What happens to generators when synchronizing power is lost?

When synchronizing power is lost, generators experience a significant loss of stability, which often leads them to trip offline. This loss of synchronization typically occurs when there is a significant frequency or voltage deviation from the expected operating conditions that the generator is designed to handle.

Generators are equipped with protective relays that monitor various parameters such as frequency and voltage. When these parameters go beyond preset limits during a loss of synchronism, the protective relays activate, leading to the generator being disconnected from the grid to prevent potential damage to equipment and maintain system stability. This is a critical safety mechanism to ensure that a generator does not operate under conditions that could result in mechanical stress or other operational failures.

In contrast, the other options do not accurately reflect the typical response of generators under these conditions. They cannot simply continue to operate normally as that would put the unit and potentially the entire grid at risk. Increasing output would not be a viable option because the generator would not have the necessary electrical synchronism to do so safely. Switching to backup power is also not applicable in this context, as the generator would be the primary power source and would not have an alternative source to seamlessly transition to under these circumstances.