what is the difference between control system and feedback control system
Answers
Feedback control system
Feedback control measures the output of a process, calculates the error in the process and then adjusts one or more inputs to get the desired output value.
The feedback control reacts only to the process error (the deviation between the measured output value and set point). So, it is called as REACTIVE CONTROL.
Feedback control measures the output and verifies the adjustment results. So, it is called as CLOSED LOOP CONTROL
Feedforward control system
Feedforward control measures one or more inputs of a process, calculates the required value of the other inputs and then adjusts it.
Feedforward control has to predict the output as it does not measure output. So, it is sometimes called as PREDICTIVE CONTROL.
Feedforward control does not check how the adjustments of inputs worked in the process. So, it is referred to as OPEN LOOP CONTROL.