What happens to system frequency when more load is added than generation capability during system restoration?

When more load is added than the generation capability during system restoration, the system frequency will drop. This occurs because frequency is a direct indication of the balance between power generation and consumption. In an electrical grid, when the load exceeds what the generators can supply, there is a deficit of power.

As a result, the demand for electricity pulls the operating frequency down. This drop in frequency signals operators and automated systems to either reduce the load, increase generation, or stabilize the grid to restore balance. Essentially, if more consumption occurs than what can be produced, the motors and generators in the system cannot sustain the frequency level, leading to a decrease in overall system frequency.

The other options do not accurately represent the physics of frequency in power systems under these conditions. For instance, system frequency increasing would imply that there is an overgeneration situation, not the case here. Similarly, simply stating that system generation increases does not address the immediate effect of the imbalance, and suggesting that system inertia will maintain frequency is misleading, as while inertia does provide some short-term stability, it cannot prevent a frequency drop when the load continuously exceeds generation.