Answer Happy

Consider a pH control problem that has the process transfer function: 4e-10s 50s +1 Gp(s): The time base is minute. a) Sketch by hand the Bode plot (AR and 4) for the transfer function Gp(s). (4 marks) b) Find the amplitude ratio (AR) and phase angle ($) for G₁(s) at w = 0.1689 rad/min. (3 marks) c) Consider the scenario where a proportional-only controller Ge(s) = K = 0.5 is used, so that the open-loop transfer function is G(s) = Ge(s)G, (s). Find the gain margin and phase margin. (5 marks) d) Consider the scenario where a proportional-integral controller Ge(s) = 0.5(1+) is used, and the open-loop transfer function is G(s) = Ge(s)Gp(s). Find the gain margin and phase margin. Discuss on the effect of integral control action on the gain and phase margin. (8 marks)