State Space Model of an RL Circuit

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SUMMARY

The discussion centers on deriving a state-space model for an RL circuit with input v(t) and output vL(t). The user initially applied Kirchhoff's Current Law (KCL) in the time domain to develop a state-space model, then used mesh analysis to derive a transfer function. Discrepancies between the two transfer functions indicate potential errors in either the state-space analysis or the mesh analysis. The community suggests reviewing the time-domain method for possible omissions, specifically regarding the V(t) term.

PREREQUISITES
  • Understanding of state-space representation in control systems
  • Familiarity with Kirchhoff's Current Law (KCL)
  • Knowledge of mesh analysis in electrical circuits
  • Basic concepts of transfer functions and their derivation
NEXT STEPS
  • Review the derivation of state-space models for RL circuits
  • Study the application of Kirchhoff's Current Law (KCL) in time-domain analysis
  • Learn about mesh analysis techniques for circuit analysis
  • Explore the relationship between state-space models and transfer functions
USEFUL FOR

Electrical engineering students, circuit designers, and anyone involved in control systems analysis and design.

YoshiMoshi
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Homework Statement



For the given circuits, identify state variables and derive a state-space model for each.
Assume the input is v(t) and the output is vL(t).

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Homework Equations

The Attempt at a Solution


[/B]
So my issue is that I solved this problem using two different methods. First method I used was trying to find the state space model directly using KCL in the time domain. I then took my state space model used derived using this method and found the transfer function. I then found the transfer function directly using mesh analysis. For some reason I got two different transfer functions. So that means either my state space analysis from my first method was incorrect, or the second transfer function I found using mesh analysis was incorrect. I'm not exactly sure what I did was incorrect, my transfer function using mesh analysis, or my state space analysis. Any help would be greatly appreciated.
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The form of your answer using the 2nd method looks correct (bandpass filter), but I didn't check the math in detail
upload_2018-10-11_13-36-56.png

But it seems like you dropped a V(t) term in you answer using the first time-domain method? (Or I could be missing something)...
upload_2018-10-11_13-38-30.png
 

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