, the lower computer software using Quartus II platform to design, Using VHDL language programming of the functions of the FPGA; the host computer software using MATLAB GUI to design interface, and using MATLAB programming language to complete the functions as data reception, the draw of the waveform, the signal de-noising and harmonic detection, and finally calculate the instantaneous parameters of each harmonic.Finally, the designed harmonic detection system was tested in paper. The results show that the system can meet the requirements of harmonic detection, with a certain practicality.