Research Of Three-phase Power Quality Monitoring System Based On LabVIEW

With the increase in non-linear and shock loads, power quality problems become increasingly prominent. Currently in domestic the statistical voltmeter monitor is widely used in monitoring voltage quality, this voltmeter is only to monitoring voltage passing rate, at the same time, the harmonics with voltage fluctuation and flicker measurement is needed to adopt portable measuring instruments. Site survey measurement and the measured data through statistical analysis, then the quality level is achieved. This kind of power quality monitoring instruments has the obvious limitation, such as manifested in poor real-time, less monitoring indicators, heavy workload, measurement error, and low efficiency etc. In order to improve the limitations of existing power quality monitoring, the industry urgently calls for a kind of electrical energy monitoring devices which could monitor power quality in real time, more accurate, and comprehensive.In this article according to the national power quality indicator analyzes the power quality measurement principle, an analysis of power quality of the mathematical model is established.The virtual instrument technology is used to on-line monitoring of power quality in power system, building the three-phase power quality monitoring system based on LabVIEW and proposed an effective solution to resolve energy monitoring not continuous, real-time poor, big error of multi-parameter measurement etc.To ensure real-time acquisition of three-phase electricity, the single-chip computer data acquisition circuit, signal conditioning circuit, upper and lower computer interface circuit and other auxiliary circuits ect hardware is designed and produced.With the LabVIEW and single chip mixed programming method, system can comput and analysis the quality indicators of voltage deviation, frequency deviation, fluctuation and flicker after signal acquisition to complete system software design. The final results is output onto the host computer panel to realize the automatic monitoring of power quality indicators. By the comparative experiment for part of power indicator between this system and the Power Q-type hand-held Power Quality Analyzer, the results show that this system can measure the power quality accurately, and with some advantages such as precision, real-time performance, intuitive interface etc. This measurement process can overcome the problems such as cumbersome, measurement limitation, manual calculation and hard to function expansion, it lays the foundation for realization network management of power quality.