In relation to voltage limits during pre-contingency, what is the maximum time allowed for high voltage situations?

In the context of voltage limits during pre-contingency analysis, the maximum time allowed for high voltage situations is indeed 15 minutes. This timeframe is established to ensure that the transmission system remains stable and does not experience adverse effects due to prolonged high voltage conditions. High voltage situations can lead to equipment damage, insulation failures, and overall system reliability issues.

By allowing a maximum of 15 minutes for these high voltage scenarios, operators have a window to implement corrective actions, manage the grid effectively, and return the system to acceptable voltage levels without compromising safety and reliability. This guideline aligns with industry standards aimed at maintaining system integrity while addressing potential disturbances.

The other options of 5, 10, and 30 minutes do not provide a suitable balance between operational flexibility and the need to ensure system stability, hence 15 minutes is set as the appropriate duration.