Research On Power Quality Analyzer Based On DSP+CPLD

At present,as a most direct energy commodity,electricity has differences in quality.Therefore,the detection and analysis of power quality data is particularly important.In this article,we begin with the theory of power quality,and design a power quality analyzer prototype.Firstly,we described the theory of power quality,and the main factors of harmonic and influence of measurement error are analyzed.In the analysis of the principle of signal harmonic,the use of fast Fourier transform(FFT)can greatly reduce the analysis time and improve the efficiency of analysis,and put forward the operation of the relevant issues and solutions.Frequency measurement is the key point of this article,for its design frequency real-time tracking sampling function can greatly reduce the error.Measurement voltage flicker is difficult to achieve,combined with IEC on the measurement of voltage flicker requirements and reference program,which can simplify the measurement model to achieve the detection of flicker visual perception.Secondly,based on this theory,we designed the power quality analyzer prototype.The system uses the power quality acquisition board to collect 6 analog signals,and then converts to digital signal by the AD conversion module,controls the digital signal to input to the DSP processor.The DSP processor can rapidly analyze data by using FFT algorithm,and finally the data displayed through the CPLD on the LCD,which can reduce the burden on the DSP chip.Following the structural design,the software can implement each function of the program by interrupt processing,and the system flow diagram is designed with the hardware chip design program.We also introduced the software to achieve frequency synchronization,harmonic analysis of the FFT operation,liquid crystal display software programming problems.Afterwards,combined with software analysis and debuging,we tested the hardware.Finally,the results show that the experimental device can display the waveform,voltage RMS,current RMS,spectrum and other functions.Finally,this article summarizes the deficiencies encountered in the research work and prospects for power quality.