UNIT NO. IV

AC FUNDAMENTALS

Contents

Formation of Sinusoidal Waveform

Parameters related with AC

RMS and Average value

Phasor representation

Addition and Subtraction of AC Quantity

AC Through Pure R, L and C

AC and DC

Faradays Law of Electromagnetic Induction

Elementary generator

Position of the coil to get AC Voltage

Formation of sinusoidal waveform

+Peak Value

0 900 1800

2700 3600

t

Voltage or Current

Sinusoidal Waveform for Current or Voltage

Cycle

( - Peak Value)

Sinusoidal waveform of Alternating Current

Equation for Alternating Quantity

v= Vm sin θ volts i= Im sin θ Amp

Where θ=t=2πft

(R.M.S.) VALUE

Graphical Method to find RMS value

Analytical Method to find RMS value

RMS Value of Voltage and Current

Average Value by Graphical Method

Analytical Method for Average Value

PEAK FACTOR AND FORM FACTOR

PHASOR REPRESENTATION OF ALTERNATING QUANTITIES

PHASE

Phase Difference

Two coils with phase difference

PHASOR DIAGRAMS

Complex Notation of Phasors