Stilstyring

Stilstyring refers to the process of maintaining a system at a desired steady-state value, or setpoint, through autonomous regulation. In control theory, stilstyring is achieved by a feedback loop that compares the measured output with the desired setpoint and adjusts inputs accordingly. The goal is to reject disturbances, compensate for model inaccuracies, and minimize steady-state error while ensuring stability.

Common elements of stilstyring include a sensor that measures the process variable, an actuator that applies the control input, and a controller that computes the necessary adjustments. Controllers are often designed using algorithms such as PID, PI, or more advanced methods, and may include feedforward components to counter known disturbances. Proper tuning of control parameters is essential to balance responsiveness, overshoot, and robustness.

Applications of stilstyring are broad and include manufacturing processes, energy systems, building automation, and transportation. Systems may operate in continuous-time or discrete-time domains, and practical implementations must handle measurement noise, time delays, nonlinearities, and changing operating conditions.

Stilstyring is distinguished from other control modes by its emphasis on maintaining a fixed operating point rather than tracking rapid trajectories. However, many real-world systems combine steady-state regulation with dynamic control to handle transients and shifts in conditions.

Terminology varies by language; in Danish and Norwegian technical literature the term describes steady-state regulation, while in English literature it is often referred to as steady-state control or setpoint regulation.