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MathematicalPhysicist
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1. Homework Statement + the attempt at solution
I have the next transfer function:
[tex]H(s)=\frac{P(s)}{1+C(s)P(s)}[/tex]
where [tex]P(s)=\frac{20}{(s^2-2s+9)(s+100)}[/tex]
[tex] C(s)=m(s+40)[/tex]
Now I want to find the settling time and overshoot of [tex]H(s)[/tex] as [tex]m\rightarrow \infty[/tex] to whithin 5 percent accuracy.
Now what I thought when [tex]m\rightarrow \infty[/tex] [tex]H(s)\approx \frac{1}{C(s)}[/tex].
So basically in this case the quadratic equation (in the notation of next webpage:
http://wikis.lib.ncsu.edu/index.php/Second_Order_Dynamics) is:
[tex]s^2+(-2s+20ms)+(9+800m)[/tex]
Is this right or am I just rambling nonsense here, I am lost here.
I know that when we have the Quadratic ploynomial in the denominator of [tex]G(s)=P(s)C(s)[/tex] s.t:
[tex] s^2+2\zeta \omega_n s +\omega_n ^2[/tex]
then the settling time is given by:
[tex]t_s \approx \frac{3}{\zeta \omega_n}[/tex]
and the overshoot is given by:
[tex] \sigma = exp(\frac{-\zeta \pi}{\sqrt{1-\zeta^2}})[/tex]
Any hints or advice are welcomed and much appreciated.
Thanks.
I have the next transfer function:
[tex]H(s)=\frac{P(s)}{1+C(s)P(s)}[/tex]
where [tex]P(s)=\frac{20}{(s^2-2s+9)(s+100)}[/tex]
[tex] C(s)=m(s+40)[/tex]
Now I want to find the settling time and overshoot of [tex]H(s)[/tex] as [tex]m\rightarrow \infty[/tex] to whithin 5 percent accuracy.
Now what I thought when [tex]m\rightarrow \infty[/tex] [tex]H(s)\approx \frac{1}{C(s)}[/tex].
So basically in this case the quadratic equation (in the notation of next webpage:
http://wikis.lib.ncsu.edu/index.php/Second_Order_Dynamics) is:
[tex]s^2+(-2s+20ms)+(9+800m)[/tex]
Is this right or am I just rambling nonsense here, I am lost here.
Homework Equations
I know that when we have the Quadratic ploynomial in the denominator of [tex]G(s)=P(s)C(s)[/tex] s.t:
[tex] s^2+2\zeta \omega_n s +\omega_n ^2[/tex]
then the settling time is given by:
[tex]t_s \approx \frac{3}{\zeta \omega_n}[/tex]
and the overshoot is given by:
[tex] \sigma = exp(\frac{-\zeta \pi}{\sqrt{1-\zeta^2}})[/tex]
Any hints or advice are welcomed and much appreciated.
Thanks.