Data Acquisition And Processing Of High Speed Power Analyzer

When there is a problem with the power signal,it is easy to cause a very large safety accident.How to comprehensively detect the quality of the power signal while ensuring the accuracy of the detection is always a major problem in the quality detection of the power signal.With the rapid development of technology,electric vehicles and solar generator and wind turbines are well known to the public and gradually enter people’s lives.The number of power signals,harmonics and power parameters that need to be measured are increasing.The number of channels,sampling rate and measurement accuracy of power analyzers for power signal detection instruments face higher challenge,it is of great significance to develop a multi-channel,high sampling rate,high-precision power analyzer to protect people’s lives and property.Based on the power analyzer project,this paper designs and implements the highspeed data acquisition module of the platform.At the same time,it proposes and designs a multi-channel real-time harmonic analysis method,which mainly includes the following contents:1.According to the design indicators of high-speed power analyzer,the feasibility analysis of the high-speed power analyzer is carried out from the system perspective,and the feasibility of the data acquisition module and the real-time harmonic analysis module is analyzed according to the overall architecture of the system.And then according to the design indicators and analysis results,I select the core device ADC and FPGA of the project.Finally the design of the data acquisition module and real-time harmonic analysis module is proposed according to the actual selection device.2.Design and implement dual-channel high speed data acquisition module.Realize the synchronous acquisition of the dual-channel 12-bit high-speed 100 MSPS sampling rate for voltage signal.For the problem of the different transmission rate of signal and the control signal between the acquisition board and the data processing board,two different channel transmission methods are designed,that is,respectively,using SerDes and UART realize the transmission of high-speed data and control signals.In addition,in order to realize the automatic configuration function of the calibration data,this method saves the calibration data in the FLASH integrated which is in the acquisition board,and the calibration data can be automatically read when the instrument is turned on.3.Design and implement three-channel real-time harmonic analysis module.Realtime harmonic analysis of three channels is realized,and the harmonic measurement accuracy reaches 0.5%.The design takes 1024 points per cycle per cycle,and a total of 8 cycles are used for FFT operation.In order to improve the accuracy of the harmonic analysis,the accuracy of the frequency multiplier is improved,and the signal to be measured is synchronously extracted with the frequency multiplied signal,which reduces the truncation error of the FFT analysis.Then the obtained 8192 data points are passed through the FPGA FFT IP core and it implements the FFT analysis function.Finally it sends the result to the host computer for display.After testing,the data acquisition module and real-time harmonic analysis module of the power analyzer can meet the indicators.