Evaluating frequency quality of Nordic system using PMU data

This paper focuses on analysing frequency quality of Nordic power system using measurements from phasor measurement units (PMU). The PMU data of one year long period is used which has very high time resolution (20 ms per sample) and is able to provide detailed information in evaluating frequency quality and its correlation with time. The results show that the frequency quality of the Nordic power system is not satisfactory according to the suggested requirements. The electricity market operation is found to be one of the major reasons behind. Based on the results, discussion of frequency control for future power system is made where several new technologies of interests are suggested to be investigated.