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A system is defined as marginally stable when

A system is defined as marginally stable when Correct Answer One or more poles lie in the imaginary axis

Concept:

Stability:

  • Any system is called a stable system if the output of the system is bounded for any bounded input.
  • The stability of any system depends on only location poles but not on the location of zeros.
  • If all the poles are located in the left half of the s-plane, then the system is stable.
  • If one or more poles are located on the right side of the s-plane, then the system is unstable.
  • If one pair of poles located on the imaginary axis, then the system is marginally stable.
  • If more than one pair of poles on the imaginary axis, then the system is unstable.
  • Two or more poles at the origin will make the system unstable.

Important Points

  1. The minimum phase system will have no poles and zeros lie right half of the s-plane.
  2. Non-minimum phase systems usually have one more zeros or poles lie right half of the s-plane.

 

If the roots are located on the imaginary axis then the system may be marginally stable or unstable, If only one pair of poles located on the imaginary axis, then the system is marginally stable.

Related Questions

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