Stability of Digital Control System

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Stability is a basic requirement for digital and analog control systemsAsymptotic StabilityBounded Input Bounded Output

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Observe

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Asymptotic Stability for Digital Control SystemBIBO Stability

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Internal Stability

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Routh-Hurwitz CriterionBilinear transformation transforms the inside of the unit circle to the LHP (Left Half Plane).Bilinear TransformationExample :Substituting the bilinear transformationstability conditions

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Jury Criterion

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Example :We compute the entries of the Jury table using the coefficients of the polynomial

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Transient and Steady State AnalysisTransient Analysis

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Steady State Error AnalysisFinal Value Theorem

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1) For unity feedback in figure below,2)

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