Name of the College : Noorul Islam College of Engineering
University : Anna University
Degree : B.E
Department : Electrical & Electronic Engineering
Subject Code/Name : EC 1304 – Control Systems
Year : III
Semester : V
Document Type : Question Bank
Website : niceindia.com
Download :https://www.pdfquestion.in/uploads/ni…ROL_SYSTEM.pdf
NICE Control Systems Question Paper
Part – A
1.What is frequency response?:
A frequency responses the steady state response of a system when the input to the system is a sinusoidal signal.
Related : Noorul Islam College of Engineering EE1202 Circuit Analysis B.E Question Bank : www.pdfquestion.in/2980.html
2.List out the different frequency domain specifications?:
The frequency domain specification are
i)Resonant peak. ii)Resonant frequency.
3.Define –resonant Peak (µr)?:
The maximum value of the magnitude of closed loop transfer function is called resonant peak.
4.Define –Resonant frequency(µf)?:
The frequency at which resonant peak occurs is called resonant frequency.
5.What is bandwidth?:
The bandwidth is the range of frequencies for which the system gain Is more than 3 dbB.The bandwidth is a measure of the ability of a feedback system to reproduce the input signal ,noise rejection characteristics and rise time.
6.Define Cut-off rate?:
The slope of the log-magnitude curve near the cut-off is called cut-off rate. The cut-off rate indicates the ability to distinguish the signal from noise.
7.Define –Gain Margin?:
The gain margin,kg is defined as the reciprocal of the magnitude of the open loop transfer function at phase cross over frequency.
8.Define Phase cross over?:
The frequency at which, the phase of open loop transfer functions is called phase cross over frequency w pc.
9.What is phase margin?:
The phase margin ,g is the amount of phase lag at the gain cross over frequency required to bring system to the verge of instability.
11.Define Gain cross over?:
The gain cross over frequency w gc is the frequency at which the magnitude of the open loop transfer function is unity..
12.What is Bode plot?:
The Bode plot is the frequency response plot of the transfer function of a system. A Bode plot consists of two graphs. One is the plot of magnitude of sinusoidal transfer function versus log w.The other is a plot of the phase angle of a sinusoidal function versus log w.
13.What are the main advantages of Bode plot?:
The main advantages are :
i) Multiplication of magnitude can be in to addition.
ii) A simple method for sketching an approximate log curve is available.
iii) It is based on asymptotic approximation. Such approximation is sufficient if rough information on the frequency response characteristic is needed.
iv) The phase angle curves can be easily drawn if a template for the phase angle curve of 1+ jw is available.
14.Define Corner frequency?:
The frequency at which the two asymptotic meet in a magnitude plot is called corner frequency.
15.Define Phase lag and phase lead?:
A negative phase angle is called phase lag.
A positive phase angle is called phase lead.
16.What are M circles?:
The magnitude of closed loop transfer function with unit feed back can be shown to be in the for every value if M.These circles are called M circles.
17.What is Nichols chart?:
The chart consisting if M & N loci in the log magnitude versus phase diagram is called Nichols chart.
18.What are two contours of Nichols chart?:
Nichols chart of M and N contours, superimposed on ordinary graph. The M contours are the magnitude of closed loop system in decibels and the N contours are the phase angle locus of closed loop system.
PART – B
Unit1 :
1. For a given mechanical or electrical or electromechanical system derive the transfer function.
** Free body diagram
** Differential equation
** Transfer function
2.Determination of the overall transfer function using Block diagram reduction technique.
** Reduction of block diagram
** Determination of Transfer function
3. Determination of the overall transfer function from the given signal flow graph using Mason’s gain formula.
** Reduction of signal flow graph
** Apply masons gain formula
4.Write the procedure for constructing the block diagram of a given mechanical or electrical or electromechanical system.
** Write the differential equation
** Develop block diagram
5.Find the electrical analogical variables of a mechanical rotational system.
** Write the differential equation
** Draw the equivalent electrical network
Unit II :
1.Derive the expressions of the time domain specifications for a second order system with unit step input.
** Time response of second order system
** Rise time
** Peak time
** Peak overshoot
** Settling time
2.Find the time response of a first order system for various standard inputs.
** Apply the input
** Solve using partial differential equation
** Apply inverse Laplace transform