Description : If stability error for step input and speed of response be the criteria for design, what controller would you recommend (1) P controller (2) PD controller (3) PI controller (4) PID controller

Answer : If stability error for step input and speed of response be the criteria for design, what controller would you recommend (1) P controller (2) PD controller (3) PI controller (4) PID controller

Description : Define stability. Sketch the root locations in the s-plane for stable and unstable system.

Answer : Stability: The system is said to be stable if it produces bounded output for a bounded input. It is used to define usefulness of the system. The stability implies that the system performance should not ... absence of the input, output may not return to zero it shows certain output without input.