What is meant by generator droop?

Generator droop refers to the characteristic behavior of a generator in response to changes in load, specifically how it decreases its operational frequency as the load increases. This concept is crucial in maintaining system stability and ensuring that frequency remains within acceptable margins under varying load conditions.

When a generator is subjected to an increase in load, it cannot maintain its original frequency if it does not have the ability to adjust its output power correspondingly. The "droop" refers to the relationship between the generator's output frequency and the load it is supplying. A generator configured with droop response will lower its frequency slightly as the load demand increases, allowing other generators within the same grid or network to compensate by adjusting their outputs. This coordinated response is key to maintaining overall frequency stability across the power system, particularly during events that affect generation and load balance.

The other options do not correctly describe the concept of generator droop. Increasing power output is not a characteristic of droop, but rather reflects a generator's capability; speed fluctuations relate more to transient disturbances than droop; and maintaining a constant frequency regardless of load directly contradicts the principle of droop behavior. Understanding droop is essential for effective power system operation and coordination among multiple generators within a grid.