Civil Engineering Reference
In-Depth Information
nodes
and
We obtain
This implies that for a conductance connected between nodes and there
are no contributions to the matrix, and the LHS matrix has only four
entries: at the and positions, and at the and
positions. It may be observed that since a conductance is a Type 1 element,
the only contributions are to the
RHS
region of the MNA matrix.
Constant current sources.
Now consider another Type 1 element: a con-
stant current source
on a branch
directed from node
to node
Its
contribution to the KCL equation is
Substituting the device equation for the conductance,
we can find its
stamp as
The stamp for a constant current source is, therefore, an entry of
in the
RHS matrix in the
position and
in the
position.
Constant voltage sources.
A constant voltage source of value
V
connected
on a branch between nodes and is an example of a Type 2 element.
Therefore, its contributions to the KCL equation are similar to the elements
above; the difference here is that the branch current variable remains present
in the final set of MNA equations.
The Type 2 device equation, combined with the KVL equation, states that
This is written in the lower part of the MNA matrix, after all
