Jawaharlal Nehru Technological University Anantapur 2010-1st Sem B.Tech Code :R7411304 4 IV (R07) Regular s, ember/ember ADAPTIVE CONTROL SYSTEMS - Question Paper

Code :R7411304 4
IV B.Tech I semester (R07) Regular Examinations, November/December 2010
ADAPTIVE CONTROL SYSTEMS
(Electronics & Control Engineering)
Time: three hours Max Marks: 80
ans any 5 ques.
All ques. carry equal marks
1. (a) discuss the merits and demerits of adaptive control system over conventional feedback control system.
(b) With relevant block diagrams, discuss the major kinds of adaptive control schemes.
2. (a) Consider the adaptive second-order system provided in ¯gure 2.
(b) Sketch the pole-zero diagram on s-plane for
i. KxKv = 1
ii. KxKv < 1
iii. KxKv > 1
(c) Sketch the energy density spectrum for the i), (ii), and (iii).
3. (a) Investigate the global properties of adaptive systems. When the parameters are such that the local equilib-
rium is stable.
(b) discuss in brief about analysis of indirect discrete-time self tuners.
4. Consider an integrator with a time delay T. for the sampling period h>T, the system is provided by the subsequent
equations:
A(q) = q(q ¡ 1)
B(q) = (h ¡ T)q + T = (h ¡ T)(q + b)
Where b = T=(h ¡ T) and d0 = 1
The noise is presumed to be characterized by C(q)=q(q+c); |c|<1. calculate the optimal minimum variance
controller and the lowest attainable output variance when
a) T=0.4 (the minimum phase)
b) T=0.6 ( the non-minimum phase)
5. discuss the design procedure using hyper stability in the case of unknown parameters.
6. (a) explain how a dual control issue can be solved using conditional distribution of the state theorem.
(b) discuss the subsequent class of sub optical dual controllers:
i. Constrained 1 step minimization
ii. Perturbation signals.
7. (a) What id meant by tuning of PI/PID controllers. discuss zeigler-Nichol's transient response and closed loop
methods for tuning controllers.
(b) An open loop step response of a system indicates a negative intercept of five units with a steady output of 0.98,
delay time of 0.02 sec and rise time of 1.2 sec. determine the parameters of PID controller to improve the
response use the subsequent table:
Controller Kc Ti Td
P 1/a - -
PI 0.9/a 3L -
PID 1.2/a 2L L/2
8. Write concise note on and three:
(a) Square root algorithm
(b) Averaging in stochastic system.
(c) Variable structure systems.
(d) Auto tuning based on relay feedback.

Earning:   Approval pending.