Transcript Node - Voltage Method ECE 201 Circuit Theory I 1

Node - Voltage Method
ECE 201 Circuit Theory I
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Identify the nodes.
There are 3 “essential” nodes.
Node 0 is the “ground” or “reference” node where
the voltage is equal to zero.
Therefore there will be 2, or (ne – 1) node-voltage
equations.
ECE 201 Circuit Theory I
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• Identify the node voltages
– The node voltage is the voltage rise from the reference
node (0) to a non-reference node (1 or 2).
• Label the voltages as v1 and v2.
ECE 201 Circuit Theory I
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Write KCL at each non-reference node.
Consider the current to be positive if it is leaving
the node.
Accept the given directions of any current
sources.
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Node1
v  10 v v  v
 
0
1
5
2
1
1
1
2
Node2
v v v

20
2
10
2
1
2
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Solving for the voltages yields,
V1 = 9.09 volts
V2 = 10.91 volts
With polarities as assigned
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