Design Of Power Quality Monitoring Experiment Platform Based On LabVIEW

With the rapid development of economic and the continuous progress of technology, electrical equipments with non-linear characteristics increase dramatically which is harmful to the power system. The quality of power network is getting worse which directly threatens to the safe operation of the electrical equipments. Therefore, in order to protect the quality of power supply,it is important to monitor and analyze power quality parameters accurately,efficiently and quicklyA power quality platform of experiment and monitor are designed based on LabVIEW software and the data acquisition card of PCI-6024 E. It can be applied to monitor power quality parameters of the 220 V / 380 V low voltage power network and protect the safety of power grids and electrical equipments.It can also be used for teaching in some university laboratories.Firstly,this paper introduces the research background of power quality, and describes the current status and the future direction of power quality monitoring equipment.Secondly, some measurement algorithms of power quality are studied in this paper. Then combined with virtual instrument technology, a monitoring experimental platform of power quality based on LabVIEW is designed. It includes hardware and software systems. The hardware system consists of mutual inductor, signal conditioning circuits, BNC-2120 terminal block and PCI-6024 E data acquisition card. Software system contains five power quality indicator monitoring modules, basic parameters module, power module,three-phase unbalance module, voltage fluctuation and flicker module and power harmonic module. It can realize the function of real-time monitoring of power quality indicators, such as, three-phase current, three-phase voltage,power, three-phase voltage unbalance, total harmonic distortion, instantaneous flicker sensation level and short time flicker values.Finally,the platform is applied to measure the performance of an actualsystem. The SCR rectifier device of DC motor speed regulating system was used as the system under test. Through the comparison and analysis of the experimental results, it is proved that the platform has a fast calculation speed and it can running steady for a long time. So, the platform in this paper has a practical value.