Which method is commonly used for tuning PID controllers?

The Ziegler-Nichols method is a widely recognized approach for tuning PID controllers. This method involves determining the system's ultimate gain and the oscillation period of the system when subjected to feedback with proportional gain only. By carefully adjusting these parameters, you can calculate specific PID controller settings that are expected to yield good performance for the control system.

The advantage of using the Ziegler-Nichols method lies in its simplicity and its ability to produce a good balance between responsiveness and stability, often resulting in a controller that can handle disturbances and maintain the desired output effectively. The method is particularly valuable for systems where a comprehensive model is either difficult to obtain or not practical to use, allowing for empirical tuning based on the observed system behavior.

Overall, the prevalence of the Ziegler-Nichols method in industry stems from its effectiveness and the relative ease with which it can be applied, making it a go-to choice for many control engineers.