13.9.2016 12:40
Current News, Power System

Report on frequency quality for 2015

Fingrid has published a report on frequency quality of the Nordic power system for year 2015. Frequency quality statistics are presented for previous years as well.
The report contains an analysis of the amount and duration of frequency deviations where frequency has deviated from the standard frequency range (49,9 - 50,1 Hz). The amount of a low frequency oscillation visible in the Nordic power system and its effect on frequency quality has been analyzed as well. In addition, the report includes various other frequency quality indices and a summary of the largest frequency deviations during 2015.
During 2015 frequency quality was approximately on the same level as the previous years. Frequency quality has decreased from the beginning of the 21st century to the beginning of the 2010s. During the 2010s the decrease in frequency quality has stopped and in terms of frequency quality, the year 2015 was better compared to the beginning of the 2010s.
The report can be accessed here. Fingrid has also published the frequency measurement data used in the analysis and continues to publish more data periodically. The data can be accessed here.
The balance between power consumption and production can be observed in power system frequency. If consumption exceeds production, frequency begins to decrease. Vice versa, if production exceeds consumption, frequency begins to increase. During normal operation, frequency in the Nordic power system is allowed to fluctuate between 49.9 and 50.1 Hz. During disturbances, like a loss of a large generator, frequency can momentarily deviate by several hundreds of millihertz from the standard frequency range (49.9 – 50.1 Hz). See the Reserves video on Fingrid's YouTube channel for more information on the maintenance of power system frequency.
Further information:
Mikko Kuivaniemi, tel. +358 30 395 5188
Minna Laasonen, tel. +358 30 395 5132