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25th November 2013, 02:38 #1
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control system, poles and stability response
Can you help me compare these results? They're the simulations of a closed loop system . When we change the poles, (in this case, there are 4 poles), the response system also changes. The 4 poles involves 2 complex numbers and 2 integers, but I don't see the relationship between the poles and the response. I don't see an exact description. I mean, a description like:
if the real number is increased, then the response would be more oscillatory or if the imaginary part is smaller, then the faster the convergence to 0.
Help, please?

25th November 2013, 02:38

25th November 2013, 04:03 #2
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Re: control system, poles and stability response
Can you help me compare these results? They're the simulations of a closed loop system . When we change the poles, (in this case, there are 4 poles), the response system also changes. The 4 poles involves 2 complex numbers and 2 integers, but I don't see the relationship between the poles and the response. I don't see an exact description. I mean, a description like:
if the real number is increased, then the response would be more oscillatory or if the imaginary part is smaller, then the faster the convergence to 0.
Help, please?
Hi MissP.25_5
I don't see anything surprising ! when you change location of poles of a circuit response of a circuit will be involved by some changes which depends on where are the poles exactly .
A suitable Article from MIT can lead you through a good understanding :
http://www.google.com/url?sa=t&rct=j...56988011,d.cGU
Best Wishes
GoldsmithWhen you sensed that i can help you , feel free to ask me .
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Experience is a good professor of mine !
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The only thing that i couldn't understand yet , is why humans should fight together ? why not helping each other to have a better world ?

25th November 2013, 04:03

25th November 2013, 04:25 #3
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Re: control system, poles and stability response

25th November 2013, 04:25

25th November 2013, 09:38 #4
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Re: control system, poles and stability response
MissP  it is not easy to answer your question because it is not clear which parameters of the closedloop sysytem are shown.
Watching the first line I see something like a step response, correct?
In this context, I am confused about the last line showing an input. Which input?
As a general (and preliminary) answer:
A complex pole pair causes overshoot in the step response. When the (negative) real part of these poles come closer to the origin (imag. parts constant) the overshoot increases.
Moreover, a negative real pole (at s=sigma) causes a damping of the step response corresponding to exp(sigma*t). Thus, the duration of the step response is inverse proportional to sigma.
I think, the time response (first line) can confirm these statements.Last edited by LvW; 25th November 2013 at 09:52.
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25th November 2013, 10:18 #5
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25th November 2013, 10:18

25th November 2013, 11:04 #6
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Re: control system, poles and stability response
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