What does "loop gain" refer to in a control system?

Loop gain is a critical concept in control systems that measures the overall amplification effect of a feedback control loop. It specifically refers to the product of the gain of all components present in the feedback loop, which includes the controller, sensors, and actuators. This calculation is vital because it helps determine the system's stability and performance. A higher loop gain indicates a more responsive system, as it signifies that the output will be significantly affected by changes in the input or disturbances.

Understanding the loop gain is essential when tuning control systems, as it directly relates to the system's ability to reduce error. If the loop gain is too high, it can lead to instability, whereas insufficient gain might result in sluggish system responses. Thus, calculating the loop gain serves as a fundamental aspect of assessing and enhancing control system performance.