落幕未终场
Abstract
Quality of electric energy supply by means of the public power grid user end of the AC electric energy quality. The ideal state of public power grid should be at a constant frequency, the standard sine wave and rated voltage of power supply. At the same time, in a three-phase system, each phase voltage and current amplitude should be equal, symmetry and phase difference of 120 degrees. But due to the system of generators, transformers and lines and other equipment, nonlinear or asymmetric load varied, and the control measures are not perfect and the operation, the external interference and all kinds of fault and other reasons, this ideal state does not exist. Therefore, to generate grid power equipment and power supply link in the various problems, also produced the concepts of power quality.
Before the reform and opening up, China's industrial level is more backward, manufacturing process relatively rough, high, fine, sharp aspects of advanced manufacturing industry is lacking, therefore, the influence and harm of harmonic cause is not obvious, and the electric energy quality problems do not mention to the schedule. It is generally believed that, as long as the frequency of normal as well as guaranteeing the supply voltage in a certain range, to ensure the quality of electric energy. In addition to our country electric power system from the point of supply demand relations, before 80 time in planning and shortage economy period, there is no electricity available to users is the main problem, natural" power quality” the problem is mentioned.
With the development of the national economy, the progress of science and technology and the production process is highly automated, of various nonlinear network load increasing; a variety of complex, sophisticated, sensitive to electric energy quality of power equipment are more and more. With the popularization of computer technology, based on computer system control device and electronic device not only for the quality of power supply is very sensitive, and increase the power quality deterioration.
This paper describes the problem of electric energy quality, monitoring contents, monitoring and its governance, through to the real monitoring system analysis to draw a final conclusion.
Keyword: Quality of electric energy, Harmonic, Power quality monitoring system, Management
