What is the voltage limit for emergency post-contingency situations?

The voltage limit for emergency post-contingency situations is set to 15 minutes. This duration provides operators with a critical timeframe to stabilize the grid and restore normal voltage levels following a disturbance.

In the transmission context, contingencies typically involve unexpected events like equipment failures or sudden load changes, which can lead to voltage fluctuations. The 15-minute limit reflects a balance between the need for a quick response to restore system reliability and the operational realities that allow for some short-term deviations in voltage parameters.

Restoring voltage within this timeframe helps to mitigate risks of cascading failures, ensuring the stability of the transmission network while allowing time for corrective actions to be planned and executed. This operational guideline is pivotal in maintaining grid reliability and preventing prolonged periods of voltage instability that could affect system performance or reliability.