1. LTI system stability S-domain analysis
Lecture #09
LTI system stability
S-domain analysis
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2. Stability analysis Absolute Stability Relative Stability
Routh-Huwitz criteria
Relative Stability
Steady state error
Root locus
Bode plot
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3. Stability testing Properties of the polynomial coefficients :
Differing algebraic signs
Zero-valued coefficients
All of the same algebraic sign, non zero
At least one RHP root
Has imaginary axis roots or RHP roots or both
No direct information
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4. Routh-Hurwitz testing
The number of RHP roots of P(s) is the number of
algebra sign changes in the elements of the left column of the array.
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5. Example 1
Two roots in the RHP
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6. Example 2
no root in the RHP
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7. Example 3 n 移位次數移至0消失為止 Two roots in the RHP meiling chen
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8. Example 4
factor
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9. no root in the RHP
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10. Example 5 + -
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