Synchrophasor Initiative in India - erldc

SYNCHROPHASORS - INITIATIVE IN INDIA JUNE 20125.3 Detection of exceptional grid eventsSynchrophasor data has also been utilized to detect load throw off or generation loss in the gridas described ahead.5.3.1 Case Study-16: Partial disturbance due to voltage collapseA partial disturbance caused by voltage collapse occurred in 220 kV Punjab system on 20th July2011. The voltage at 220 kV Bhatinda and 220 kV Lehra Mohabbat was reported to have goneas low as 78 kV and 92kV respectively. The voltage profile of 400 kV Moga bus during the eventis shown in the below figure 59. It can be observed that there is around 4kV to 6kV dip involtages in all the three phases of 400kV system for around 9 seconds. The bus voltagerecovers after the cascade tripping.Figure 59: Dip in voltage at Moga during disturbance in Punjab systemFigure 60: Increase in frequency during the incident in Punjab due to loss of loadPOSOCO Page 73 of 143