Designing a circuit from a transfer function [linear control]

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SUMMARY

The discussion focuses on designing a controller with the transfer function \(\frac{5(s+0.5)(s+2)}{s(s+10)}\) for a linear control system. Key components include a gain of 5 and an integrator, necessitating a resistor-capacitor network to realize the transfer function. The Bilinear Transform is recommended for mapping the transfer function into the z-plane, with MATLAB's 'bilinear' function facilitating this conversion. The importance of ensuring a sampling time that is at least twice the highest frequency component is emphasized for accurate implementation.

PREREQUISITES
  • Understanding of transfer functions in control systems
  • Familiarity with analog circuit components (resistors, capacitors)
  • Knowledge of the Bilinear Transform and its application
  • Experience with MATLAB, specifically the 'bilinear' function
NEXT STEPS
  • Research the implementation of analog filters using resistor-capacitor networks
  • Learn about the Bilinear Transform and its applications in control systems
  • Explore MATLAB's capabilities for control system design and simulation
  • Study the principles of digital filter design and difference equations
USEFUL FOR

Control system engineers, electrical engineers, and students studying linear control systems who need to design controllers based on transfer functions.

Ian_Brooks
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Homework Statement



Linear Control Systems - 2006 past paper

If I wanted to design a controller with a transfer function of the form

[tex]\frac{5(s+0.5)(s+2)}{s(s+10)}[/tex]

How would I go about doing so?


Homework Equations



A constant gain is given as a constant
A differentiator will have an S term in the numerator
An integrator will have an S term in the denominator




The Attempt at a Solution



From the transfer function I can see that a Gain of 5 is used, and an integrator is required

How would i choose discrete circuit components to satisfy the above?

basically [tex]\frac{V_{out}}{V_{in}}[/tex] = [tex]\frac{(s+0.5)(s+2)}{(s+10)}[/tex]

So some resistor and capacitor network would be needed to realize the remaining transfer function. And an integrator would be needed with some capacitor fed back.

Still I'm quite confused on how to go about this
 
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This is probably not what you are looking for, but I can tell you how to implement it digitally.
(I am a software geek and I don't know how to map a s plane transfer function into analog components -- sorry).

The way I would map it into digital hardware or software is to use the Bilinear Transform to map the transfer function into the z plane and then the time domain expression can be read out directly and easily implemented in hardware or software as shift registers. Matlab provides the function bilinear to do this conversion. Just make sure your sampling time is fast enough (2 times the highest frequency component).
 
well i have implemented it with software before in a course called real time instrumentation where we made digital filters and represented our transfer functions as difference equations - however, sadly i can't draw from that to get the 4 marks for this question.

any other help?
 

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