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A closed loop controller therefore has a feedback loop which ensures the controller exerts a control action to give a process output the same as the "reference input" or "set point". For this reason, closed loop controllers are also called feedback controllers. [3] The definition of a closed loop control system according to the British ...
Closed loop control [24]: 186 is a feedback based mechanism of motor control, where any act on the environment creates some sort of change that affects future performance through feedback. Closed loop motor control is best suited to continuously controlled actions, but does not work quickly enough for ballistic actions.
A control loop is the fundamental building block of control systems in general and industrial control systems in particular. It consists of the process sensor, the controller function, and the final control element (FCE) which controls the process necessary to automatically adjust the value of a measured process variable (PV) to equal the value of a desired set-point (SP).
In vector control, an AC induction or synchronous motor is controlled under all operating conditions like a separately excited DC motor. [21] That is, the AC motor behaves like a DC motor in which the field flux linkage and armature flux linkage created by the respective field and armature (or torque component) currents are orthogonally aligned such that, when torque is controlled, the field ...
The control action is the switching on/off of the boiler, but the controlled variable should be the building temperature, but is not because this is open-loop control of the boiler, which does not give closed-loop control of the temperature. In closed loop control, the control action from the controller is dependent on the process output.
A stepper, or stepping, motor is a synchronous, brushless, high pole count, polyphase motor. Control is usually, but not exclusively, done open loop, i.e., the rotor position is assumed to follow a controlled rotating field. Because of this, precise positioning with steppers is simpler and cheaper than closed loop controls.
The most common approach [3] makes the voltage V proportional to frequency f (so called V/f control, V/Hz control, Constant Volts/Hertz, CVH [3]). Advantage of the V/f variant is in keeping the magnetic flux inside the stator constant thus maintaining the motor performance across the range of speeds. A voltage boost at low frequencies is ...
Richard Schmidt (1975) proposed the schema theory for motor control, [6] suggesting in opposition to closed-loop theories, that a motor program containing general rules can be applied to different environmental or situational contexts via the involvement of open-loop control process and GMPs.