Design And Implementation Of Power Quality Detecting System

With the rapid development of science and technology and the national economy, the demand for high-quality electric power in industrial production is growing. However, the use of modern electronic equipment and nonlinear load made the power increasingly serious polluted, power quality has been more and more concerned to the electricity sectors and its customers.Firstly, from the development process of power quality research, to the reason of paying attention to power quality and then to the standardization of the definition, classification, range and term for power quality. There are five prime indexes of power quality : voltage deviation, frequency deviation, harmonic content, voltage fluctuation and flicker, unbalanced three-phase voltage and current. This paper presented the concept of these five indexes, the criterion made by our country and introduced the correlative algorithms briefly.Then, the paper proposed the thought and the overall scheme of the real-time power quality monitoring and analyzing system based on distributed and designed the transformer substation power quality detecting system as client according to the scheme. Subsequently, the design and implement of hardware and software are mainly analyzed in this paper. With regard to the hardware design, computer system, electrical level modulating circuit and the data acquisition card are introduced. The function modules of the system based on the c language is discussed in the software design. The function modules of the system include the parameter-setting module, data-acquiring module, frequency module, effective value module, harmonic analyzing module, three-phase unbalance module, the voltage fluctuation and flicker measuring module, data storage module, real-time displaying module. The system can monitor electric power parameter in real time.Finally, this paper presents the results of primary test, the result proves that the system can meet the most requirement of designation for the power quality parameters monitoring system and establish the foundation for the implement of real-time powerquality monitoring and analyzing system based on distributed.