Define stability. Sketch the root locations in the s-plane for stable and unstable system.

Define stability. Sketch the root locations in the s-plane for stable and unstable system.
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1 Answer

Answer :

Stability: The system is said to be stable if it produces bounded output for a bounded input. It is used to define usefulness of the system. The stability implies that the system performance should not change even if there are small changes in system input. Any control system must be stable. 

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The system is said to be stable if poles of closed loop the system lies on left half of s-plane 

The system is said to be unstable if poles closed loop of the system lies on right half of s-plane

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STABILITY : A linear time invariant system is said to be stable if the system is excited by a bounded input, output is also bounded and controllable. In the absence of the input, output must tend to zero irrespective of the initial condition. 

UNSTABLE: A linear time invariant system is said to be unstable if for a bonded input it produces unbounded output. In absence of the input, output may not return to zero it shows certain output without input. 

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