Figure 1.1 Stages of power system frequency response after a disturbance ........................................................ 19 Figure 1.2 Frequency response during 12 March 2014 event ............................................................................... 20 Figure 1.3 Frequency response during 23 April 2018 event .................................................................................. 21 Figure 1.4 Frequency response during 28 May 2020 event ...............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Frequency Drop .................................................................................................... 76 Figure 6.6 Power number during different grid events in India ............................................................................ 77 Figure 7.1 Flow chart for online inertia estimation ............................................................................................... 81 Figure 7.2 Online inertia monitoring in NRLDC EMS ............................................................................................. 82 Figure 7.3 Online inertia monitoring in WRLDC EMS ............................................................................................ 82 Figure 7.4 Online Kinetic energy monitoring in SRLDC EMS .................................................................................. 82 Figure 7.5 Online inertia monitoring in ERLDC EMS .............................................................................................. 82 Figure 7.6 Online inertia monitoring in NERLDC EMS ........................................................................................... 83 Figure 7.7 Online inertia monitoring for All India grid in NLDC EMS ..................................................................... 83 Figure 7.8 Sample daily kinetic energy curve for All Indian Grid ........................................................................... 84 Figure 7.9 Sample daily kinetic energy curve for NR ............................................................................................. 84