Ch03-Slides-#02Thursday, February 2, 2017 7:26 PM

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A supernode is the combination of two extraordinary nodes (excluding the

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A supernode is the combination of two extraordinary nodes (excluding the reference node) between which a voltage source exists. The voltage source may be of the independent or dependent type, and the voltage source may include elements in parallel with it (such as a resistor) but not in series with it. If one of the two nodes of a supernode is a reference (ground) node, it is called a quasi-supernode.

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Supernode Attributes

(1) At a supernode, Kirchhoff's current law (KCL) can be applied to the combination of the two nodes as if they are a single node, but the two nodes retain their own identities.

(2) Kirchhoff's voltage law (KVL) is used to express the voltage difference between the two nodes in terms of the voltage of the source between them.

(3) If a supernode contains a resistor in parallel with the voltage source, the resistor will exercise no influence on the currents and voltages in the other parts of the circuit, and therefore, it may be ignored altogether.

(4) For a quisi-supernode, the node-voltage of the non-reference node is equal to the voltage magnitude of the source.

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Example 3-1: Circuit with Two Sources. For the circuit in Fig. 3-1, (a) identify all extraordinary nodes and select one of them as the ground node, (b) develop node-voltage equations at the remaining extraordinary nodes, (c) solve for the node voltages, and then (d) calculate the power consumed by R5. The

element values are V0 = 10 V, I0 = 0.8 A, R1 = 5 Ω, R2 = 2 Ω, R3

= 3 Ω, R4 = 10 Ω, and R5 = 2.5 Ω.

Ch03-Examples #01Wednesday, February 8, 2017 11:17 AM

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Example 3-2: Dependent Current Source. The circuit of Fig. 3-2 contains a current-controlled current source (CCCS) whose magnitude Ix is governed by the current

flowing through the 6-Ω resistor I nthe direction shown. Determine Ix.

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Quiz #04Friday, February 10, 2017 10:32 AM

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Quiz #04 SolutionFriday, February 10, 2017 10:45 AM

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