Study Of The Data Processing Modules And Algorithm In A Remote Power Quality Monitor

Power quality problem is becoming more serious because a large number of non-linear components are used in modern power systems.At the same time,the process of electric power marketing is speeding up rapidly.So both the power-supply side and the power-demand side are focusing on power quality problems.And as the rapid development of science and technology,new contents and new requests are added in power quality monitoring.In the paper,we firstly discuss the new research area of power quality monitoring and the developing trends ofpower quality monitoring devices at home and abroad.The research on power quality specification and arithmetic is also studied in the paper. Then we put forward a design of new power quality monitor using DSP+CPLD+ARM, we specially do some depth research on DSP part and CPLD part and also the arithmetic of every power quality specification.The system design based on DSP-TMS320C6713 produced by TI,as the main CPU, and CPLD-xc95144xl produced by Xlinx,as the main logical control device,to maximize the powerful computing capabilities of DSP.All of these created a good practical platform for the study following-up.We performed the arithmetic and the software design of the new power quality monitor based on national standards,which include voltage deviation,voltage unbalance,harmonics analysis and voltage flicker and so on.These indicators based of harmonics are calculated by traditional FFT algorithm, a FFT of sequence of complex numbers,which can reduce the computational complexity.The voltage flicker is measured by IEC model using digital filter methods. The measurement of inter-harmonics is by Burg method based on AR model.Finally, we achieve the software design on the platform of DSP+CPLD.