CONTROL SYSTEMS JNTU previous years question papers
(a) Characteristic equation
(b) Order of a transfer function
(c) Type of a transfer function
(d) Poles and zeros of a transfer function. 
x2 = ax1 + fx2
x3 = bx2 + ex4
x4 = cx3 + hx5
x5 = dx4 + gx2
(b) The response of a system subjected to a unit step input is c(t) = 1 + 0.2e-60t -1.2e-10t
Obtain the expression for the closed loop transfer function? Also determine the Un damped natural frequency and damping ratio of the system? [8+8]
(a) addition of open loop poles
(b) addition of open loop zeros. 
(b) For a system the resonant peak is 1 dB an ?n = p10 r/s. Find resonant frequency.Also find the phase angle of closed loop transfer function at resonant frequency. [6+10]
G(s) = 4s+1s2(s+1)(2s+1) Sketch the Nyquist plot & hence determine the stability of the system. [2+14]
(b) What is a lag compensator, obtain the transfer function of lag compensator and draw pole-zero plot?
(c) Explain the different steps to be followed for the design of compensator using Bode plot? [3+3+10]
(b) Define state variables.
(c) Obtain the state variable representation of an armature controlled D.C Servomotor?