What is the main function of Automatic Generation Control (AGC) in terms of NERC compliance?

The main function of Automatic Generation Control (AGC) is to maintain system frequency and balance. AGC plays a crucial role in the electric power grid by automatically adjusting the output of multiple generators to ensure that electricity supply matches the demand in real-time. This is vital for maintaining the frequency of the electric system, which is typically targeted at 60 Hz in North America.

When there is an imbalance between generation and load, AGC quickly responds by either increasing or decreasing the output of generators, thereby ensuring that the system frequency remains stable and that the overall power balance is sustained. This functionality is particularly important for compliance with NERC standards, which aim to ensure the reliability and security of the bulk power system.

While operating generators at full capacity and reducing operational costs are important operational objectives, they are not the primary focus of AGC. Similarly, isolating failed units is a critical function related to system reliability, but it falls outside the specific purview of AGC, which is more focused on real-time management of generation output to balance load and maintain frequency.