Transcript 6.1 Alternatimg Current & Power PPT

6.1 Alternating current and power
AC is used for power distribution because the peak voltage can be easily
changed using transformers
AC measurements
Frequency: f (Hz)
Peak
value
* An AC repeatedly reverses its direction
* In one cycle the charge carriers move in
one direction then the other.
* Mains frequency is 50 Hz ,
one cycle lasts 1/50 sec
= 0.02 sec = time period T
f = 1
T
Peak to peak
value
6.1 Alternating current and power
AC is used for power distribution because the peak voltage can be easily
changed using transformers
AC measurements
Frequency: f (Hz)
Peak
value
* An AC repeatedly reverses its direction
* In one cycle the charge carriers move in
one direction then the other.
* Mains frequency is 50 Hz ,
one cycle lasts 1/50 sec
= 0.02 sec = time period T
f = 1
T
Peak to peak
value
6.1 Alternating current and power
AC is used for power distribution because the peak voltage can be easily
changed using transformers
AC measurements
Frequency: f (Hz)
Peak
value
* An AC repeatedly reverses its direction
* In one cycle the charge carriers move in
one direction then the other.
* Mains frequency is 50 Hz ,
Peak to peak
value
6.1 Alternating current and power
AC is used for power distribution because the peak voltage can be easily
changed using transformers
AC measurements
Frequency: f (Hz)
* An AC repeatedly reverses its direction
* In one cycle the charge carriers move in
one direction then the other.
* Mains frequency is 50 Hz ,
6.1 Alternating current and power
AC is used for power distribution because the peak voltage can be easily
changed using transformers
AC measurements
Frequency: f (Hz)
Peak
value
* An AC repeatedly reverses its direction
* In one cycle the charge carriers move in
one direction then the other.
* Mains frequency is 50 Hz ,
6.1 Alternating current and power
AC is used for power distribution because the peak voltage can be easily
changed using transformers
AC measurements
Frequency: f (Hz)
Peak
value
* An AC repeatedly reverses its direction
* In one cycle the charge carriers move in
one direction then the other.
* Mains frequency is 50 Hz ,
Peak to peak
value
6.1 Alternating current and power
* Mains frequency is 50 Hz ,
one cycle lasts 1/50 sec
= 0.02 sec = time period T
One cycle
f = 1
T
Peak
value
Peak to peak
value
6.1 Alternating current and power
The heating effect of an alternating current:
varies according to the square of the current
P = I V = I2R
R = resistance of heater
maximum power is supplied = Io2 R
At peak current
Io
At zero current
zero power is supplied
Equal areas above and below mean value
Mean power supplied =
½ Io 2 R
also Av value of a sin 2 plot = 1/2
6.1 Alternating current and power
The heating effect of an alternating current:
varies according to the square of the current
P = I V = I2R
R = resistance of heater
maximum power is supplied = Io2 R
At peak current
Io
At zero current
zero power is supplied
Equal areas above and below mean value
Mean power supplied =
½ Io 2 R
also Av value of a sin 2 plot = 1/2
6.1 Alternating current and power
The heating effect of an alternating current:
varies according to the square of the current
P = I V = I2R
R = resistance of heater
maximum power is supplied = Io2 R
At peak current
Io
At zero current
zero power is supplied
Equal areas above and below mean value
Mean power supplied =
½ Io 2 R
also Av value of a sin 2 plot = 1/2
6.1 Alternating current and power
The heating effect of an alternating current:
varies according to the square of the current
P = I V = I2R
R = resistance of heater
maximum power is supplied = Io2 R
At peak current
Io
At zero current
zero power is supplied
Equal areas above and below mean value
Mean power supplied =
½ Io 2 R
also Av value of a sin 2 plot = 1/2
6.1 Alternating current and power
The heating effect of an alternating current:
varies according to the square of the current
P = I V = I2R
maximum power is supplied = Io2 R
At peak current
Io
At zero current
zero power is supplied
Equal areas above and below mean value
Mean power supplied =
½ Io 2 R
R = resistance of heater
6.1 Alternating current and power
The heating effect of an alternating current:
varies according to the square of the current
P = I V = I2R
R = resistance of heater
maximum power is supplied = Io2 R
At peak current
Io
At zero current
zero power is supplied
Equal areas above and below mean value
Mean power supplied =
½ Io 2 R
also Av value of a sin 2 plot = 1/2
6.1 Alternating current and power
6.1 Alternating current and power
6.1 Alternating current and power
6.1 Alternating current and power
6.1 Alternating current and power
6.1 Alternating current and power
6.1 Alternating current and power
The mean power supplied to a resistor:
6.1 Alternating current and power
The mean power supplied to a resistor:
6.1 Alternating current and power
6.1 Alternating current and power