Beee PPT - 3
Beee PPT - 3
Beee PPT - 3
Ohms law
Kirchhoff’s laws (KCL, KVL)
Series and parallel circuits
Source transformations
Mesh, super mesh analysis
Nodal, super node analysis.
Linearity and superposition theorem with simple examples
Thevenin's theorem
Norton's theorem with simple examples
Maximum power transfer theorem with simple examples.
Delta-wye conversion
• Kirchoff Voltage
KVL Law
• Kirchoff Current
KCL Law
Kirchoff’s Voltage Law (KVL) states that the
algebraic sum of the voltages across any set
of branches in a closed loop is zero. i.e.;
Vacrossbranches = 0
Below is a single loop circuit. The KVL computation is
expressed graphically in that voltages around a loop are
summed up by traversing (figuratively walking around) the
loop. Part of Traversal
+ Vr1 -
R1
10V + Assumed
current R2 + Vr2 -
- direction
R3
+ Vr3 -
R1
R1
10V + R2 + Vr2 - +
- 10V
-
R2 + Vr2 -
R3
R3
+ Vr3 -
+ Vr3 -
For both summations, the assumed current direction was the same
Assuming the current direction fixes the voltage references
+ Vr1 - + Vr1 -
R1 R1
Assumed Assumed
10V + current R2 + Vr2 - 10V + current R2 + Vr2 -
- direction - direction
R3 R3
+ Vr3 - + Vr3 -
For both cases shown, the direction of summation was the same
Example
Resistors of R1= 10Ω, R2 = 4Ω and R3 = 8Ω are
connected up to two batteries (of negligible
resistance) as shown. Find the current through each
resistor.
Continuing
Closed loops
Capacitors
None
Nodal Analysis applies the following principles…
Mesh Analysis is easiest when a circuit has more than two nodes
Three
Four
Five
Six
How much is current I3 in the node shown?
2A
-2A
0A
8A
How much is current I4 in the node shown?
2A
-2A
18A
8A
How much is voltage V3 in the closed loop circuit
shown?
2A
-2A
10A
-10A
How much is voltage V4 in the closed loop circuit
shown?
4A
-4A
8A
-8A
Using KVL, find the value of Rx in the circuit
shown
8Ω
4Ω
2Ω
1Ω
Q
Q2 1
Q3 Q4
Q5 Q6
Q7 Q8
Q9 Q10
Q1
Q2
Q3 Q4
Q5 Q6
Q7 Q8
Q9 Q10