Open Loop Control System
An open loop control system is a system that does not have feedback, the control action is independent of the output. In this system, the output is not compared with the input. Therefore this system is also known as the Non-Feedback System.
FIG. BLOCK DIAGRAM OF OPEN LOOP CONTROL SYSTEM
Closed-Loop Control System
A closed-loop control system is a system that has feedback, the control action depends upon output. In this system, the output is compared with the input, and an error signal (if any) is produced. Therefore this system is also known as the Feedback System.
FIG. BLOCK DIAGRAM OF CLOSED-LOOP CONTROL SYSTEM
Difference between Open-Loop Control Systems and closed-loop Control Systems
S.No. | Open-Loop Control System | Closed-Loop Control System |
1 | The controlled action is free from the output in the case of an open-loop control system. | Here the output relies on the controlled act of the system. |
2 | It is also known as a non-feedback control system. | It is also known as a feedback control system |
3 | The segments of the open-loop control system hold a controlled process and controller. | Some examples of these types of systems are TV remotes, automatic washing machines, immersion rods, traffic lights, etc. |
4 | It is simple to build this system. | It is complex to construct this system. |
5 | It is unreliable. | It is reliable |
6 | The precision exactness of this system mostly relies on calibration. | The accuracy depends on the feedback. |
7 | These systems are stable. | These are less stable as compared to the open-loop control system. |
8 | Here optimization is not allowed. | Optimization is allowed here. |
9 | It provides a quick response. | It is sluggish in terms of providing the response. |
10 | The calibration of this system is hard. | The calibration of this system is simple. |
12 | Open-loop control systems are nonlinear | These are linear. |
13 | Some the examples of these types of systems are TV remote, automatic washing machine, immersion rod, traffic lights, etc. | Some examples of these types of systems are pressure and speed, AC, control systems, toasters, and refrigerators. |