engleski

WAMS in Croatian Power System

Wide Area Monitoring System (WAMS) project in Croatian power system has been realized in two phases. The first phase was as a pilot-project completed in 2003, with phasor measurement units (PMUs) installed in two adjacent 400 kV nodes. Its main task was monitoring of a very important transmission corridor, particularly with respect to line thermal limits and voltage stability. In the second phase that was realized during 2007 the system has been expanded to five PMUs installed in 400 kV nodes achieving a true system-wide monitoring scheme. New equipment has been also installed in the National Dispatching Centre in Zagreb and some new applications for system operation monitoring and analysis, such as power oscillation monitoring, have been added. Structure and capabilities of the present WAMS in Croatian power system at the present stage are briefly presented in the paper. Further discussion is focused on first experiences with the analysis of recordings from Croatian WAMS taken during large disturbances that had occurred in relatively remote parts of the UCTE interconnection. Two selected cases are discussed, the loss of a large generating unit in Spain, and the separation and resynchronisation of the power system of Greece. It is shown that valuable information can be extracted from time domain responses of bus frequencies and active power flows in transmission lines. Careful examination of WAMS recordings combined with understanding of physical phenomena in power systems can give a good starting point for evaluation of disturbances and interpretation of their possible causes. This approach could be of great assistance in analysis of contingencies in the system. Finally, further development of the WAMS project in Croatian power system is outlined and discussed.

WAMs; disturbance; power system analysis

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