Transcript Document

Lecture 17: Analysis with Sinusoidal
Sources, Transformers
Nilsson 9.7-9.12
ENG17 : Circuits I
Spring 2015
May 26, 2015
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Impedance and Reactance
2
Review
Find vo(t)
3
Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
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Impedances in Series
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Impedances in Parallel
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Delta-to-Wye
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Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
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Source Transformations
Same as before, but now with impedances
9
Thevenin-Norton Equivalents
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Example
Find using
source
transformation
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Example
Find Thevenin
Equivalent
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Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
13
Node-Voltage Example
Find Ia, Ib, Ic
14
Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
15
Mesh-Current Example
Find Va, Vb, Vc
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Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
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Phasor Diagrams
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Example
Use phasor diagram to find R that will cause
resistor current (iR) to lag the source current (iS)
by 45° when ω = 5 krad / s.
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Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
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Transformer Circuit
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Frequency Domain Circuit
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Overview
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
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Ideal Transformer
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Sign Convention
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Impedance Matching
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Example
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Recap
• Series / Parallel
Simplifications
• Source
Transformations
• Node-Voltage
• Mesh-Current
• Phasor Diagrams
• Transformers
• Ideal Case
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