How does a closed-loop control system differ from an open-loop system?

How does a closed-loop control system differ from an open-loop system?

• A. Closed-loop uses feedback to adjust outputs; open-loop acts without feedback and relies on setpoints only
• B. Open-loop uses feedback; closed-loop does not rely on feedback
• C. Closed-loop ignores disturbances; open-loop automatically compensates
• D. They are identical in operation

Answer: (A)

Feedback control is what this item tests. In a closed-loop system, the actual output is measured with a sensor and fed back to the controller. The controller compares this measurement to the desired value (setpoint) and generates corrective actions to minimize the difference. This makes the system able to adjust in real time to disturbances, load changes, or model uncertainties, keeping the output close to the target. In contrast, an open-loop system applies a control signal based only on the input or setpoint, without measuring the result. Because it doesn't correct for what actually happens, it can’t automatically compensate for disturbances or changes in the system dynamics, so its performance hinges on assuming the process stays as expected. So the correct idea is that closed-loop uses feedback to adjust outputs, while open-loop operates without feedback and relies on setpoints. The other statements either imply feedback in the open-loop, claim automatic disturbance compensation for open-loop, or say the systems are identical, which does not reflect how feedback changes behavior.

Feedback control is what this item tests. In a closed-loop system, the actual output is measured with a sensor and fed back to the controller. The controller compares this measurement to the desired value (setpoint) and generates corrective actions to minimize the difference. This makes the system able to adjust in real time to disturbances, load changes, or model uncertainties, keeping the output close to the target.

In contrast, an open-loop system applies a control signal based only on the input or setpoint, without measuring the result. Because it doesn't correct for what actually happens, it can’t automatically compensate for disturbances or changes in the system dynamics, so its performance hinges on assuming the process stays as expected.

So the correct idea is that closed-loop uses feedback to adjust outputs, while open-loop operates without feedback and relies on setpoints. The other statements either imply feedback in the open-loop, claim automatic disturbance compensation for open-loop, or say the systems are identical, which does not reflect how feedback changes behavior.