Wide Area Monitoring and Control System: the Italian research and development

摘要

The development of Wide Area Measurement System (WAMS) technology is offering new and promising solutions for power system analysis, monitoring and control. The paper firstly reports the results of an Italian research program, aimed at promoting public research in the power system field, concerning WAMS technology and functionalities. Secondly, it part sketches the main specifications of a wide area measurement system currently under installation in the Italian power system. One of the key aspects of a WAMS project is the choice of the more effective system nodes to be monitored by Phasor Measurement Units (PMU). The subject of optimal PMU positioning is considered under different perspectives in the paper. In particular, as the number of available measurement devices does not allow complete system observability, interest is focussed on monitoring critical portions of the power system, i.e. areas subject to specific events (e.g. line trip with possible cascading) or phenomena (e.g. voltage collapse, oscillations) which may jeopardise system stability. After the PMU positioning a second very important aspect is the design of monitoring application functions to provide useful information to system operators. An algorithm for event identification is tested under complete and incomplete observability conditions. Additionally, the results on the following activities and analyses are reported in the paper: (a) an algorithm for on line identification of poorly damped oscillations; (b) tests about model identification for standard parametric identification algorithms; (c) a wavelet transform application to power system quantities for analysis and visualization of small-signal and transient phenomena. A simplified analysis tool for fast on line transient stability assessment and a proposal for an algorithm for network separation detection are also illustrated. Finally, the paper provides details on PMU characteristics, communication system, database and processing environment being used.