Question 399Motor Plants - Assistant Engineer

The correct answer is C) compensation. The governor characteristic used to maintain a set frequency on diesel engines driving alternators operating in parallel is known as compensation. This is because the governor system needs to compensate for changes in load in order to maintain the desired frequency. The compensation mechanism allows the governor to adjust the engine's fuel supply to keep the frequency constant, despite fluctuations in the electrical load. The other options, such as actuation, sensitivity, and promptness, while important governor characteristics, do not specifically describe the mechanism used to maintain frequency under varying load conditions.