On which principle does a PID controller operate?

A PID controller operates on the principles of Proportional, Integral, and Derivative control actions. This approach enables the system to adjust its output based on three distinct aspects of the error signal, which is the difference between a desired setpoint and the measured process variable.

Proportional control responds to the current error, providing an output that is proportional to the error size. This allows the controller to take immediate action to reduce the error.

The Integral action accumulates the error over time, addressing any persistent offset that may exist in the system. By integrating the error over time, the controller can adjust its output to eliminate steady-state error.

Derivative control anticipates future error by assessing the rate of change of the error. This predictive capability helps to dampen the system's response and mitigate overshooting, allowing for a more stable control.

Together, these three components make the PID controller a robust and versatile tool for managing dynamic systems, providing stable and responsive control across various applications in engineering and robotics.