Post on 28-Feb-2021
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EECE421 Power System Analysis
Chapter 3: Transmission Line Serial Impedance
Conductor Types
CopperAluminum
SolidStrands
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Conductor Types
CopperAluminum
SolidStrands
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Conductor Types ‐ ACSR
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3.2 Resistance
Diameter: mil = 10‐3 in = 1/1000 [in]
Area: cmil [circular mil]= (π/4)*mil2
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3.2 Resistance
Diameter: mil = 10-3
in = 1/1000 [in]
Area: cmil [circular mil] = (π/4)*mil2
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3.2 Resistance
Conductivity: Area (A): m^2 for SI cmil for US
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3.2 ResistanceTemperature Dependency
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3.2 Resistance
Skin Effect
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Ex 3.1 (on All Aluminum Marigold stranded conductor)
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Ex 3.1 (on All Aluminum Marigold stranded conductor)
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3.3 Field Theory and Inductance
Changing flux Induced voltage Circuit property (Inductance L)
3.4 Definition of Inductance2 fundamental equations:(1) Change of flux linkage
induced voltage(2) Change in current the amount of voltage induction
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3.4 Definition of Inductance2 fundamental equations:(1) Change of flux linkage
induced voltage(2) Change in current the amount of voltage induction
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3.4 Definition of InductanceUnder linear relationship of current (i) and flux linkage (τ)
Phasor
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3.4 Definition of InductancePhasor
Mutual Inductance
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3.5 Inductance of a conductor due to internal fluxFlux Linkage (“effective flux”): flux liking a number of coils or coil turns (in our discussion here) flux linking to a portion of (or full) the current in the conductor
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3.5 Inductance of a conductor due to internal flux
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3.5 Inductance of a conductor due to internal flux
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3.5 Inductance of a conductor due to internal flux
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3.5 Inductance of a conductor due to internal fluxFlux Linkage (dψ)
Flux linkage for the current inside the conductor
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3.5 Inductance of a conductor due to internal flux
Inductance due to internal flux (Lint)
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3.6 Flux Linkage between 2 external points
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3.6 Flux Linkage between 2 external points
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3.7 Inductance of a Single Phase 2‐wire Line
Current flows are forward and reverse (or return)r: conductor radiusD: Distance between the conductors (center to center)
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3.7 Inductance of a Single Phase 2‐wire Line
Current flows are forward and reverse (or return)d1: a point between conductor 1 and 2d2: a point along the length of the conductor diameter
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3.7 Inductance of a Single Phase 2‐wire Line
Current flows are forward and reverse (or return)d1: a point between conductor 1 and 2d2: a point along the length of the conductor diameter
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3.7 Inductance of a Single Phase 2‐wire Line
Current flows are forward and reverse (or return)d1: a point between conductor 1 and 2d2: a point along the length of the conductor diameter
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3.7 Inductance of a Single Phase 2‐wire Line
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3.7 Inductance of a Single Phase 2‐wire Line
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3.8 Flux Linkage of one conductor in a group
P: a point in the spaceFlux linkage between a conductor to the point P due to the current I1
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3.8 Flux Linkage of one conductor in a group
P: a point in the spaceFlux linkage between a conductor to the point P due to the current I2
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3.8 Flux Linkage of one conductor in a group
P: a point in the spaceFlux linkage between a conductor to the point P due to the current I2
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3.8 Flux Linkage of one conductor in a group
P: a point in the spaceFlux linkage between a conductor to the point P due to the current I2
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3.9 Inductance of Composite‐Conductor Lines
Stranded conductorComposite Conductor: 2 or more elements or strandsWe assume that composite conductors share the current equally
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3.9 Inductance of Composite‐Conductor Lines
We assume that composite conductors share the current equallyLet’s pick the filament aI/nI/m
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3.9 Inductance of Composite‐Conductor Lines
We assume that composite conductors share the current equallyLet’s pick the filament aI/nI/m
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3.9 Inductance of Composite‐Conductor Lines
The filaments are in parallelInductance then must be divided by the number of elementsUsing Log A + Log B = Log (AB)
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3.9 Inductance of Composite‐Conductor Lines
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Ex 3.2 Inductance Calculation
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GMD calculation between X and Y sides
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GMR calculation for X side Lx Calculation
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GMR calculation for Y side Ly Calculation
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L = Lx + Ly
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