Upload
defjedi
View
221
Download
0
Embed Size (px)
Citation preview
8/13/2019 6- R-L series cct
1/30
09/01/2014 1
AC R-L Series
Circuits
8/13/2019 6- R-L series cct
2/30
09/01/2014 2
Revision Of AC Pure R
Circuit
R
V R
I
V R I
8/13/2019 6- R-L series cct
3/30
09/01/2014 3
Revision Of AC Pure L
CircuitI
V L
V L
I
V L
I
OR
8/13/2019 6- R-L series cct
4/30
09/01/2014 4
AC R-L Series Circuit
V
R I
V R V L
V L
I
V R
8/13/2019 6- R-L series cct
5/30
09/01/2014 5
AC R-L Series Circuit
V L
I V R
V
I
V
V R
V
VL
8/13/2019 6- R-L series cct
6/30
09/01/2014 6
Characteristics Of AC
R-L Series CircuitI is in phase with V R
VR = IRI lags V L by 90 0
VL = IXL I lags V by
V L
I V R
V
8/13/2019 6- R-L series cct
7/30
09/01/2014 7
Opposition To Flow Of
Current In DC Circuit
Opposition to flow of current in DCcircuit is given by RR = V / I (ohm)
R
V
I
+ -
8/13/2019 6- R-L series cct
8/30
09/01/2014 8
Opposition To Flow Of
Current In AC Circuit
Opposition to flow of current in ACcircuit is given by Z Z = V / I (ohm)
Z
V
I
8/13/2019 6- R-L series cct
9/30
09/01/2014 9
Impedance (Z)
• Is the opposition to the flow of
current in an ac circuit.
• Is given by the ratio of V to I
i.e. Z = V / I ohm
8/13/2019 6- R-L series cct
10/30
09/01/2014 10
Impedance (Z)
V2 = V R2 + V L2 = (IR) 2 + (IX L)2 = (I2R2) + (I 2XL2)= I2(R 2 +XL2)
V2 / I2 = (R 2 +XL2)
V / I = (R 2 +XL2)
V R
V
V L
8/13/2019 6- R-L series cct
11/30
09/01/2014 11
Summary Of Impedance
Of AC R-L Series CircuitImpedance Z is the oppositionto the flow of current in an accircuit.Z is given by the ratio of V to Ii.e. Z = V / I
Also, Z = (R 2 +XL2)Unit of impedance is ohm
8/13/2019 6- R-L series cct
12/30
09/01/2014 12
Power Factor Of AC R-L
Series Circuit
Phase angle = I lags V by angle Therefore pf is lagging .
I
V
8/13/2019 6- R-L series cct
13/30
09/01/2014 13
Impedance Triangle
V R
V
V L
(i)I R
I Z
I X
L
(ii)
R
Z
X L
(iii) Impedance
Triangle
8/13/2019 6- R-L series cct
14/30
09/01/2014 14
Impedance Triangle
cos = R / Z
R = Z cos Z = R / cos
R
Z
X L
8/13/2019 6- R-L series cct
15/30
09/01/2014 15
Impedance Triangle
sin = XL / Z XL = Z sin Z = XL / sin
R
Z
X L
8/13/2019 6- R-L series cct
16/30
09/01/2014 16
Impedance Triangle
tan = XL / R XL = R tan R = XL / tan
R
Z
X L
8/13/2019 6- R-L series cct
17/30
09/01/2014 17
Summary Of AC R-L
Series Circuit
V
R
I
V R V L
V R
V
V L
I
VR = IR
VL = IX LV = IZI = V / Z
8/13/2019 6- R-L series cct
18/30
09/01/2014 18
Summary Of AC R-L
Series Circuit Z = V / I
Also, Z = (R2
+ X L2
) R = (Z 2 - XL2) XL = (Z 2 - R L2)
8/13/2019 6- R-L series cct
19/30
09/01/2014 19
Summary Of AC R-L
Series Circuit
I lags V by angle pf is lagging
I
V
8/13/2019 6- R-L series cct
20/30
09/01/2014 20
The End
hank You
8/13/2019 6- R-L series cct
21/30
09/01/2014 21
AC R-L Series Circuit
Z = V / I Z = (R 2 + X L2)
V = IZVR = IR
VL = IXL
8/13/2019 6- R-L series cct
22/30
09/01/2014 22
Impedance Triangle (RL)
R
XL
COS = R / Z
8/13/2019 6- R-L series cct
23/30
8/13/2019 6- R-L series cct
24/30
09/01/2014 24
AC RC-Series Circuit
Z = V / I Z = (R 2 + X c 2)
V = IZVR = IR
Vc = IX cI leads V by angle Therefore pf is leading
8/13/2019 6- R-L series cct
25/30
09/01/2014 25
Impedance Triangle (RC)
R
XCZ
COS = R / Z
8/13/2019 6- R-L series cct
26/30
09/01/2014 26
AC RLC Series Circuit
Z = V / I Z = [R 2 + (X L - Xc) 2]
V = IZVR = IRVL = IXL
Vc = IX cI leads V by angle Therefore pf is leading
8/13/2019 6- R-L series cct
27/30
09/01/2014 27
AC RLC Series Circuit
If XL > Xc I lags V by angle
Therefore pf is leading
If XL < Xc
I leads V by angle Therefore pf is leading
8/13/2019 6- R-L series cct
28/30
09/01/2014 28
AC RLC Series Circuit
If XL = Xc V = V R
I is in phase with V pf = 1 Z = R
Therefore Z = minimum valueTherefore I = maximum valueI = V / R
8/13/2019 6- R-L series cct
29/30
09/01/2014 29
AC Series Resonance
CircuitIs a circuit where X L = Xc Current is in phase with voltage
pf = 1Z = minimum valueI = maximum value
I = V/R
8/13/2019 6- R-L series cct
30/30
09/01/2014 30
Summary Of Formulae
For AC Series CircuitV = IZI = V / Z
Z = V /IZ = (R 2 + X 2)
• COS = R / Z