Ch1 b TRANG BỊ ĐIỆN, ĐIỆN TỬ TRONG MÁY CÔNG NGHIỆP

Ngun lý tạo ra dịng điện xoay chiều hình sin
Biểu thức tức thời
Đồ thị vectơ
Mạch thuần trở, thuần cảm, thuần dung
R-L-C nối tiếp, R-L-C song song
Mạch cộng hưởng
Hệ số công suất
Vol 2 – Chapter 1~7

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It is true that in some cases AC holds no practical
advantage over DC
With AC, it is possible to build electric generators,
motors and power distribution systems that are far
more effcient than DC


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Mutual induction


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Change from one polarity to the other is a smooth
one, the voltage level changing most rapidly at the
zero ("crossover") point and most slowly at its
peak.

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Frequency?
Amplitude?

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AC?

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Peak
Peak–to–peak
RMS
Average

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Relevant?


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Simple parallel (tank circuit) resonance

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Simple Harmonic Motion (SHM)
With capacitive and inductive reactances equal to
each other, the total impedance increases to infinity,
meaning that the tank circuit draws no current from
the AC power source!

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Simple series resonance

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Resonant frequency?

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Applications?


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Mixed frequency waveform
Other waveshapes
Spectrum analysis

V & I are in phase

V leads I

V lags I


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Find the current produced by the source.