4. Block Diagrams: Topologies
Cascade Form:
Exception: Assumption that the interconnected subsystems do not
load adjacent subsystems.
Use K (amplifier), it has
high-impedance input so
it does not load previus
network. And has low
impedance output so it
looks like a pure voltage
source to subsequent
networks
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7. Block Diagrams: Moving Blocks
Algebra for Summing Junctions:
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8. Block Diagrams: Moving Blocks
Algebra for Pickoff Points:
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9. Block Diagrams: Example
Steps:
a) Collapse suming junction.
b) Form equivalent cascade system in
the forward and feedback paths.
c) Form equivalent feedback system
and multiply by cascaded G1(s).
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10. Block Diagrams: Example
Move G2(s) to the left past pickoff point to create parallel subsystems.
Reduce feedback system consisting of G3(s) and H3(s).
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11. Block Diagrams: Example
Reduce parallel pair of 1/G2(s) and unity.
Push G1(s) past right summing junction.
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12. Block Diagrams: Example
Collapse summing junction and two feedback elements.
Combine last two cascade blocks.
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13. Block Diagrams: Example
Reduce the remaining feedback system.
Combine last two cascade blocks.
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14. Analysis and Design of Feedback Systems:
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15. Analysis and Design of Feedback Systems:
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