The Limitations of an Automatic Generation Control in Stabilizing Power System in the Event of Load Demand Increase

The main objective of an Automatic Generation Control (AGC) is to maintain the power system frequency to its nominal value following a disturbance. However, the control action of the AGC is dependable on the availability of spinning reserves. Due to deficiency generation reserve capacity, the system frequency stability can be compromised. The benefits and limitations of an automatic generation control are outlined in this paper. The AGC was developed and implemented on a modified IEEE 14 bus power system network using the DIgSILENT PowerFactory simulation tool. The results indicate that the AGC is only effective in the power system when there are enough spinning reserves. When the generation spinning reserves are depleted, the system frequency can not be maintained at its nominal state following load demand increase.