Digital Control Systems Mid - II, November - 2014

1.The characteristic equation P(z) = z4 -1.273+0.07z2+0.3z-0.08 The given system is
  • stable
  • unstable
  • marginally
  • stability cannot be determined
Answer: A
2.The stability test that can be applied directly to characteristic equation without solving for roots is
  • schur – cohn stability test
  • jury stability test
  • routh stability
  • all the above
Answer: D
3.The design of objective of state observer is to select Ge such that Ce(K) will approach _______ as fast as possible
  • C(K)
  • Xe(K)
  • Ge(K)
  • Ce(K)
Answer: A
4.The reduced order observer is of the __________ order
  • (n-q) th
  • (n) th
  • (q) th
  • (n+q)nth
Answer: A
5.Bilinear transformation integration in a digital PID controller is given by D1(z) = KI ________
  • a
  • b
  • c
  • d
Answer: D
6.The range of K for which system
  • 0
  • k<<2
  • 1.5
  • -0.011
Answer: D
7.In Routh array method, with row of all __________ an auxiliary equation A(w)=0 is formed by using coefficients of the row just above the row of zeros.
  • ones
  • zeros
  • negative
  • infinity
Answer: B
8.When we want the states to approach zero starting from any arbitrary initial state, the design problem is known as ___________ problem.
  • tracking
  • regulation
  • both a and b
  • undefined
Answer: B
9.x (k +1) = Ax(k) + Bu (k ) A necessary and sufficient condition for arbitrary pole placement is that the pair (A,B) must be _________
  • observable
  • zero
  • controllable
  • both a and c
Answer: C
10.The roots of the characteristic equation is a function of K which varies from
  • -1 to 1
  • -∞ to +∞
  • -1 to +∞
  • -∞ to 1
Answer: B
11.The stability methods applicable to continuous-data systems, where outputs are measured at ______________ time interval.
Answer: Discrete
12.The condition for state controllability is ______________
Answer: [D ; CB ; CAB ; CA2 B………..]
13.Expand BIBO ______________
Answer: Bounded input and bounded output
14.The stability of characteristic equation p(z)=z3-1.3z2-0.08z+0.24 is ___________
Answer: Marginally stable
15.The relative stability of a digital control system cannot be studied in z-plane by superimposing the constant-ζ, δ, and ωn loci on the ____________ diagram.
Answer: Root locus
16.An observer that estimates fewer than ‘n’ states is called _____________ observer.
Answer: Reduced order
17._____________ formula offers an elegant way of determining the feedback matrix K for pole placement using information from the required closed – loop characteristic equation without converting the system to controllable canonical form.
Answer: Ackermann’s
18.Design of digital control system methods are conventional and others depends on the _________________ formulations.
Answer: State variable
19.The most versatile way of compensating a digital control system is by use of a _____________
Answer: Digital controllers
20.The response in which a unit step response that reduces its steady state value of unity on 0.1sec, and there should be little or no ripple between the sampling instants, that is called ____________ response.
Answer: Dead beat