Short Answer:

Sensitivity of a governor refers to its ability to respond to small changes in engine speed. A highly sensitive governor can detect minor speed variations and make precise adjustments to maintain the desired speed.

It ensures smooth and efficient engine operation by quickly correcting any deviations caused by load changes. Low sensitivity may result in delayed response, causing speed fluctuations and inefficient performance of the engine.

Detailed Explanation :

Sensitivity of Governor

The sensitivity of a governor is an important characteristic that determines how effectively it can control engine speed. It is defined as the change in the position of the governor sleeve or the control mechanism due to a small change in engine speed. In simpler terms, it measures how responsive the governor is to speed variations.

A governor with high sensitivity reacts to even small changes in speed, adjusting the fuel or steam supply accurately to bring the engine back to the desired speed. Conversely, a low sensitivity governor may require a larger change in speed to produce a noticeable adjustment, which can result in oscillations or delayed corrections.

Sensitivity depends on the design and type of governor. For example, centrifugal governors like Watt, Porter, Proell, and Hartnell have varying sensitivity levels based on the arrangement of balls, arms, and controlling springs. In spring-loaded governors, adjusting the spring stiffness can increase or decrease sensitivity. Shorter arms and lighter rotating masses generally increase sensitivity, while longer arms and heavier masses reduce it.

High sensitivity is desirable in engines that experience frequent load changes, such as generators, turbines, and industrial machinery. It ensures stable operation, prevents overspeeding, and maintains consistent output. However, extremely high sensitivity can make the governor prone to hunting, which is rapid oscillation around the desired speed. Therefore, a balance between sensitivity and stability is necessary for optimal performance.

In practice, sensitivity can be calculated by measuring the change in sleeve movement per unit change in engine speed. Engineers use this parameter to design and adjust governors to achieve precise control over engine speed while maintaining smooth operation. Sensitivity also influences other governor characteristics like speed regulation and stability. Properly designed sensitive governors improve engine efficiency, reduce fuel consumption, and prevent mechanical wear caused by sudden speed fluctuations.

Conclusion:

Sensitivity of a governor is its ability to respond to small changes in engine speed. A sensitive governor ensures accurate, smooth, and efficient speed control, making it essential for stable engine performance under varying loads.