Here is an approach called the Z-bus approach which is a generalized
Thevenin method used for fault analysis of power grids.
Take node 3 as a reference and write a nodal admittance matrix
In this case node 0 ties to nodes 1 and 2 but not to the reference node 3
In the matrix we have at node 0 the sum of the admittances (1/R) to each
node connected to it. and the off diagonal admittances are - the branch
admittances
row 0 is then 2 _1 _1 (0 is connected to 1 and 2)
row 1 is then _1 2 0 ( node 1 is connected to 0 and reference but not
to 2)
row 2 is _1 0 2 node 2 is connected to 0 and reference but not to 1
so we get
y=:>2 _1 _1;_1 2 0; _1 0 2
y
1 _1 0
_1 3 _1
0 _1 2
Now invert:
%.y
1 0.5 0.5
0.5 0.75 0.25
0.5 0.25 0.75
Since 3 is the reference the resistance from 1 to 3 is the diagonal value
(<0;0){z
1
The resistance from 1 to 3 and from 2 to 3 is 0.75
This can be extended to large networks and in such cases, the Z bus
matrix is built piece by piece avoiding inversion of a large matrix.
Don
On 08/01/2013 8:11 AM, Raul Miller wrote:
On Mon, Jan 7, 2013 at 9:54 PM, Don & Cathy Kelly <[email protected]> wrote:
There is a way to deal with this using the Zbus matrix but, in this case it
would be use of a pile driver where a tack hammer works.
I might want the pile driver? I am not looking for an algorithm
optimized for this particular argument.
But I should go study the rosettacode page.
Thanks,
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