A Design Of Remote Power Quality Measurement Terminal Based On DSP And CDMA Technology

With the development of society, people not only demand more electricity, but also require higher power quality. However, as power quality is characterized with randomness and non-reproducibility, traditional measurement equipments and testing methods find their way difficult to detect the grid failures effectively.Based on high cost performance embedded system platform, this paper proposes an efficient analysis terminal. It can achiveve real-time automatic measurements of power quality parameters online, and at the same time upload the data through a wireless data transmission, passing a long distance. The terminal uses AD7656, which is a 16-bit AD converter, to do signal sampling, while mainly uses TMS320C6713 floating-point DSP chip to complete data processing. The following methods are used to gain multiple power quality parameters. Interpolating windowed fast Fourier transform algorithm is used to analyze harmonic. Frequency is acquired by period-measurement method. Three-phase voltage unbalance and RMS are measured according to the national standards. The entire digital flicker measurement is achieved based on IEC 61000-4-15 standard. Besides, the system can capture transient, and then record the waveform. The terminal can also achieve long-distance and wireless transmission of the power quality data using LPC2214 which is based on ARM7TDMI core and MG801A-CDMA module. The data compression algorithm is also introduced to reduce the volume of data.Actual testing and simulation shows that the terminal can measure a variety of power quality parameters accurately, and transfer power quality data through extended Hualong protocol.