B.TECH - Semester 6 control systems Question Paper 2020 (jan)
Practice authentic previous year university questions for better exam preparation.
Sample Questions
- Write the force balance equation of ideal mass element.
- Distinguish between open loop and closed loop control systems
- What is signal flow graph?
- Define settling time.
- What is transient response and steady state response?
- What is Nyquist stability criterion?
- What are the advantages of Bode plot?
- What is the effect of addition of zero to the system?
- What is the disadvantage in proportional controller?
- What is state variable? ( $\mathbf{1 0} \boldsymbol{\times} \mathbf{2} \boldsymbol{=} \mathbf{2 0}$ Marks) P.T.O. Answer any one questions from each Module.
- (a) Obtain the transfer function of the mechanical system shown figure. 10
- (b) Derive the transfer function of field controlled DC motor.
- (a) Using block diagram reduction technique, find the transfer function for each input. 10
- (b) Find $\mathrm{C} / \mathrm{R}$ for the signal flow graph shown in following figure.
- (a) Derive the expressions for the rise time $t_{p}$ and peak time $t_{p}$.
- (b) A unity feedback system is characterized by an open loop transfer function $G(s)=\frac{K}{s(s+10)}$. Determine the gain $K$ so that the system will have a damping ratio of 0.5 , For this value of K , determine settling time, peak overshoot and ti...
- (a) A unity feedback system is given as $G(s)=\frac{5}{s(s+5)}$. The input to the system is described by $r(t)=6+5 t$. Find the generalized error coefficients and steady state error.
- (b) Use Routh's criterion to determine the number of roots of the following equation which lie in the right half of S-plane.
- (i) $s^{6}+s^{5}+2 s^{4}+s^{3}+2 s^{2}+5 s+6=0$ (ii) $s^{4}+9 s^{3}+4 s^{2}-36 s+6=0$
- Draw the bode plot for a unity feedback system with $G(s)=\frac{K(s+0.3)}{(s+4)\left(s^{2}+30 s+20\right)}$ Where $\mathrm{K}=2000$. Determine the gain margin, phase margin. Comment on stability. Determine the value of K to obtain phase margin of $30...
- (a) Sketch the root locus for a system whose loop transfer function is $$ G(s) H(s)=\frac{k(s+1)}{s^{2}+4 s+13} $$
- (b) Sketch the Nyquist plot for a system with open loop transfer function $G(s) H(s)=\frac{k(s+1)(1+0.4 s)}{(1+8 s)(s-1)}$. Determine the range of K for which the system is stable.
- (a) Determine the state controllability and observability for the system represented by the following state equation. $$ \begin{gathered} X=\left[\begin{array}{ccc} 0 & 1 & 0 \\ 0 & 1 & 1 \\ 0 & -2 & -3 \end{array}\right] x+\left[\begin{array}{l} 0 ...
- (b) Determine the stability of sample data control systems described by the following characteristic equation. $$ F(z)=z^{4}-1.4 z^{3}+0.4 z^{2}+0.08 z+0.002 $$
- (a) A linear time invariant system is described by the following state model. $$ \begin{gathered} X=\left[\begin{array}{ccc} 0 & 1 & 0 \\ 0 & 0 & 1 \\ -6 & -11 & -6 \end{array}\right] x+\left[\begin{array}{l} 0 \\ 0 \\ 2 \end{array}\right] u \\ Y=\l...
- (b) Consider a unity feedback system with open loop transfer function, $G(s)=10 /(s+1)(s+2)$. Design a PI controller so that the closed loop has damping ratio of 0.707 and natural frequency of oscillation as $1.2 \mathrm{rad} / \mathrm{sec} .10$ ( $\...