Design And Implementation For Power Quality Monitoring In Local Supply Network

In recent years, power quality has gradually become an important concern. The extensive applications for power electronic apparatus and nonlinear equipment distort the waveforms of voltages and currents. As a result, power quality is going much worse. In addition, due to the improvement of industrial automatization, such parts of an apparatus as MPU and PLC are applied to industrial process controls, which are disturbed easily by stirs from power system. Therefore modern industry needs higher power quality than old one does. At the same time, with the rapid development of electric power industry, stabile power quality issues, such as voltage fluctuation and flicker, frequency fluctuation, harmonics, have increasingly captured considerable attention from utility companies and their customers. Transient power quality issues have been becoming extrusive, such as voltage well, voltage sag and voltage interruption, and bring customers amount of loss. Developing a system for Power Quality Monitoring(PQM) has been become the requirements of both the faculty and customers. It is necessary for novel techniques to meet the development.This development is confronting the industry with many new technical issues. Whereas formerly there was an interest in very few disturbance types, depending on the nature of the particular customer problem, now a wide range has to be handled, as presented above. Flexible PQ monitors need to be developed able to handle the full range of the above, instead of less versatile instruments dedicated to just flicker or harmonics for example. Monitor manufactures are taking advantage of developments in processing power to develop instruments with greater ability at lower cost and this trend looks to continue for some years. Monitors may be left in unprotected outdoor locations for many months and environmental specifications need to be made tighter.It is important to load data from them and manage the data for statistics and analysis in power quality problem.There are many ways for PQM and its data and this area also needs standardization. A methodology needs to be developed which is accurate enough to analyze and manage data from monitors but uses the minimum of monitors to reduce cost, communications, infrastructure requirements and data overload. Some of the issue which need addressing are(1) Which t approach for PQM data management should be determined?(2) Should the choice be entirely random or focused on sites with particular characteristic?(3) What should be the monitoring survey period?(4) What should be the most favorable data format for PQM?(5) How do handle versatile data for POM?This paper will summarise the key trends found for PQM and its data management and attempt to develop a system for local POM and data management which should been shared by both faculty and customers.