Regelgrootte

In control engineering isregelgrootte (regelgrootte) the quantity within a feedback loop that is measured and regulated. It corresponds to what in English is often called the process variable. The regelgrootte is the physical or process quantity whose value the system aims to keep close to a desired value.

The regelgrootte is compared with a setpoint (streefwaarde) to form an error signal. A controller processes this error and generates an actuation signal that drives an actuator, which in turn influences the process to bring the regelgrootte toward the setpoint. The process thus closes the feedback loop through sensors, controllers and actuators.

Regelgrootte can be a wide range of quantities, such as temperature, pressure, flow, speed, level, or chemical concentration. The exact choice depends on the application and the aim of regulation. The performance of regulation depends on the accuracy and speed of sensing, the dynamics of the process, and the tuning of the controller, often described by configurations such as P, PI, or PID control.

Disturbances, such as changes in load or ambient conditions, affect the regelgrootte. A well-designed control loop minimizes the deviation from the setpoint and attenuates the effect of disturbances, within the limits of the actuator and process dynamics. Understanding the regelgrootte and its interaction with sensor accuracy, actuator range, and setpoint specification is central to designing effective regulation systems.