Pi controllers a can eliminate constant disturbances from th

Pi controllers:

a. can eliminate constant disturbances from the ouput but they cannot increase the Bandwidth of the loop.

b. can eliminate constant disturbances from the ouput but they always increase the Bandwidth of the loop.

c. can eliminate constant input disturbances from the ouput but they increase the Bandwidth of the loop.

d. can eliminate constant disturbances from the ouput and always decrease the Bandwidth of the loop.

e. none of the above

Answers b and d are incorrect. Please solve and explain select the best option

Solution

OPTION (C) IS CORRECT

P-I controller is mainly used to eliminate the steady state error resulting from P controller. However, in terms of the speed of the response and overall stability of the system, it has a negative impact. This controller is mostly used in areas where speed of the system is not an issue. Since P-I controller has no ability to predict the future errors of the system it cannot decrease the rise time and eliminate the oscillations. If applied, any amount of I guarantees set point overshoot