Anna University Coimbatore 2008 B.E Electrical and Electronics Engineering Control system unit 1 - Question Paper

Relative stability is the degree of closeness of the system,it an indication of strength or degree of stability.
29.What are the 2 segments of Nyquist contour.
i. An finite line segment C1 along the imaginary axis.
ii. An arc C2 of infinite radius.
30.What are root loci.
The path taken by the roots of the open loop transfer function when the loop gain is varied from 0 to a are called root loci.
31.What is a dominant pole.
The dominant pole is a air of complex conjugate pair which decides the transient response of the system.
32.What are the main significances of root locus.
i. The main root locus technique is used for stability analysis.
ii. Using root locus technique the range of values of K, for as table system can be determined
33.What are the effect of adding a zero to a system.
Adding a zero to a system increases peak overshoot appreciably.
34.What are N circles.
If the phase of closed loop transfer function with unity feedback is a, then tan a will be in the form of circles for every value of a. These circles are called N circles.


35.What is control system?
A system consists of a number of components connected together to perform a specific function . In a system when the output volume is controlled by varying the input volume then the system is called control system.

36.What are the 2 major kinds of control system?
the 2 major kinds of control system are open loop and closed loop

37.Define open loop control system.

The control system in which the output volume has no effect upon the input volume are called open loop control system. This means that the output is not feedback to the input for correction.

38.Define closed loop control system.
The control system in which the output has an effect upon the input volume so as to maintain the desired output value are called closed loop control system.

39.What are the components of feedback control system?
the components of feedback control system are plant , feedback path elements, fault detector and controller.

40.Define transfer function.

The T.F of a system is described as the ratio of the laplace transform of output to laplace transform of input with zero initial conditions.

41.What are the basic elements used for modeling mechanical translational system.
Mass, spring and dashpot

42.What are the basic elements used for modeling mechanical rotational system?
Moment of inertia J,fdashpo with rotational frictional coefficient B and torsional spring with stiffness K

Earning:   Approval pending.