PStatistical Analysis on Inter-area Oscillations
Figure 1 shows the oscillation occurrence distribution of EI through 2013 to 2015. In 2013, most oscillations were detected in January and February for EI system. However, in 2014 and 2015, majority oscillations occurred between July and November. More oscillations occurred from 8:00am to 12:00pm (UTC time) in all three years. Figure. 2 shows the dominant frequency distribution of inter-area oscillations in EI. The majority oscillation frequencies of each hour are similarly around 0.2Hz (dominant mode 1). Minimal difference can be observed in the dominant frequency distribution of inter-area oscillations in different hours.
Fig. 1. Inter-area oscillation occurrence distribution of EI
Fig. 2. Dominant frequency distribution of inter-area oscillations in EI