Design Of Power System Harmonic Detection And Analysis System Based On Embedded System

In recent years,power electronic technology is developing rapidly,Meanwhile,nonlinear loads are used universally in the power system which cause harmonic increase and power quality reduction.Harmonic can cause serious economic losses.To curb the power quality deterioration,strengthen the power quality detection is particularly important.In this paper,with the reference of domestic and foreign instrument cases,a harmonic detection and analysis system is designed and implemented,in order to meet the higher requirements of the harmonic detection process.The paper completes the following tasks:1.Research on power harmonic detection principle,determine the overall structure of the system combined with the experience of foreign instrument development.The hardware part includes analog processing circuit,digital control circuit;the software includes system porting,driver design,harmonic detection algorithm and application interface development2.The embedded development environment based on Android system is established,and the system image file is compiled and transplanted with the target board.In order to improve the system accuracy,in the ARM processor platform on the expansion of AD conversion chip.Receive data using two level buffer structure,complete the sampling data receiving,unpacking,framing the task.The drive allows the kernel to maintain a smaller size and flexible operation program dynamic loading method,improve the CPU resources and memory utilization.3.This paper studies a variety of harmonic detection algorithms,and analyzes the advantages and disadvantages of various harmonic detection algorithms.In this paper,the windowed interpolation FFT algorithm is used to detect power harmonics.The appropriate window function can suppress the long range spectrum leakage.After processing the windowed FFT signal,spectral line interpolation in frequency domain can be used to suppress short range spectrum leakage.The windowed interpolation algorithm can improve the accuracy of harmonic detection.4.The application program based on Android system is designed,and the driver can be operate by writing the local method.According to the principle of harmonic detection,the windowed FFT harmonic detection program is written,in order to further improve the detection accuracy,a double line interpolation algorithm is achieved,which can truly reflect the harmonic information.The application software interface can display of the test results.5.Based on the wide application of wireless communication technology in engineering,the wireless data transmission function based on Bluetooth module is designed,and the test results are transmitted to remote Android devicesFinally,through the experimental test,the design of the power grid harmonic detection and analysis system not only has strong data processing ability,good human-computer interaction,high detection accuracy,but also can carry out remote data transmission,to meet the requirements of harmonic detection...