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Andrey
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Файл:(EOD).Electric circuits.pdf
page 75
Next, consider the partial derivative for the reactance,
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RL + Rs) |
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XL + Xs) ) |
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XL = –Xs |
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6.3 3-PHASE CIRCUITS
•3-phase circuits are common in large scale power generators and delivery systems.
•These systems carry 3 phases of voltage, each 120 degrees out of phase, on three separate conductors. If these three wires are connected through a balanced load the sum of currents is zero. Most systems provide a fourth wire as a neutral.
generator
V1( t)
V2( t)
V3( t)
phase 1
load
neutral
phase 2
phase 3
= Vpeak sin ( ω |
t) = Vrms 0° |
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2π |
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= Vpeak sin ω |
t + |
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= Vrms |
120° |
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4π |
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= Vpeak sin ω |
t + |
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= Vrms |
240° |
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