Research On Virtual Power Quality Analysis System Based On FPGA

With the sci-tech progress and raising social productive forces，the application ofnonlinear devices in the power network is becoming a popularity, which raise the questionlike the deterioration of power quality. In the power network, many precision devices havehigh sensitivity to the decline of the power quality. However, the function of thetraditional power quality analyzer is simple. It is incapable of meeting the requirement ofthe real-time monitoring. Based on this problem, this paper put forward a developmentscheme of the virtual analyzer for the power quality based on the FPGA, which is thedesigning of high-speed acquisition sample board and the delivery of the collected data tothe PC machine for data processing. The brief explanation is as follows:In the hardware: based on the index of the power-quality analysis, this design adoptsthe modular designing concept and devises theprevia conditioning module, high speed ADacquisition module, DA trigger module, the module of frequency measurement, and highspeed USB2.0communication module. The FPGA acts as the main controller andimplement the time sequence of the whole system.In the software, this design includes the software of lower computer data acquisitioncard and PC machine software. The software of lower computer data acquisition card usesthe hardware descriptive language of the Verilog HDL to control the FPGA, which adoptsthe conception of modular programme and strengthens the readability and portability ofthe programme. The software of the host computer applies the CSharp language tocompile the man-machine interface and algorithm implementation. The algorithmimplementation refers to the analysis algorithm of the harmonic content, which isconstantly modified and finally successfully debugs algorithm software and theman-machine interface.Test results: This design tested the voltage, frequency and harmonic content, anddisplayed the test results on the display interface. Compared with standard values，thisvirtual analyzer for the power quality could implement the scheduled function.The virtual analyzer for the power quality could not only measure the voltage in thereal time, also analyze the high times of the harmonic content. This virtual analyzer has the advantages of good real-time performance, low cost, small volume and easy to carry,which is of high use value.