Research On Power Quality Monitoring System Based On FPGA

Nowadays a great deal of power electronic devices have acess to power network, which give rise to many kinds of problems about power quality.And these problems not only threaten the security and stability of electric system, but also the users. So it is very meaningful to design a new type of real-time power quality monitoring system.This paper firstly analyses research on the field of pwer quality monitoring system home and abroad and the signification of developing a new type one.On basic of analysis of parametres of power quality index and testing pricipals and algorithm, this paper develops a real-time power quality monitoring system based on FPGA according to six national standards.By making use of powerful caculation of FPGA, it fulfills real-time monitoring ,recording and analysis of a series of parameters of power quality,including voltage and current effective value of AC,frequency, harmonics of voltage and current,wattful power and wattless power.The system can be divided into two parts: upper computer and lower computer. The lower computer ueses FPGA-EP1C20F3247 as the hardware core controlment device. In this part, the system includes several hardware circuits, such as signal handling unit,data generating unit, data management unit and comunication unit. The units can generate the voltage and current signals from power grid through six channels, and then process and analyse them. About the software designation the lower computer accesses the uC/OS system upon which the author develops data collecting module, data analysis module and cmmunication driver program.The software on the upper computer are more powerful. In the software development environment, LabwindowsCVI, it designs three phase real-time analysis HIM with 6 channels which include receiving data module, data analysis module and data displaying module.The last part is test of power quality monitoring system,the hardware circuit combined with upper computer. These tests are made, including frequency and THD measurement, tests of signal processing circuit and communication function and data compressing. The results show that the measurements are not beyond the error limit, and the system can realize the fuction desired.