The Power Quality Expert System Construction And Research On Harmonic Management Methods

In recent years, with the expanding of power system capacity, a variety of distributedpower generation units gradually connect to the grid. At the same time, the increasing ofvarious nonlinear load and impact load results in bad power quality. While the sophisticatedelectronic equipment voltage disturbance sensitivity unabated, so that users are increasinglyhigh requirements of power quality. However, the existing power quality monitoring andmanagement technology had been difficult to meet the requirements of practical application.So this paper studied the power quality monitoring and management system based on expertsystems. This system can reduce the capacity and cost of power quality device effectively,and solve the field operation of power quality problems, such as control mainly withpersonnel operating experience which easy to cause blindness problem. The system achievesthe efficient power quality governance, intelligent control and optimization decisions.Firstly, the article summarizes the various power quality problems exist in the grid,describes the generation mechanism of various power quality problems; analyzes thecharacteristics of the main sources of pollution in the grid and established the mathematicalmodel; According to all kinds of power quality problems and mechanism of power grid, thepaper gives appropriate governance programs. All those related researches provide the baseknowledge foundation for the power quality construction of expert system.Secondly, the article focused on the harmonic problems in power quality and itssuppression technology, the analysis of the control method and design method of the activefilter and passive filter. This paper presented a new control method, which based on the directpower of active power filter harmonic detection. This algorithm had a higher precision andreliability than the conventional control method, and could effectively reduce the cost.Simulation had certificated the correctness and feasibility of the algorithm.Finally, the article analyzed the feasibility and advantages of expert system applicationin power quality monitoring and governance; analyzed and discussed the embodiment of thepower quality expert system from the knowledge base, a database, inference engine, theexplain mechanism and knowledge acquisition, and then established the harmonic source andharmonic management unit knowledge base, build the electric power harmonic monitoringand management expert system model.