Setpointin

Setpointin is a term used in control theory and process engineering to denote the practice and process of selecting and updating the setpoint—the target value that a closed-loop controller seeks to achieve. It can refer to both the initial choice of the target and subsequent adjustments as operating conditions change.

In a typical system, setpointin encompasses determining the nominal setpoint, scheduling time-varying setpoints (setpoint trajectories), ramping limits, deadbands, and constraints to balance performance, energy use, and safety. It involves decisions about how quickly setpoints can change, how to respond to disturbances, and how to prevent excessive actuator wear or instability.

Setpointin interacts with control algorithms such as PID controllers and model predictive control. A well-designed setpointing strategy considers disturbances, measurement noise, model accuracy, actuator limits, and the desired trade-offs between speed of response and overshoot. It may include both manual and automatic updates, as well as feedforward elements that anticipate known disturbances.

Applications span diverse fields, including temperature control in chemical processes, speed and position control in robotics, HVAC energy management, and automotive engine or powertrain control. The concept emphasizes planning and scheduling of target values rather than maintaining a fixed target in isolation.

History and terminology: The term is not universally standardized and is used in some academic or industry contexts to highlight proactive target-setting and trajectory planning within control systems.

Related terms include setpoint, control system, PID controllers, model predictive control, and trajectory planning.