Rangkaian arus bolak-balik RANGKAIAN ELEKTRIK I Oleh : Ir. Hery Purnomo, MT Rangkaian arus bolak-balik

Gelombang sumber tegangan DC Baterai AC Genset

Pembangkit listrik (Generator AC)

Penemu Peralatan arus bolak-balik (gel. sinusoida) Nikola Tesla Thomas Edison George Westinghouse

Persamaan gel. sinusoida

v(t)  Vm sin(t  )

V2 mendahului (leading) terhadap V1 V1 terbelakang (laging) terhadap V2

Sebutkan kedudukan gelombang tegangan

Gelombang tegangan dan arus Arus (i) mendahului tegangan (v) dengan beda fasa Φ

Tuliskan persamaan gelombangnya

Sinusoida: perubahan sudut Radians Degree π = 3.142

Gelombang air laut SINUSOIDA ….??

Nilai rata-rata Gelombang sinusoida

Nilai efektif / rms gel. sinusoida

Nilai efektif gel. sinusoida Peak = 163 V RMS = 115 V 115 = 0,707 x 163

Catatan : Tegangan Arus Arus sesaat : i(t) Arus maksimum/puncak : Im Tegangan sesaat : v(t) Tegangan maksimum/puncak : Vm Tegangan efektif/rms : Vef = Vrms = V Arus Arus sesaat : i(t) Arus maksimum/puncak : Im Arus efektif/rms : Ief = Irms = I

Pemakaian nilai efektif Sumber tegangan Jala-jala (PLN), selalu menggunakan tegangan efektif misal : tegangan 220 V atau 380 V, 50 Hz Peralatan listrik, tegangan yang tercantum pada papan nama adalah tegangan efektif. Peralatan ukur (voltmeter, ampermeter), menunjukkan nilai efektifnya

CONTOH (1) A sinusoidal current has a maximum amplitude of 20A. The current passes through one complete cycle in 1 ms. The magnitude of the current at zero time is 10A. a) What is the frequency of the current in Hz? b) What is the value of the angular frequency? c) Write the expression for i(t) in the form Im cos(ωt + ). d) What is the rms value of the current?

CONTOH (2) A sinusoidal voltage is given by the expression v = 300cos(120t + 30o) a) What is the frequency in Hz? b) What is the period of the voltage in milliseconds? c) What is the magnitude of v at t = 2.778 ms? d) What is the rms value of v?

Teknik Analisis Rangkaian Elektrik DC (Direct current) AC (Alternating current) Circuits Voltage Current Voltage Current Constant voltage Constant current Time Phasor Concept Frequency Rules: Ohm’s law Kirchoff’s law Techniques: Mesh Analysis Node Analysis Superposition Thevenin/ Norton Techniques: Mesh Analysis Node Analysis Superposition Thevenin/ Norton Rules: Ohm’s law Kirchoff’s law

Goal Kapan tercapai ??

TERIMA KASIH