Control Systems - Study Mode
[#1] Consider the following statements with reference to frequency-domain approaches to analysis of feedback to control system 1. The approach needs and accurate mathematical description of the system 2. The method is independent of the complexity of systems 3. The method gives an approach for trial and error design Which of the above statements are correct?
Correct Answer
(D) 1, 2 and 3
[#2] The transfer function of a plant is $$Tleft( s
ight) = frac{5}{{left( {s + 5}
ight)left( {{s^2} + s + 1}
ight)}}.$$ xa0 xa0 The second-order approximation of T(s) using dominant pole concept is
Correct Answer
(D) $$frac{1}{{{s^2} + s + 1}}$$
[#3] The correct sequences of steps needed to improve system stability is:
Correct Answer
(D) Use negative feedback, reduce gain, and insert derivative action
[#4] The phase-lead network function $${G_C}left( s
ight) = frac{{s + frac{1}{T}}}{{s + frac{1}{{aT}}}},$$ xa0 xa0where a < 1 would provide maximum phase-lead at a frequency of:
Correct Answer
(C) $$frac{1}{{Tsqrt a }}$$
[#5] Identify the matrix that can be a state transition matrix.
Correct Answer
(D) [phi = left[ {x08egin{array}{*{20}{c}}
{{e^{ - t}}}&0\
0&{{e^{ - 2t}}}
end{array}}
ight]]