Design And Implementation Of Power Quality Monitoring And Management System Based On J2EE Framework

Power quality monitoring is a key part for the control of power quality, and is alsoa necessary condition to find power quality problems. The establishing of powerquality monitoring and management system (PQMMS) can not only get the historydata of power quality's parameter during the running of power system in detail, butalso monitor key power lines in real-time mode. Based on PQMMS, power qualityproblems is analyzed, and decision-support for improving the power quality of powergrid is provided. This thesis concerned the research and design of PQMMS s softwareplatform, and developed the power quality monitoring and management systemsoftware based on J2EE technology framework.This thesis researches the design and concrete realization of the software systemwhich provides services for the system with large network communication load, loadimbalance, and large capacity database system. The thesis's main innovations are asfollows:1. A mixed four-tier structure of software model for PQMMS was presented, wherethe application server's hybrid design enhances system's performance well.Meanwhile multiple design idea in software achieved the separation of data, businessand display well, and reduced the coupling among software and ensures the securityof data.2. Considering the work mode of database and computer, the thesis redesigned thedatabase's logical and physical structure. By using data cache table and data historicaltable in dynamic power quality running data's storage and management, unstableperformance and slow response of the database system with large capacity weresolved.3. The mode of main and sub ordinary communication server's design expanded thesystem's capability of communication and data processing, which solved the weak ofstandalone data-processing capabilities in large data collection system. The mode ofcommunication system was flexible, the communication system's maintenance wassample.The system has been running in shanghai power. The number of system'smonitoring device has been over 5,000.