Grid Standards Regulations, 2010-II: Categories of grid incidents, disturbances introduced

The CEA has now categorized all grid incidents and disturbances in the increasing order of their severity as a part of its Grid Standards Regulations 2010, released on September 3, 2010. Accordingly, there are two categories of grid incidents and five different categories of grid disturbances, the details of which have been given below:

 Categorization of grid incidents

 --Category GI-1

 Tripping of one or more power system elements of the grid like a generator, transmission line, transformer, shunt reactor, series capacitor and static VAR compensator, which requires re-scheduling of generation or load, without total loss of supply at a sub-station or loss of integrity of the grid at 220 kV (132 kV in the case of North-Eastern Region).

 --Category GI-2

 Tripping of one or more power system elements of the grid like a generator, transmission line, transformer, shunt reactor, series capacitor and Static VAR Compensator, which requires re-scheduling of generation or load, without total loss of supply at a sub-station or loss of integrity of the grid at 400 kV and above (220 kV and above in the case of NER).

 Categorization of grid disturbance

 --Category GD-1

 When less than 10% of the antecedent generation or load in a regional grid is lost.

 --Category GD-2

 When 10% to 20% of the antecedent generation or load in a regional grid is lost.

 --Category GD-3

 When 20% to 30% of the antecedent generation or load in a regional grid is lost.

 --Category GD-4

 When 30% to 40% of the antecedent generation or load in a regional grid is lost.

 --Category GD-5

 When 40% or more of the antecedent generation or load in a regional grid is lost.

 For the purpose of categorization of grid disturbances, percentage loss of generation or load, whichever is higher shall be considered.