The motor speed can be controlled using a tachometer or current sensor, where the sensor detects the motor speed and sends feedback to the control system to change its speed.The temperature in the AC can be adjusted depending on the temperature of the room.In the water level controller, the level of water can be decided by the input water.In servo voltage stabilizer, the voltage stabilization can be attained by giving output voltage feedback to the system.So the applications of closed-loop control systems include the following.

There are different kinds of electronic devices that use a closed-loop control system. Similarly, for the positive feedback, the transfer function equation can be written asĬ(S)/ R(S) = G(S)/ Closed-Loop Control System Examples This is the transfer function of this system with negative feedback. Substitute this E(S) value in C(S), then we can get The closed-loop control system example is shown below. Because this loop can be achieved by connecting some portion of the output voltage to the input of the non-inverting terminal through a feedback loop using a resistor. The best example of this positive feedback in electronic circuits is an operational amplifier. This system is also named as regenerative feedback. The closed-loop system including a positive feedback signal can be connected to the input of the system is known as a positive feedback system. Types of Closed Loop Control SystemĬlosed-loop control systems are classified into two types depending on the feedback signal nature such as positive feedback signal and the negative feedback signal. The best example of a closed-loop control system is a traffic light control system including a sensor at the input. Therefore, these systems are also named as automatic control systems. In this arrangement, the control system output can be corrected automatically to get the preferred output. As an alternative of the input, this error signal can be given as an input of a controller.Ĭonsequently, the controller generates an actuating signal to control the plant. This feedback signal can be obtained from the elements of feedback in the control system by considering the system output as an input. In the above diagram, the error detector generates an error signal, so this is the variation of the input as well as the feedback signal. This type of control system can include more than one feedback. So the output can be controlled accurately by providing feedback to the input. When the control system includes a feedback loop, then the systems are known as feedback control systems. The basic elements of the closed-loop control system include error detector, controller, feedback elements & power plant. The block diagram of the closed-loop system is shown below.

Labview pid control block diagram